3412 (PEEC) INDUSTRIAL ENGINE ELECTRONIC TROUBLESHOOTING Caterpillar

These tests are designed to establish whether a component and related parts are working properly, and if not, to pinpoint the faulty component.

These tests may also be used for basic health checks, to determine if problems exist, or as a guide to check for intermittent problems.

P-201: Inspecting Electrical Connectors

Many of the Operational Procedures and Diagnostic Code Procedures in this troubleshooting guide will direct you to check a specific electrical connector. Use the following steps to help determine if the connector is the cause of the problem. If a problem is found in the electrical connector, repair the connector and continue the test procedure.

1. Check connector lock ring.

Make sure that connector was properly locked and that the lock ring is capable of locking connector together.

2. Perform 10 pound pull test on each pin/wire.

Each pin and connector should easily withstand 10 pounds of pull, and remain in the connector body. This test checks whether the wire was properly crimped in the pin, and whether the pin was properly inserted into the connector. Repair as needed.

NOTE: Any time a wire is removed from a connector for testing purposes, do a 10 pound pull test after reinserting the wire.

NOTE: Pins should ALWAYS be crimped onto the wires; NEVER soldered. Use 1U5804 Crimping Tool (part of 4C3406 Connector Repair Kit).

3. Visually inspect wiring.

Look for worn or abraded wires. Check for pinched or damaged harnesses.

4. Visually inspect connectors.

Verify that pins and sockets are not corroded or damaged. Verify proper alignment and location of pins in the connector.

5. Check individual pins and sockets.

This is especially important for intermittent problems. Using a new pin, insert the pin into each socket one at a time to check for a good grip on the pin by the socket. Repeat for each pin on the mating side of the connector, using a new socket for the test.

P-210: Electrical Power Supply To PEEC Test

The PEEC ECM receives + 12 volt DC power from the 24/12 volt DC power converter (Pin 1), through the Electronic Speed Switch (ESS) (Pin 8 in, Pin 9 out), to J2/P2 pin A (+ battery).

Throughout these test procedures, when "battery voltage" is mentioned, it refers to the 12 volts DC (+ Battery) that is supplied to PEEC from the 24/12 volt converter. Ground (- Battery) comes from the terminal board (Pin 32) to the System Connector (J2/P2) Pin B.

In typical applications, PEEC receives power whenever the Master Power Switch is turned ON.

Keep in mind that these devices may be the cause of no (or intermittent) power to the ECM.

This procedure tests whether proper voltage is being supplied to the ECM.

Note that the ECAP is supplied with electrical power through direct connections inside the ECM. Therefore, if the ECAP has power, so does the ECM.

For intermittent problems that could be caused by system wiring (such as intermittent shutdowns), temporarily bypassing the system wiring may be an effective means of determining the root cause. If symptoms vanish with the wiring bypassed, system wiring was the cause. A means of bypassing system wiring is explained below.

Step 1. Check Electrical Connectors And Wiring

Check system connector (J2/P2) and + 12 volt power and grounds to J2/P2, being sure to:

* Check Connector lock rings.

* Perform 10 pound pull test on each pin or wire.

* Inspect wiring for damage or abrasion.

* Inspect connectors for damage or corrosion. Refer to P-201: Inspecting Electrical Connectors for details. Repair any damage, then continue with the next step.

* Visually and physically check grounds for looseness or corrosion. If a problem is found, disconnect, clean, and reconnect the connector

Step 2. Check Battery Voltage Coming To ECM

A. Connect a 9-pin "T" at the ECM system connector (J2/P2).

B. Turn power switch(es) ON, engine OFF.

C. Measure the voltage between + Battery (Pin A) and ground (Pin B).

The voltage at Pin A should be between 11.5 and 13.5 VDC.

OK: The ECM is currently receiving the correct voltage. If intermittent problems with battery voltage may be occurring, consider temporarily bypassing system wiring as shown in Step 4. Otherwise, Stop.

NOT OK: The ECM is NOT receiving the correct voltages. Continue with the next step.

Step 3. Check Batteries

A. Measure battery voltage at the battery posts.

B. Load test the batteries using the 4C4911 Battery Load Tester. Make reference to Operation Manual, Form No. SEHS9249 for more complete information for use of the 4C4911 Battery Load Tester.

The voltage at the batteries should be at least 11.5 VDC, and the batteries should pass the load test.

OK: The batteries are not the problem. Wiring or components between the batteries and PEEC are preventing voltage from reaching PEEC.

NOT OK: The batteries are defective. Replace the defective batteries. Stop.

Step 4. Bypass System Wiring For Testing

NOTE: This bypass is for TEST PURPOSES ONLY. It may be left on the system temporarily to test whether intermittent problems are due to interruptions in battery power to the ECM. The bypass switch is installed in parallel with the power switch. Either one will turn power ON, and both must be OFF to turn power OFF and shutdown the engine.

Use a spare 12 volt battery for test purposes, or a 120 volt AC to 12 volt DC power converter capable of supplying at least 7.5 amps at 12 volts, filtered.

A. Build a bypass circuit as shown in the illustration below, using #14 AWG wire.

System Power Bypass Circuit - for TEST PURPOSES ONLY

B. Connect the battery end of the bypass DIRECTLY to the battery posts (or power converter).

C. Remove Pins A (+ Battery) and B (-Battery) from J2 (System connector - system side).

D. Insert the other end of the bypass into J2 Pins A and B (as shown below).

E. Connect the wire that was formerly in J2 Pin B into the socket spliced into the bypass.

F. Connect the wire that was formerly in J2 Pin A into the socket that is spliced into the bypass. (This supplies power to the throttle sensor and through the bypass rather than the system wiring). Tape this connection to keep it clean, prevent shorting, and prevent loosening during operation. Then turn the master power switch OFF. This will isolate the PEEC system from the original system power circuit.

G. Install the temporary switch on the front panel.

H. After tests are complete, restore all wiring to original condition.

The engine should perform normally with the bypass installed.

OK: If symptoms disappear with the bypass installed, but come back when it is removed, the problem is in the system wiring supplying power to PEEC. Repair as needed. Stop.

NOT OK: If symptoms continue even with the bypass installed, the problem is in PEEC. Continue with the procedure in this manual that best describes the symptom(s).

P-211: Throttle Control Sensor Test

The Throttle Control Sensor (TCS) is used to provide a throttle signal to the ECM. Sensor output is a constant frequency signal whose pulse width varies with throttle setting. This output signal is referred to as either "Duty Cycle" or a "Pulse Width Modulated (PWM)" signal and is expressed as a percentage. When correctly adjusted, the TPS will produce a "Duty Cycle" of 15 to 20% at low idle and 80 to 85% at full throttle. The throttle position sensor will produce a "Duty Cycle" signal of 10 to 22% at low idle and 75 to 90% at full throttle. This is then translated by the ECM into a "Throttle Position" of 3 to 100%.

The 3412 (PEEC) Industrial Engine does not use either of the rotary type Throttle Position Sensors found on 3406B PEEC on-highway truck applications. Instead, the Throttle Control Sensor converts the electrical signal from a PC to a Duty Cycle (PWM) signal, which is then sent to the engine control logic in the ECM.

The ECM translates the input Duty Cycle signal into Throttle Position ("Throttle Pos" on the ECAP Display Status Screen).

Step 1. Check Electrical Connectors And Wiring

Check the system connector (J2/P2) and throttle control connector (J12/P12) and wiring between them, being sure to:

* Check Connector lock rings.

* Perform 10 pound pull test on each pin or wire.

* Inspect wiring for damage or abrasion.

* Inspect connectors for damage or corrosion. Refer to P-201: Inspecting Electrical Connectors for details. Repair any damage, then continue with the next step.

Step 2. Check Throttle Position Reading

A. Turn power switch(es) OFF, then back ON to reset the throttle position reading.

B. Observe the "Throttle Pos" reading on the "Display Status" screen of the ECAP while varying the input signal from the PC.

The "Throttle Pos" should read 3% at the minimum setting and progressively increase to 100% when the throttle is at the maximum setting.

OK: The throttle control sensor is currently operating correctly. Stop.

NOT OK: Continue to next step.

Step 3. Check Throttle Control Sensor Voltage Supply

A. Install a 5-pin "T" at throttle sensor connector (J12/P12).

B. Measure the voltage between + Battery (Pin A) and ground (Pin B) on the "T".

The supply voltage to the sensor should be between 11.5 and 13.5 VDC

OK: Voltage supply OK. Continue to next step.

NOT OK: The throttle position sensor is not being supplied with the correct voltage. Inspect the system wiring, 24/12 VDC converter and circuit breaker CB2 for a problem. Stop.

Step 4. Check Throttle Control Sensor Output Duty Cycle At Throttle Sensor

A. Remove throttle sensor wire (Pin C) from J12. (This disconnects system wiring from the sensor).

B. Connect the ECAP's PWM probe to Pin C of the "T".

C. Use the ECAP to display the Duty Cycle output of the throttle sensor while varying the input signal from the PC.

The DUTY CYCLE should be between 15 and 20% at the minimum setting and increase to between 80 and 85% at the maximum setting.

D. Reinsert Wire C in J12.

OK: The throttle control sensor is OK. Continue to next step.

NOT OK: The throttle control sensor is defective. Replace the sensor. Stop.

Step 5. Check Throttle Control Sensor Duty Cycle At ECM

A. Remove throttle signal (Wire E) from P2. (This disconnects the ECM from the throttle signal).

B. Install a 9-pin "T" at system connector (J2/P2).

C. Connect the PWM probe to Pin E on the "T".

D. Use the ECAP to display the Duty Cycle of the throttle control sensor while varying the input signal from the PC.

The DUTY CYCLE should be between 15 and 20% at the minimum setting and increase to between 80 and 85% at the maximum setting.

E. Reinsert Wire E in P2.

OK: A good throttle signal is reaching the ECM. Continue to next step.

NOT OK: The harness is damaged between the ECM and the throttle control sensor. Inspect and repair as necessary. Stop.

Step 6. Check ECM

A. Be sure that the wires removed in Steps 4 and 5 have been reinserted.

B. Check to see if Diagnostic Code 32 is ACTIVE.

OK: NOT ACTIVE: The throttle sensor and ECM are currently operating correctly. Stop.

NOT OK: ACTIVE: The ECM is not reading the throttle sensor signal. Be sure that it was determined in Step 5 that a good throttle signal is reaching the ECM and verify that the ECM is receiving proper voltage from the battery. If so, replace the ECM. Stop.

P-212: Diagnostic Lamp Test

The Diagnostic Lamp is used to indicate the existence of a fault and may be used to read Diagnostic Codes. While the engine is operating, it will go on for a minimum of five seconds any time a fault condition exists. It will remain on as long as the fault is ACTIVE.

On power up and on engine start up, the lamp comes ON for five seconds, blinks OFF, comes ON for another five seconds, then goes OUT for five seconds. After this time, ACTIVE diagnostic codes will be flashed out.

One terminal of the lamp is supplied with +24 volts whenever the master power switch is ON. The other terminal is connected to the ECM at P1/J1 Pin G to turn the lamp on. Pin G will be at +24 volts DC when the lamp is OFF, and less than two volts when the lamp is turned ON.

Step 1. Test Lamp Through ECM

Turn master power switch ON, engine OFF.

The lamp should come ON for ten seconds, then OUT for five seconds, then flash diagnostic codes.

OK: Lamp is working normally. Stop.

NOT OK: Lamp is not working properly. Continue to next step.

Step 2. Bypass The ECM

A. Remove diagnostic lamp wire from P1, Pin G, and ground the wire.

B. Turn master power switch ON, engine OFF. Lamp should come ON and stay ON.

OK: The lamp circuit is OK, but the ECM is not grounding the lamp. Replace the ECM. Stop.

NOT OK: Verify that power is reaching lamp socket. If so, replace bulb. Stop.

P-220: ECM/Personality Module Test

The Electronic Control Module (ECM) is the computer which controls a PEEC engine. The Personality Module is the software which controls how the computer behaves. The two must be used together - neither can do anything by itself.

The Personality Module consists of:

* All of the software, or instructions, for the ECM to do its job. Because of this, updating the Personality Module to a new version may cause the engine to behave in a different manner. The section on Summary Of PEEC Personality Module Changes in this manual describes the changes that have been made to the software.

* Performance Maps, which define fuel rate, timing, etc. for various operating conditions to achieve optimum performance while meeting emission requirements. These are programmed at the factory only.

* Logged Diagnostics. PEEC may log certain diagnostic codes into this memory so that a permanent record of the diagnostic is retained. Refer to the section Troubleshooting Diagnostic Codes, for further information on logged codes.

The ECM consists of:

* A microprocessor, to perform the computing necessary to perform the ECM's functions (governing, generating diagnostic codes, communicating with service tools, etc.). The microprocessor gets its instructions from the software in the Personality Module.

* Programmable Parameters stored in permanent memory (both Customer Specified and System Configuration Parameters). Refer to the section Programming PEEC Parameters for details on what these parameters do.

* Input Circuits, to filter electrical noise from sensor signals and to protect sensitive internal circuits from potentially damaging voltage spikes.

* Output Circuits, to provide the high currents necessary to turn on lamps or solenoids as the microprocessor chooses.

* Power circuits, to provide clean stable electrical power to internal circuits and external sensors.

NOTE: The 3412 PEEC utilizes mechanical timing advance.

Step 1. Inspect Electrical Connectors And Wiring

Inspect all wiring and connectors coming in and out of the ECM for damage, corrosion, or incorrect attachment. Repair any problems.

Step 2. Inspect The Personality Module Connector And Gasket.

A. Remove the Personality Module. Note gasket location and orientation while removing the module.

B. Inspect the connector on the Personality Module and on the ECM for corrosion or damage.

C. Inspect the gasket to be sure that it was properly aligned when installed. Also check that the cork shipping gasket was removed before previous assembly.

D. Re-install the module, or replace or repair as needed.

Step 3. Check Communication With ECAP

A. Install ECAP.

B. Read Customer Specified Parameters (see instructions for the service tool for details).

C. Read LOGGED Codes (if equipped with Personality Module built since May 1989).

D. Start the engine.

The ECAP should be able to read correct parameters, the hour meter for logged codes should represent approximate operating time for the Personality Module, and the engine should start and run normally.

OK: The Personality Module is OK. The microprocessor in the ECM is able to properly function and read the memory in the ECM and Personality Module. The remainder of the ECM (input circuits, output circuits, and sensor supply and reference voltage circuits) are to be tested individually. If operational problems persist, refer to the procedure in this manual best describing the symptoms. Stop.

NOT OK: * If the ECAP will not communicate with the ECM, refer to P-120: ECAP will Not Communicate With PEEC.

* If the Customer Specified Parameters are not as expected, reprogram the parameters. Completely scrambled parameters could mean the ECM is defective.

* If the hour meter for logged codes is scrambled or stuck at zero, or the logged codes are completely scrambled, the Personality Module may be defective. Excessive voltage spikes in the electrical system may also cause scrambled logged codes or hour meter reading. Locate the source of the electrical spike and suppress the spike with a diode across the relay or solenoid coil.

* If the engine will not start, refer to P-102: Engine Cranks But Will Not Start.

P-221: Sensor Supply Voltage Test

The PEEC ECM converts the battery voltage into 5V and 8V sensor supply voltages. These supply voltages are used to supply power and reference voltages to the following sensors: rack, engine speed, boost pressure and air inlet pressure (atmospheric) sensor (in transducer module), and oil pressure (in transducer module). In addition to using the sensor supply voltages for the boost air inlet, and oil pressure sensors, the transducer module has internal connections which pass the sensor supply voltages on to the rack sensor and engine speed sensor.

NOTE: A short anywhere on the 8 volt sensor supply circuit will cause loss of the engine speed signal, which will result in an engine shutdown.

Step 1. Check Electrical Connectors And Wiring

Check ECM/sensors (J3/P3) and transducer module (J5/P5), timing position sensor (J7/P7), rack position sensor (J8/P8), and engine speed sensor (J9/P9) connectors and wiring between them, being sure to:

* Check Connector lock rings.

* Perform 10 pound pull test on each pin or wire.

* Inspect wiring for damage or abrasion.

* Inspect connectors for damage or corrosion. Refer to P-201: Inspecting Electrical Connectors for details. Repair any damage, then continue with the next step.

Step 2. Check Supply Voltages At ECM

A. Connect a 9-pin "T" at J3 ONLY (sensors connector at ECM), leaving P3 and harness disconnected from "T".

B. Turn power switch(es) ON, engine OFF.

C. Measure the 8V sensor supply voltage [Pin H (+8V) to Pin B (ground analog)] and the 5V reference voltage [Pin C (+5V ref.) to Pin B].

The 8V sensor supply voltage should be 8.0 ± 0.4 VDC and the 5V reference voltage should be 5 ± 0.25 VDC.

OK: The ECM is supplying the correct voltages. Continue to next step.

NOT OK: The ECM is NOT supplying the correct voltages. Refer to P-210: Electrical Power Supply To PEEC test to verify that the ECM is getting battery voltage. If it is, replace the ECM. Stop.

Step 3. Check For Components Shorting Supply Voltages

A. Connect the 9-pin "T" to both J3 AND P3 (sensors connector at ECM).

B. Turn power switch(es) ON, engine OFF.

C. Measure the 8V sensor supply voltage (Pin H to Pin B) and the 5V reference voltage (Pin C to Pin B).

The 8V sensor supply voltage should be 8.0 ± 0.4 VDC and the 5V reference voltage should be 5 ± 0.25 VDC.

OK: There are no components shorting the supply or reference voltages. Continue to next Step 4.

NOT OK: A PEEC component is shorting either the 8V sensor supply voltage or the 5V reference voltage. Disconnect the transducer module, rack position sensor, engine speed sensor and engine harness one at a time while monitoring the 8V sensor supply and 5V reference voltages to determine which component is causing the short, and replace or repair that component.

If one of the voltages drops no matter which component is connected, the voltage supplies in the ECM may not be able to supply enough current. If so, replace the ECM. Stop.

Step 4. Check Supply Voltages To Transducer Module

A. Connect a 9-pin "T" at transducer module connector (J5/P5).

B. Measure the 8V sensor supply voltage (Pin H to Pin B) and the 5V reference voltage (Pin C to Pin B).

The 8V sensor supply voltage should be 8.0 ± 0.4 VDC and the 5V reference voltage should be 5 ± 0.25 VDC.

OK: Supply voltages are OK to transducer. Continue to next step.

NOT OK: Inspect connectors and wiring between ECM and transducer for damage or a broken connection. Repair any problems. Stop.

Step 5. Check Supply Voltages To Rack Position Sensor

A. Connect a 5-pin "T" at rack sensor connector (J8/P8).

C. Measure the 8V sensor supply voltage (Pin A) and 5V reference voltage (Pin C) with respect to ground (Pin B).

The 8V sensor supply voltage (Pin A) should be 8.0 ± 0.4 VDC and the 5V reference voltage (Pin C) should be 5 ± 0.25 VDC.

OK: Supply voltages are OK to the rack sensor. Continue to next step.

NOT OK: Supply voltages are making it to the transducer, but not through it. Replace the transducer. Stop.

Step 6. Check Supply Voltages To Engine Speed Sensor

A. Connect a 3-pin "T" at engine speed sensor connector (J9/P9).

B. Measure the 8V sensor supply voltage (Pin A to Pin B).

The 8V sensor supply voltage should be 8.0 ± 0.4 VDC.

OK: Supply voltages are OK to all PEEC components. Stop.

NOT OK: Supply voltages are making it to the transducer, but not through it. Replace the transducer module. Stop.

P-222: Engine Speed Signal Test

The PEEC engine speed sensor determines engine speed by magnetically detecting the movement of teeth on the fuel pump camshaft retainer. PEEC will not try to start the engine (either energize the shutoff solenoid or move the BTM) until it senses an engine speed signal. Engine speed is determined by the FREQUENCY, not the voltage, of the engine speed sensor output. The output frequency should be between 0 and 460 Hz. The sensor is supplied with 8V from the ECM through the transducer module.

Step 1. Inspect Electrical Connectors And Wiring

A. Check ECM/sensors (J3/P3) and transducer module (J5/P5) connectors and wiring between them, being sure to:

* Check Connector lock rings.

* Perform 10 pound pull test on each pin or wire.

* Inspect wiring for damage or abrasion.

* Inspect connectors for damage or corrosion. Refer to P-201: Inspecting Electrical Connectors for details. Repair any damage, then continue with the next step.

B. Remove the rear cover from the governor.

C. Inspect engine speed sensor (J9/P9) and wiring for abrasion, damage, or incorrect attachment. Repair any damage.

D. Remove engine speed sensor, and check sensing end of sensor for damage. Replace sensor if damaged.

E. Reinstall the components removed in the previous steps.

Step 2. Engine Speed Signal Operational Test

Start the engine.

The engine should start and run smoothly.

OK: The engine speed signal is currently operating correctly. Stop.

NOT OK: * Will Not Start: Refer to procedure P-102: Engine Cranks But Will Not Start. If the problem is still not found, continue to Step 3.

* Erratic RPM: Refer to procedure P-104: Erratic Or Unstable Engine RPM. If the problem is still not found, continue to Step 3.

Step 3. Check Engine RPM Reading On ECAP

Crank the engine while observing the "Engine RPM" reading on the "Display Status" screen of the ECAP.

"Engine RPM" while cranking should show a steady reading between 100 and 500 rpm.

OK: The engine speed sensor is currently working correctly. Stop.

NOT OK: The ECM is not reading an engine speed signal. Continue to next step.

Step 4. Check Engine Speed Signal At ECM

A. Connect a 9-pin "T" at the ECM/sensors connector (J3/P3).

B. Connect the PWM probe at Pin A (engine speed) of the "T".

C. Remove engine speed signal wire from ECM (Pin A of J3).

D. Crank the engine and observe the frequency of the engine speed sensor signal. Refer to the instructions included with the PWM probe (use the "Utility" function from the Main Menu, then select "PWM Sensor").

E. Reinsert Wire A in J3.

The Frequency displayed on the ECAP should be between 10 and 50 Hz and steady while cranking.

OK: The engine speed signal is reaching the ECM. If Step 3 showed that the ECM was not reading the signal, the ECM is faulty. Replace the ECM. Stop.

NOT OK: The engine speed signal is not reaching the ECM. Continue to next step.

Step 5. Check Engine Speed Signal Through Transducer Module

A. Connect a 9-pin "T" at the transducer module connector (J5/P5).

B. Remove engine speed signal wire from the engine harness (Pin A of J5).

C. Connect the PWM probe to Pin A (engine speed) of the "T".

D. Crank the engine and observe the frequency of the engine speed sensor output. Refer to the instructions included with the PWM probe (use the utility function from the main menu, then select "PWM sensor").

E. Reinsert Wire A in J5.

The frequency displayed on the ECAP should be between 10 and 50 Hz and steady while cranking.

OK: The engine speed sensor is working, and its signal is getting through the transducer module but not reaching the ECM. Check connections and the wiring between the ECM and transducer for damage, corrosion, or incorrect attachment. Repair as needed. Stop.

NOT OK: Engine speed signal is not reaching the transducer module connector. Continue to the next step.

Step 6. Check Sensor Supply Voltage At Engine Speed Sensor

A. Connect a 3-pin "T" at engine speed sensor connector J9/P9.

B. Measure the 8V sensor supply voltage (Pin A to Pin B of the "T").

The voltage should be 8 ± 0.4 VDC.

OK: The engine speed sensor is receiving proper voltage. Continue to next step.

NOT OK: The engine speed sensor is not getting proper supply voltage. Refer to P-221: Sensor Supply Voltage Test. Stop.

Step 7. Check Engine Speed Sensor Operation

A. Connect the PWM probe at engine speed signal (Pin C) of the "T".

B. Remove engine speed signal wire from the transducer (Pin C of P9).

C. Crank the engine and observe the frequency of the engine speed signal. Refer to the instructions included with the PWM probe (use the "Utility" function from the main menu, then select "PWM Sensor").

E. Reinsert Wire C in P9.

The frequency displayed on the ECAP should be between 10 and 50 Hz and steady while cranking.

OK: The engine speed sensor is OK, but the signal is not getting through the transducer module. Check for damaged wires or connectors coming from the transducer. If no damage is found, replace the transducer module. Stop.

NOT OK: The engine speed sensor is not generating a proper signal. Replace the sensor. Stop.

P-223: Shutoff Solenoid Test

Although the Rack Solenoid (BTM) is capable of shutting the engine down, the shutoff solenoid provides a redundant means for PEEC to shut down the engine. When the solenoid receives a voltage, the solenoid's plunger is pulled in to allow the engine to run. When the solenoid does not receive voltage, the plunger will release and the engine will not run.

Step 1. Check Electrical Connectors And Wiring

Check shutoff solenoid connector (J11/P11) and ECM/solenoids connector (J4/P4) and wiring between them, being sure to:

* Check Connector lock rings.

* Perform 10 pound pull test on each pin or wire.

* Inspect wiring for damage or abrasion.

* Inspect connectors for damage or corrosion. Refer to P-201: Inspecting Electrical Connectors for details. Repair any damage, then continue with the next step.

Step 2. Override Shutoff Solenoid Operation

A. Rotate the manual shutoff lever in the clockwise direction (CW) to override the shutoff solenoid.

B. Start the engine.

C. Release the manual shutoff lever.

The engine should have started, and should continue to run after the manual shutoff lever is released.

OK: The shutoff solenoid appears to be working. Continue to next step.

NOT OK: * If the engine will still not start, the problem is NOT with the shutoff solenoid. Refer to P-102: Engine Cranks But Will Not Start. Stop.

* If the engine starts but dies when manual lever is released, the shutoff solenoid is not working. Proceed to Step 5.

Step 3. Verify That Shutoff Solenoid Can Shutdown Engine

A. Start engine.

B. Disconnect shutoff solenoid connector (J11/P11).

The engine should shutdown when the shutoff solenoid is disconnected.

OK: Shutoff solenoid is able to shutdown engine. Continue to next step.

NOT OK: Shutoff solenoid IS NOT able to shutdown engine. Check for sticking solenoid plunger or linkage. Then repeat this step.

Step 4. Measure Operating Voltage At Shutoff Solenoid

A. Connect a 3-pin "T" at shutoff solenoid connector (J11/P11).

B. Rotate the manual shutoff lever in a clockwise (CW) direction to override the shutoff solenoid.

C. Start the engine and allow it to warm up to operating temperature.

D. Measure the voltage between shutoff signal (Pin A) and ground (Pin B) of the "T" during cranking, and while the engine is running.

The voltage should jump to over 4 volts during cranking and then stabilize at between 1.5 and 2.5 volts DC.

OK: The shutoff solenoid is currently operating correctly. Stop.

NOT OK: The shutoff solenoid is not getting proper voltage.

* If voltage is less than 1.5 VDC, replace the shutoff solenoid and retest. If voltage is still too low, proceed to Step 6.

* If voltage is greater than 2.5 VDC, verify proper wiring of the crank line (refer to Step 2). If crank line is OK, proceed to Step 6.

Step 5. Check Resistance Of Solenoid Coil

A. Disconnect shutoff solenoid.

B. Measure the resistance across the solenoid coil (Pin A to Pin B of J11).

The resistance should be between 1 and 2 ohms.

OK: The solenoid coil resistance is OK. Continue to next step.

NOT OK: The shutoff solenoid is defective. Replace the solenoid. Then repeat Step 5.

Step 6. Check For Solenoid Short To Case

A. Clean or remove paint from a portion of the solenoid case so that a solid electrical connection can be made to the case.

B. Set the multimeter to measure resistance on the 2 Meg-ohm scale (2M).

C. Measure the resistance between the solenoid coil (Pin A of J11) and the solenoid case.

The resistance should be too high to measure. This is usually indicated by "OL" being displayed on the multimeter.

OK: The solenoid is OK. Continue to next step.

NOT OK: The solenoid is shorted to the case. Replace the solenoid. Then repeat Step 5.

Step 7. Check Solenoid Voltage From ECM

A. Reconnect shutoff solenoid connector (J11 to P11).

B. Install a 5-pin "T" at ECM/solenoids connector (J4/P4).

C. Start the engine.

D. Measure the shutoff solenoid voltage (Pin E to Pin B (ground) of the "T") while the engine is running.

The voltage should be between 1.5 and 2.5 VDC with the engine running.

OK: The ECM is supplying the correct voltages. Inspect the wiring harness between the ECM and the shutoff solenoid for damage or a broken connection. Repair as needed. Stop.

NOT OK: The ECM is not supplying the correct voltages to the solenoid. Replace the ECM. Stop.

P-224: Boost Pressure Sensor Test

The PEEC system monitors boost pressure with a sensor located in the transducer module. The boost sensor is supplied with electrical power by the 8 volt sensor supply and 5 volt reference voltages from the ECM. The sensor can only by replaced by replacing the transducer module.

The boost sensor is used to limit smoke emissions during acceleration. PEEC limits the amount of fuel injected until certain boost pressures are reached. It does this by converting boost pressure to "FRC Rack" (as shown on the ECAP status display). The FRC Rack (Fuel Ratio Control) is then a limit on rack position based on boost pressure.

NOTE: The Transducer Module used on the 3412 PEEC engine IS NOT interchangeable with the Transducer Module used on the 3406B PEEC truck engine.

Step 1. Check Electrical Connectors And Wiring

Check transducer module connector (J5/P5) and ECM/sensors connector (J3/P3) and wiring between them, being sure to:

* Check Connector lock rings.

* Perform 10 pound pull test on each pin or wire.

* Inspect wiring for damage or abrasion.

* Inspect connectors for damage or corrosion. Refer to P-201: Inspecting Electrical Connectors for details. Repair any damage, then continue with the next step.

Step 2. Visual Inspection

A. Verify that the boost and inlet air hoses are correctly installed (boost hose to top of intake manifold, and inlet air hose to clean air side of air filter).

B. Inspect the hoses for cracks, leaks or other damage. Make any necessary repairs.

Step 3. Calibrate Boost Sensor

Refer to procedure P-305: Boost Pressure Sensor Calibration to calibrate the boost sensor. The engine should be warmed up to operating temperature before calibration is performed.

The ECAP should indicate that the boost sensor was calibrated.

OK: Continue to next step.

NOT OK: Boost sensor voltages are not within specified range. Proceed to Step 6.

Step 4. Boost Sensor Pressure Test

A. Disconnect the boost pressure and inlet air pressure lines from the transducer module.

B. Connect the FT1906 Fuel Ratio Control Pressure Kit to the boost pressure port on the transducer module.

C. Observe the boost pressure display on the ECAP's Display Status Screen.

D. Close the pressure cock valve on the pressure test kit and apply 100 kPa (14.5 psi) to the boost pressure port.

E. Compare the readings on the ECAP with the pressure test kit.

The ECAP should show 0 kPa when no pressure is applied and agree within ± 7 kPa (1.0 psi) of the test kit.

OK: Boost sensor appears to operate normally. Continue to next step.

NOT OK: The ECM is not receiving a proper boost sensor signal. Reconnect boost and inlet air hoses. Proceed to Step 6.

Step 5. Leakage Test

A. Close the pressure cock valve on the pressure test kit and again apply 100 kPa (14.5 psi) to the boost pressure port.

B. Observe the boost pressure reading on the ECAP for 30 seconds before releasing the pressure.

C. Disconnect the pressure kit and reconnect the boost and inlet air hoses.

The leakage rate should not exceed 20 kPa (3 psi) in 30 seconds.

OK: The Boost pressure sensor is currently operating correctly. Stop.

NOT OK: Check for leaks in the hose or the test kit. If none are found, there is an internal leak in the transducer module. Replace the transducer module and calibrate the new boost sensor. Stop.

Step 6. Check Sensor Supply Voltage

A. Connect a 9-pin "T" at transducer module connector (J5/P5).

B. Measure the 8V sensor supply voltage (Pin H to Pin B), and the 5V reference voltage (Pin C to Pin B).

The 8V sensor supply voltage should be 8.0 ± 0.4 VDC and the 5V reference voltage should be 5 ± 0.25 VDC.

OK: Sensor is receiving proper supply voltage. Continue to next step.

NOT OK: There is a problem with the supply voltage. Refer to procedure P-221: Sensor Supply Voltage Test. Stop.

Step 7. Check Boost Pressure Signal At Transducer Module

A. Remove boost signal wire from the wiring harness connector (Wire E of J5) to isolate the boost sensor from the wiring harness.

B. Measure the boost sensor signal voltage at Pin E of the "T".

C. Reinsert Wire E in J5.

The boost sensor signal voltage should be between 0.7 and 1.2 VDC.

OK: The boost sensor is working properly. Continue to next step.

NOT OK: The boost pressure sensor is defective. Replace the sensor. Stop.

Step 8. Check Boost Pressure Signal At ECM

A. Connect a 9-pin "T" at ECM/sensors connector (J3/P3).

B. Remove boost pressure signal wire from the ECM connector (Wire E of J3) to isolate the ECM from the boost signal.

C. Measure the voltage between the boost pressure signal (Pin E) and ground (Pin B) of J3.

D. Reinsert Wire E in J3.

The boost pressure signal voltage should be between 0.7 and 1.2 VDC.

OK: The boost signal is good at the ECM. Continue to next step.

NOT OK: There is a problem with the wiring harness between the transducer module and the ECM. Inspect the wiring and connectors for damage or a broken connection. Repair as necessary. Stop.

Step 9. Check ECM

The previous step verified that a good boost signal is reaching the ECM.

The boost sensor should calibrate, display an accurate reading, and Diagnostic Code 25 should NOT be ACTIVE.

OK: The boost sensor is currently working correctly. Stop.

NOT OK: Be sure the wires removed previously have been replaced. If so, the ECM is not reading the boost signal. Replace the ECM.

P-225: Oil Pressure Sensor Test

The PEEC system monitors oil pressure with a sensor located in the transducer module. The oil pressure sensr is supplied with electrical power by the 8 volt sensor supply and 5 volt reference voltages from the ECM.

The oil pressure sensor can measure oil pressure from 0 kPa (0 psi) to 312 kPa (45 psi). Any pressure greater than 312 kPa is displayed as 312 kPa. The oil pressure measured by PEEC is about 10 kPa less than the gallery oil pressure.

After the engine has been running for ten seconds, PEEC will monitor oil pressure to ensure that it stays above certain limits. When it drops below the limits, PEEC will limit engine speed to 1,350 rpm, and generate Code 46 (Low Oil Pressure Warning). These limits are in the procedure for Diagnostic Code 46.

Note that PEEC uses the oil pressure only as an engine protection function. Lack of oil pressure does not prevent PEEC from starting the engine. PEEC will still try to start the engine even if oil pressure is low.

It is NOT NORMAL to get Diagnostic Code 24 with the power switch(es) ON, engine OFF, or to read 310 kPa (45 psi) with the power switch(es) ON, engine OFF.

Verify that the correct Transducer Module for 3412 (PEEC) Industrial Engine use is installed. The Transducer Module for the 3406B PEEC Diesel Truck Engine will fit, but different sensors are used. DO NOT install a truck module in and industrial engine. Sensor failure may result.

Step 1. Check Electrical Connectors And Wiring

Check transducer module connector (J5/P5) and ECM/solenoids connector (J3/P3) and wiring between them, being sure to:

* Check Connector lock rings.

* Perform 10 pound pull test on each pin or wire.

* Inspect wiring for damage or abrasion.

* Inspect connectors for damage or corrosion. Refer to P-201: Inspecting Electrical Connectors for details. Repair any damage, then continue with the next step.

Step 2. Check Oil Level

Check engine oil level and check that correct dipstick is installed. Also lok for fuel or coolant dilution of oil and oil leaks. Correct any problems.

Be sure that the engine is filled the correct level with SAE 10W-30 oil. If any other viscosity of oil is used, the information in the Engine Oil Pressure Graph does not apply.

Step 3. Check ECAP Display With Engine OFF

A. Turn power switch(es) ON, engine OFF.

B. Observe the "Oil Press" reading on the ECAP's "Display Status" screen.

The ECAP should display 0 kPa (0 psi) for oil pressure when the engine is not running. (A Diagnostic Code 46 may be shown with the engine not running. Only be concerned about a Diagnostic Code 46 when the engine is running).

OK: The sensor appears to be operating normally. Continue to next step.

NOT OK: The sensor is reading pressure where none exists. Proceed to Step 6.

Step 4. Check Pressure With Engine Running

A. Start the engine and warm it up to normal operating temperature.

B. Observe ECAP Status Screen and monitor "Oil Press".

Pressure should exceed 35 kPa (5 psi) within five seconds and fall within the "Acceptable Region" given on the Engine Oil Pressure Graph.

OK: The sensor appears to be operating normally. Stop.

NOT OK: Turn the engine OFF. Continue to Step 5.

Engine Oil Pressure Graph

NOTE: Make sure engine oil temperature does not go above 115°C (239°F).

Step 5. Check Actual Oil Pressure

Oil Manifold
(1) Pressure test location.

A. Connect the 1U5470 Engine Pressure Group to the main oil manifold at location (1).

B. Start the engine and run at low idle. If after five seconds the oil pressure does not exceed 35 kPa (5 psi), shut off the engine.

C. Push the throttle to the high idle position.

D. Check for oil leakage. Repair any leaks.

E. Compare the engine oil pressure to the acceptable range of oil pressure on the ENGINE OIL PRESSURE GRAPH.

The engine oil pressure reading on the Engine Pressure Group should exceed 35 kPa (5 psi) after five seconds and fall within the "Acceptable Region" given on the ENGINE OIL PRESSURE GRAPH.

OK: Actual oil pressure is OK. Continue to next step.

NOT OK: There is a problem with the engine oil pressure. Refer to 3412 (PEEC) Industrial Engine, Systems Operation Testing and Adjusting, Form No. SENR4652.

Step 6. Compare ECAP Display With 1U5470 Reading

A. Start engine and wait until oil pressure builds to at least 35 kPa (5 psi).

B. Vary the engine speed. Compare the oil pressure reading on the "Display Status" screen of the ECAP with the reading given by the 1U5470.

The oil pressure readings on the ECAP should be about equal to the readings on the 1U5470.

OK: The oil pressure sensor is currently operating correctly. Stop.

NOT OK: The sensor is not reading oil pressure correctly. Continue to the next step.

Step 7. Check Supply Voltage To Transducer Module

A. Turn power switch(es) ON, engine OFF.

B. Connect a 9-pin "T" at J5/P5.

C. Measure the 8V sensor supply voltage (Pin H to Pin B) and the 5V reference voltage (Pin C to Pin B).

The 8V sensor supply voltage should be 8.0 ± 0.4 VDC and the 5V reference voltage should be 5.0 ± 0.25 VDC.

OK: Voltage supply is OK. Continue to next step.

NOT OK: There is a problem with the voltage supply to the transducer module. Refer to P-221: Sensor Supply Voltage Test. Stop.

Step 8. Check Sensor Output

A. Remove oil pressure signal wire from the harness connector (Wire G of J5) to isolate signal.

B. Measure the oil pressure signal (Pin G to Pin B) of the "T" with the engine not running [power switch(es) ON], and with the engine running at 600 and at 1350 rpm.

C. Compare the measured voltages with the minimum sensor outputs given in Table A.

D. Reinsert Wire G in J5.

The oil pressure signal voltages should all be greater than the minimum values given in Table A.

OK: The oil pressure sensor is OK. Continue to the next step.

NOT OK: The oil pressure sensor is defective. Replace the transducer module and recalibrate the Boost Sensor. Stop.

Step 9. Check Oil Pressure Signal At ECM

A. Remove oil pressure signal wire from the ECM connector (Wire G of J3).

B. Connect a 9-pin "T" at ECM/sensors connector (J3/P3).

C. Measure the oil pressure signal voltage (Pin G to Pin B) of the "T" with the engine not running [power switch(es) ON], and at 600 rpm, and at 1350 rpm.

D. Compare the measured voltages with the minimum sensor outputs given in Table A.

E. Reinsert Wire G in J3.

The oil pressure signal voltages should all be greater than the minimum values given in Table A.

OK: Oil pressure signal is reaching the ECM. Continue to next step.

NOT OK: There is a problem with the harness between the transducer module and the ECM. Inspect the wiring harness and connectors for damage or a broken connection. Stop.

Step 10. Check ECM

A. Check that the wires removed in previous steps have been reinserted.

B. Start the engine and wait for proper oil pressure to build.

C. Check to see if Diagnostic Code 24 OR 46 is ACTIVE with the engine running.

Neither code ACTIVE: The oil pressure sensor and ECM are currently operating correctly. Stop.

Either code ACTIVE: The oil pressure signal is reaching the ECM but the ECM is not reading it. Replace the ECM. Stop.

P-226 Coolant Temperature Sensor Test

The Coolant Temperature Sensor measures the temperature of the engine coolant. The Electronic Control Module (ECM) uses this information to set the mode of engine operation.

Cold Mode is activated whenever coolant temperature is below 17°C (67°F). In Cold Mode, engine power is limited, injection timing is retarded and low idle is increased to approximately 1000 rpm, to improve warm-up time. Once activated, Cold Mode will continue until coolant temperature rises above 19°C (66°F), or until the engine has been running for 12 minutes. The ECM then causes the engine to leave Cold Mode, low idle speed is returned to the rpm set by the Customer Specified Parameters and normal engine operation is restored.

The Coolant Temperature Sensor can measure temperatures from less the -18°C (0°F) to about 65°C (149°F). Above 65°C (149°F), the signal voltage from the sensor goes above 5 volts. Since the ECM is unable to measure voltages above 5 volts, 65°C (149°F) is the maximum temperature that can be measured. The sensor operates on 8.0 volts DC and is common with the 8.0 volts supplied to the Transducer Module, Rack Position Sensor and the Engine Speed Sensor. All four also share a common return (ground) line, going back to the ECM through J3/P3 Pin B.

Step 1. Inspect Connectors, Wiring And Sensor

Check ECM/Sensor Connector (J3/P3) and Coolant Temperature Sensor Connector (J7/P7) and wiring between them, being sure to:

* Check Connector lock rings.

* Perform 10 pound pull test on each pin or wire.

* Inspect wiring for damage or abrasion.

* Inspect connectors for damage or corrosion. Refer to P-201: Inspecting Electrical Connectors for details. Repair any damage, then continue with the next step.

Step 2. Compare Temperature Shown On ECAP To Actual Coolant Temperature

A. Install ECAP on the engine.

B. Compare "COOLANT TEMP" shown on the ECAP status display to actual temperature as measured by water temperature gauge or by using the 6V9130 Temperature Adapter Group.

The two measurements should agree within ± 15°C (± 27°F).

OK: Coolant Temperature Sensor is working correctly. Stop.

NOT OK: There is a problem in the coolant temperature sensing circuit. Continue with next step.

Step 3. Check Supply Voltage To Sensor

A. With power switch(es) OFF, install the 3-Pin Breakout "T" on the harness side of the Coolant Temperature Sensor Connector (P7) only. Do not connect to J7 (sensor side) at this time.

B. Turn power switch(es) ON (engine OFF).

C. Measure sensor supply voltage between +8V (P7, Pin A) and Ground Analog (P7, Pin B), on the "T".

Supply voltage should be 8.0 ± 0.5 volts DC.

OK: Supply voltage is normal. Proceed to Step 5 to check signal voltage from the sensor.

NOT OK: The sensor is not receiving correct supply voltage. Continue to next step.

Step 4. Check Supply Voltage At ECM

A. With the power switch(es) OFF, install the 9-Pin Breakout "T" on the ECM/Sensors Connector J3 (ECM side) only. Do not connect to the harness side (P3) at this time.

B. Turn power switch(es) ON (engine OFF) and measure the sensor supply voltage between +8V (P3, Pin H) and Ground Analog (P3, Pin B).

Supply voltage should be 8.0 ± 0.5 volts DC.

OK: Supply voltage is present at the ECM but not at the sensor. Repair fault in harness between ECM and Coolant Temperature Sensor. Stop.

NOT OK: The ECM is not supplying correct voltage. Verify that the ECM is receiving proper battery voltage. If so, replace the ECM. Stop.

Step 5. Check Signal Voltage At Sensor

A. Install thermocouple probe. Use the instructions with the adapter group to determine the correct probe length for an accurate reading.

B. With the 3-Pin Breakout "T" still on the Coolant Temperature Sensor Connector (J7/P7), turn power switch(es) ON (engine OFF) and measure sensor signal voltage between Coolant (J7, Pin C) and Ground Analog (J7, Pin B) of the 3-Pin Breakout "T".

C. Use Table B in this procedure to determine coolant temperature from sensor voltage readings. Compare temperature found in Table B with temperature shown on the Temperature Adapter Group.

The temperature from Table B should agree within 10°C (18°F) with the temperature reading from the adapter group.

OK: Voltage is correct for observed temperature. Continue to next step.

NOT OK: Voltage is incorrect for observed temperature or signal is not present. Replace Coolant Temperature Sensor.

Step 6. Check Signal Through Harness To ECM

A. With power switch(es) OFF, install the 9-Pin Breakout "T" at the ECM/Sensors Connector (J3/P3).

B. Turn power switch(es) ON (engine OFF) and measure sensor signal voltage between Coolant (Pin J) and Ground Analog (Pin B) on the Breakout "T".

C. Use Table B of this procedure to determine coolant temperature from sensor voltage readings. Compare temperature found in Table B with temperature shown on the Temperature Adapter Group. The temperature from Table B should agree within 10°C (18°F) with the temperature from the adapter group.

OK: The signal is reaching the ECM. If Step 2 found that the ECM is not reading the correct temperature, then the ECM is defective, Replace the ECM. Stop.

NOT OK: The signal is not reaching the ECM. Check and repair the wiring harness between the Coolant Temperature Sensor and the ECM. Stop.

P-227: Atmospheric Pressure Sensor Test

The PEEC system monitors atmospheric pressure with a sensor located in the transducer module. The atmospheric pressure sensor is supplied with electrical power by the 8 volt sensor supply and 5 volt reference voltages from the ECM.

The atmospheric pressure sensor can measure atmospheric pressure from 0 kPa (0 psi) to 105 kPa (15 psi). Any pressure measured out of this range is displayed as 0 kPa (0 psi).

The atmospheric pressure sensor is used to limit rack based on altitude. This process, called atmospheric derating, actually involves limiting the rack position based on the atmospheric pressure. The limiting value is displayed on the ECAP.

Step 1. Check Electrical Connectors And Wiring

Check transducer module connector (J5/P5) and ECM/solenoids connector (J3/P3) and wiring between them, being sure to:

* Check Connector lock rings.

* Perform 10 pound pull test on each pin or wire.

* Inspect wiring for damage or abrasion.

* Inspect connectors for damage or corrosion. Refer to P-201: Inspecting Electrical Connectors for details. Repair any damage, then continue with the next step.

Step 2. Atmospheric Pressure Sensor Test

Compare atmospheric pressure sensor reading with current barometric pressure in working environment. Use a correctly calibrated barometer or obtain the barometric pressure from the local weather service.

The ECAP should agree within ± 5 kPa (.7 psi) of the reading obtained above.

OK Atmospheric sensor appears to be operating normally. Stop.

NOT OK The ECM is not receiving a proper atmospheric pressure sensor signal. Proceed to next step.

Step 3. Check Sensor Supply Voltage

A. Connect a 9-pin "T" at transducer module connector (J5/P5).

B. Measure the 8V sensor supply voltage (Pin H to Pin B), and the 5V reference voltage (Pin C to Pin B).

The 8V sensor supply voltage should be 8.0 ± 0.4 VDC and the 5V reference voltage should be 5 ± 0.25 VDC.

OK: Sensor is receiving proper supply voltage. Continue to next step.

NOT OK: There is a problem with the supply voltage. Refer to procedure P-221: Sensor Supply Voltage Test. Stop.

Step 4. Check Boost Pressure Signal At Transducer Module

A. Remove boost signal wire from the wiring harness connector (Wire E of J5) to isolate the boost sensor from the wiring harness.

B. Measure the boost sensor signal voltage at Pin E of the "T".

C. Reinsert Wire E in J5.

The boost sensor signal voltage should be between 0.7 and 1.0 VDC.

OK: The boost sensor is working properly. Continue to next step.

NOT OK: The boost pressure sensor is defective. Replace the sensor. Stop.

Step 5. Check Boost Pressure Signal At ECM

A. Connect a 9-pin "T" at ECM/sensors connector (J3/P3).

B. Remove boost pressure signal wire from the ECM connector (Wire E of J3) to isolate the ECM from the boost signal.

C. Measure the voltage between the boost pressure signal (Pin E) and ground (Pin B) of J3.

D. Reinsert Wire E in J3.

The boost pressure signal voltage should be between 0.7 and 1.0 VDC.

OK: The boost signal is good at the ECM. Continue to next step.

NOT OK: There is a problem with the wiring harness between the transducer module and the ECM. Inspect the wiring and connectors for damage or a broken connection. Repair as necessary. Stop.

Step 6. Check ECM

The previous step verified that a good boost signal is reaching the ECM.

The atmospheric pressure sensor should display an accurate reading, and Diagnostic Code 26 should NOT be ACTIVE.

OK: The boost sensor is currently working correctly. Stop.

NOT OK: Be sure the wires removed previously have been replaced. If so, the ECM is not reading the boost signal. Replace the ECM.

P-230: Dynamic Rack Controls Test

The primary function of the PEEC system is to electronically govern the engine. The PEEC governor senses engine speed (using the Engine Speed Sensor on the fuel pump camshaft), then controls the fuel rack to achieve a desired rpm. This test is used to determine if the PEEC governor is properly controlling the fuel rack.

Because this test requires monitoring several internal PEEC variables, the ECAP should be used. The variables displayed on the ECAP "Status Display" which are used in this test are:

* Desired RPM

The rpm that the PEEC governor is trying to maintain. It is based on throttle setting, engine speed, Customer Specified Parameters, and certain diagnostic codes.

* Desired Rack

The position where the ECM wants to move the rack, based on the PEEC governor trying to maintain "Desired RPM". "Desired Rack" will not go farther than the "FRC Rack" or "Rated Rack".

* Actual Rack

The ECM's interpretation of the Rack Position Sensor signal represents actual position of the rack, assuming the sensor signal is valid. If the rack controls (solenoid, servo, sensor, etc.) are working properly, "Actual Rack" should follow "Desired Rack".

* FRC Rack

The rack limit based on the Fuel-Air-Ratio Control (FRC). FRC Rack increases with boost pressure (as sensed by the Boost Sensor in the Transducer Module). This effectively limits the fuel injected into the cylinders until there is enough air present in the cylinders (as indicated by boost pressure) to cleanly burn the fuel. "Desired Rack" will never go past "FRC Rack".

* Rated Rack

The rack limit which defines the horsepower and torque curves for the engine based on engine rpm. This limit is derived from maps programmed into the Personality Module by the factory.

Step 1. Verify Normal Rack Operation At Idle

A. Start the engine.

B. Monitor Desired RPM, Desired Rack, and Actual Rack on the ECAP "Status Display".

Desired RPM should be equal to the programmed Low Idle RPM and steady. The Actual Rack should follow Desired Rack within ± .5 mm (.02 in) (Note that the lag in the ECAP "Status Display" causes some normal differences between the two readings). For a typical engine idling with normal accessory loads, both readings should be around 3.00 mm to 4.00 mm (.12 to .16 in).

OK: PEEC is able to control the rack properly at idle. Continue with Step 2.

NOT OK: * If desired RPM is too high or unstable, follow P-211: Throttle Control Sensor Test. Stop.

* If the rack readings are not as specified, follow P-231: Rack Position Sensor Test, and P-232: Rack Solenoid (BTM) Test. Stop.

Step 2. Verify Normal Rack Operation Under Load

A. Load the engine, using a dynometer.

B. Monitor Desired Rack, Rated Rack, and FRC Rack.

Desired Rack should reach Rated Rack with the engine fully loaded.

OK: If the Rack Position Sensor is calibrated (refer to P-231: Rack Position Sensor Calibration), then PEEC is moving the rack to the specified position as it should. If problems persist, the cause IS NOT the rack controls. Refer to the procedure best describing the symptom. Otherwise, Stop.

NOT OK: * If Desired Rack is limited to FRC Rack, PEEC is sensing low boost pressure. Check for problems in the air intake system, then follow P-224: Boost Pressure Sensor Test.

* If Desired Rack is limited to some other value below Rated Rack, PEEC is intentionally limiting power or rpm for some reason. Refer to P-107: Low Power/Engine RPM Restricted, to determine why. Stop.

P-231: Rack Position Sensor Test

The rack position sensor is magnetically attached to the fuel rack. The sensor is supplied with 8.0 volts for operation, and uses 5.0 volts for sensor reference. The signal output of 0.3 volts to 5.25 volts is read by the ECM as rack position of 0 to 15.06 mm (0 to .59 in). Fuel shutoff is 1.8 ± .05 mm (.07 ± .02 in).

Step 1. Check Electrical Connectors And Wiring

A. Check transducer module connector (J5/P5), and ECM/sensors connector (J3/P3) and wiring between them, being sure to:

* Check Connector lock rings.

* Perform 10 pound pull test on each pin or wire.

* Inspect wiring for damage or abrasion.

* Inspect connectors for damage or corrosion. Refer to P-201: Inspecting Electrical Connectors for details. Repair any damage, then continue with the next step.

B. Remove the rear cover from the governor.

C. Inspect rack sensor connector (J8/P8) and wiring for damage or incorrect attachment. Repair any damage. All wires in governor should be covered by protective sheathing.

Step 2. Check Rack Sensor Calibration

Refer to procedure P-231: Rack Position Sensor Calibration to check the rack sensor calibration. Recalibrate if needed. If sensor is unable to calibrate, proceed to Step 4.

Step 3. Check Rack Position Reading On ECAP

A. Remove the Rack Solenoid (BTM).

B. Turn power switch(es) ON, engine OFF.

C. Move the rack back and forth by hand and observe the "Rack Pos" reading on the ECAP "Display Status" screen. The manual shutoff lever may have to be rotated clockwise to free up the rack.

The reading on the ECAP should be about 0.4 to 1.1 mm (.02 to .04 in) in the FUEL OFF position and increase to about 14.0 to 17.5 mm (.55 to .69 in) in the full FUEL ON position.

OK: The rack sensor is currently operating correctly. Stop.

NOT OK: Continue to next step.

Step 4. Check Voltage Supply To Rack Sensor

A. Connect a 5-pin "T" at rack sensor connector (J8/P8).

B. Measure the 8V sensor supply voltage (Pin A to Pin B). and the 5V reference voltage (Pin C to Pin B).

The 8V sensor supply voltage should be 8 ± 0.4 VDC and the 5V reference voltage should be 5 ± 0.25 VDC.

OK: The sensor is receiving the proper supply voltages. Continue to next step.

NOT OK: There is a problem with the sensor supply voltage. Refer to P-221: Sensor Supply Voltage Test to troubleshoot.

Step 5. Check Rack Signal At Rack Sensor Connector

A. With the 5-pin "T" still at the rack sensor connector (J8/P8), remove the rack signal wire from the transducer side (Pin D of J8).

B. Measure the rack signal voltage (Pin D to Pin B) of the "T" while moving the rack back and forth by hand.

C. Reinsert Wire D in J8.

The voltage should be less than 2.0 VDC in the FUEL OFF position and smoothly increase to more than 4.0 VDC when the rack is moved all the way to FUEL ON.

OK: Rack sensor is OK. Continue to next step.

NOT OK: Rack sensor is not operating properly. Verify that the sensor plunger is in contact with the rack magnet, and that the epoxy on the magnet is in place. If so, replace the rack position sensor. Stop.

Step 6. Check Rack Signal At Transducer Module Connector

A. Connect a 9-pin "T" at transducer module connector (J5/P5).

B. Remove rack signal wire (on Pin D) from connector (J5) (harness side).

C. Measure the rack signal voltage (Pin D to Pin B) of the "T" while moving the rack back and forth by hand.

D. Reinsert Wire D in J5, remove the "T", and reconnect transducer module connector (J5/P5).

The voltage should be less than 2.0 VDC in the FUEL OFF position and smoothly increase to more than 4.0 VDC when the rack is moved all the way into the FUEL ON range.

OK: The rack signal is getting through the transducer module. Continue to next step.

NOT OK: The rack signal is NOT getting through the transducer module. Check for damage in the connectors and wiring coming out of the transducer module. If none is found, replace the transducer module. Stop.

Step 7. Check Rack Signal At ECM

A. Connect a 9-pin "T" at ECM/sensors connector (J3/P3).

B. Remove rack signal wire from ECM connector (Wire D of J3).

C. Measure the voltage between rack signal voltage (Pin D) and ground (Pin B) of the "T" while moving the rack back and forth by hand.

D. Reinsert Wire D in J3.

The voltage should be less than 2.0 VDC in the FUEL OFF position and smoothly increase to more than 4.0 VDC when the rack is moved all the way into the FUEL ON range.

OK: The rack signal is reaching the ECM. Continue to next step.

NOT OK: The rack signal is NOT reaching the ECM. Inspect the wiring harness and connectors for damage or broken connection between the transducer and the ECM. Stop.

Step 8. Check ECM

A. Repeat Step 3 to determine if the ECM is reading the rack signal.

B. Check to see if Diagnostic Code 22 is ACTIVE.

The ECAP should show a valid rack position and Diagnostic Code 22 should NOT BE ACTIVE.

OK: The rack position sensor circuit is currently working correctly. Stop.

NOT OK: The ECM is not reading the rack signal. Recheck wires exiting the ECM to J3 for damage and repair as needed. If no damage is found, replace the ECM. Stop.

P-232: Rack Solenoid (BTM) Test

The Rack Solenoid [or brushless torque motor (BTM)] is used to move the engine's fuel rack. The BTM is spring-actuated to the FUEL OFF position. The BTM will move into the Fuel ON range when a voltage is applied.

Step 1. Check Electrical Connectors And Wiring

Check Rack Solenoid (BTM) connector (J10/P10) and ECM/solenoids connector (J4/P4) and wiring between them, being sure to:

* Check Connector lock rings.

* Perform 10 pound pull test on each pin or wire.

* Inspect wiring for damage or abrasion.

* Inspect connectors for damage or corrosion. Refer to P-201: Inspecting Electrical Connectors for details. Repair any damage, then continue with the next step.

Step 2. Remove And Inspect Rack Solenoid (BTM)

A. Remove the Rack Solenoid (BTM).

B. Check rack and rack servo for sticking or binding.

C. Inspect the Rack Solenoid (BTM) arm for damage, and for signs of binding in the rack servo sleeve.

The Rack Solenoid (BTM) arm should not be loose, and should encounter resistance from the spring as it is moved.

OK: Continue to next step.

NOT OK: Replace Rack Solenoid (BTM) if arm is damaged. Stop.

Step 3. Rack Solenoid (BTM) Sweep Test

A. Turn power switch(es) ON, engine OFF.

B. Apply a continuous ground to Pin F of connector P2.

After a few seconds, the Rack Solenoid (BTM) arm should begin to sweep smoothly clockwise. Once it moves slightly past the dot on the Rack Solenoid (BTM) face plate, it should pause briefly, and then sweep back to the OFF stop.

OK: The Rack Solenoid (BTM) is currently operating properly. Stop.

NOT OK: Proceed to next step.

Step 4. Check Rack Solenoid (BTM) Resistance

A. Connect P10 [Rack Solenoid (BTM) side only] to a 3-pin "T".

B. Measure the resistance between Rack Solenoid (BTM) (Pin A) and ground (Pin B) of the "T".

The resistance should be between 1 and 2 ohms.

OK: Rack Solenoid (BTM) resistance is OK. Continue to next step.

NOT OK: Rack Solenoid (BTM) is defective. Replace Rack Solenoid (BTM). Stop.

Step 5. Check Voltage To Rack Solenoid (BTM) During Sweep Test

A. Connect a 3-pin "T" at Rack Solenoid (BTM) Connecter (J10/P10).

B. Measure the voltage between Rack Solenoid (BTM) (Pin A) and ground (Pin B) of the "T".

C. Apply a continuous ground to Pin F of connector P2.

The voltage should begin at zero, increase to 3.6 ± 0.3 VDC and then decrease to zero VDC.

OK: The Rack Solenoid (BTM) is receiving voltage but is not moving. Replace the Rack Solenoid (BTM). Stop.

NOT OK: The Rack Solenoid (BTM) is not receiving the proper voltages. Continue to next step.

Step 6. Check Voltage From ECM During Sweep Test

A. Connect a 5-pin "T" at ECM/solenoids connector (J4/P4).

B. Measure the voltage between rack solenoid Rack Solenoid (BTM) signal (Pins C) and ground (Pin B) of the "T".

C. Apply a continuous ground to pin F of connector P2.

The voltage should begin at zero, increase to 3.6 ± 0.3 VDC and then decrease to zero VDC.

OK: The ECM is supplying proper voltages, but the Rack Solenoid (BTM) is not receiving them. Inspect the wiring and connectors between J10/P10 and J4/P4 for damage or a broken connection. Stop.

NOT OK: The ECM is not supplying the proper voltages. Verify that the ECM is getting battery power (P-210). If OK, there is a problem with the ECM. Replace the ECM. Stop.

P-240: Checking Engine Timing And Timing Advance

8T5300 Timing Indicator Group
(1) 8T5250 Engine Timing Indicator. (2) 5P7366 Cable Assembly. (3) 6V2197 Magnetic Transducer. (4) 5P7362 Cable. (5) 6V2100 & 6V3093 Transducer Adapters. (6) 8D4644 Fuse.

The 8T5300 Timing Indicator Group with an 8T5301 Diesel Timing Adapter Group, can be used to measure fuel injection timing for the engine.

8T5301 Diesel Timing Adapter Group
(7) 5P7437 Adapter. (8) 6V2198 Cable. (9) 5P7436 Adapter. (10) 6V7910 Transducer. (11) 5P7435 Adapter. (12) 6V3016 Washer.

6V3121 Multitach Group

The 6V3121 Multitach Group can measure engine speed from a magnetic pickup on the flywheel housing. It also has the ability to measure engine speed from visual engine parts in rotation.

Special Instruction, Form No. SEHS7807 is with the 6V3121 Multitach Group and gives instructions for the test procedure.

The 6V4950 Injection Line Speed Pickup Group is another diagnostic tool accessory that can be used with the 6V2100 Multitach. It can be used on all Caterpillar Diesel Engines Equipped with 6 mm (.25 in) single wall fuel injection lines. With this pickup group, engine speed can be measured quickly, automatically and with an accuracy of ± 1 rpm.

Special Instruction, Form No. SEHS8029 is with the group and gives instructions for use of the 6V4950 Injection Line Speed Pickup Group.

When checking the dynamic timing on an engine that has a mechanical advance, Caterpillar recommends that the serviceman calculate and plot the dynamic timing specifications first on a worksheet like Form No. SEHS8140. These worksheets are available in pads of 50 sheets, order Form No. SEHS8140. Refer to Special Instructions Form No. SEHS8580 for information required to calculate the timing curve. For the correct timing specifications to use, see the Engine Information Plate for the performance specification number and make reference to the Fuel Setting And Related Information Fiche.

NOTE: For more information on acceptable tolerances for dynamic fuel injection timing, see Service Magazines dated 4-1-85 and 10-28-85.

After the timing values are calculated and plotted, the dynamic timing should be checked with the 8T5300 Engine Timing Indicator Group. To do this, the serviceman must operate the engine from 1000 rpm (base rpm) to high idle and from high idle to 1000 rpm (base rpm). Unstable readings are often obtained below 1000 rpm. He must record the dynamic timing at each 100 rpm and at the specified speeds during both acceleration and deceleration. Then he should plot the results on the worksheet.

Inspection of the plotted values will show if the fuel injection timing is within specification and if it is advancing correctly.

Engine speed may be measured on the ECAP, or by use of the 6V3121 Multitach Group, or on the instrument panel tachometer.

1. Make reference to Special Instruction Form No. SEHS8580 for complete instructions and calibration of the 8T5300 Timing Indicator Group.

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The engine must be stopped before the timing indicator group is installed. A high pressure fuel line must be disconnected and a probe must be installed in the flywheel housing.

Transducer In Position
(10) Injection transducer. (13) Fuel injection line for No. 1 cylinder.

2. Disconnect fuel infection line (13) for No. 1 cylinder. Slide the nut up and out of the way. Put 5P7436 Adapter (9) in its place and turn the adapter onto the fuel pump bonnet until the top of the bonnet threads are approximately even with the bottom of the "window" in 5P7436 Adapter (9).

3. Put 5P7435 Tee Adapter (11) on injection transducer (10) and put the end of 5P7435 Tee Adapter (11) in the "window" of 5P7436 Adapter (9).

4. Move the end of fuel line (13) down on top of 5P7435 Tee Adapter (11). Hold fuel line (13) in place with 5P7437 Adapter (7) and tighten to a torque of no more than 40 N·m (30 lb ft).

5. Remove plug (14) from timing hole in flywheel housing. Install transducer adapter (5) into the timing hole and tighten just a small amount more than finger tight.

Timing Hole Location
(14) Plug.

6. Push magnetic transducer (3) into adapter (5) until it makes contact with the flywheel. Pull it back out 1.5 mm (.06 in) and finger tighten the knurled locknut.

Transducer In Position
(3) Magnetic transducer.

7. Connect the cables from the transducer to engine timing indicator (1). Calibrate and make adjustment. For calibration procedure, refer to Special Instruction Form No. SEHS8580.

8. Start the engine and let it reach operating temperature. Then run the engine at approximately one-half throttle for eight to ten minutes before measuring timing.

9. Run the engine at the speeds required to check low idle and high idle. Record the engine timing indicator readings, If the engine timing is not correct, make reference to Fuel System Adjustment (On Engine), Measuring Fuel Injection Pump Timing Dimension for static adjustment of the fuel injection pump drive in the 3412 (PEEC) Industrial Engine Systems Operation Testing & Adjusting manual, Form No. SENR4652.

10. If the timing advance is still not correct, or if the operation of the advance is not smooth, make a repair or replacement of the automatic advance unit. There is no adjustment to the unit.