Caterpillar Electronic Locomotive Control System II Caterpillar

Problem Number 18 Engine Shuts Down

Usage:

STEP 1. Check Electronic Locomotive Control Box

Test Procedure:

Observe the diagnostic lamps which are visible through the lens on the control box lid.

Expected Results:

SHUTDOWN lamp ON. WHEEL SLIP and GENERATOR LOAD lamps may be ON or OFF depending on locomotive design. All other lamps OFF.

Fig. 1 SHUTDOWN LAMP

Fig. 2 BOX FAULT

Fig. 3 TURN CAL ADJUST OUT

Fig. 4 TURN CAL ADJUST IN

Fig. 5 CAL ADJUST CORRECT

Fig. 6 PERSONALITY MODULE FAULT

Fig. 7 ENGINE SPEED SENSOR FAULT

STEP 2. Check Electronic Locomotive Control Box

Test Procedure:

Disconnect connector J1 (VE connector) from control box. Reconnect and observe the diagnostic indicator lamps.

Expected Results:

All lamps turn ON for 5 seconds. SHUTDOWN lamp remains ON.

STEP 3. Check Power to Electronic Control Box

Test Procedure:

Disconnect connector J1 (VE connector) from control box. Set a digital multimeter (Cat Service Tool 6V3030) on the 200 VDC scale and connect the probes to measure DC voltage. Use this to measure the DC voltage between pins 8 and 9 of connector J1 at the wiring harness.

Expected Results:

The voltage is greater than 24 VDC and less than 150 VDC.

STEP 4. Check Personality Module CAL Switch

Test Procedure:

Remove the fitting covering the CAL switch on the Personality Module. (See Service Procedure D.) Use a small screwdriver to turn the switch clockwise (away from the CAL marking). Replace the fitting covering the CAL switch. Observe the diagnostic lamps in the Locomotive Control box.

Expected Results:

The CAL ADJ (TURN CAL ADJ OUT, CAL ADJ CORRECT and TURN CAL ADJ IN) lamp codes are all OFF.

STEP 5. Attempt to Start Engine

Test Procedure:

Attempt to start the engine in the usual manner.

Expected Results:

Engine starts and runs normally.

STEP 6. Check for intermittent signals

Test Procedure:

With the engine running in the same manner as when the unexpected shutdown occurred, observe the lamps on the diagnostic lamps on the control box lid.

Expected Results:

As the engine begins to shutdown, the SHUTDOWN lamp turns ON.

STEP 7. Check Operator Shutdown Input

Test Procedure:

With the Locomotive Control box connected to the wiring harness, and the engine running, measure the DC voltage applied by the locomotive electrical system to the operator shutdown input (applied to connector J1 pin 12) with respect to the interface (-) battery voltage (applied to connector J1 pin 15) when the SHUTDOWN lamp turns ON. Also measure the interface (+) battery voltage (connector J1, pin 14) with respect to interface (-) battery voltage.

NOTE: It is very important to note even a momentary reduction of voltage to this input as a momentary drop in voltage will cause a shutdown.

Expected Results:

The DC voltage applied to the operator shutdown input is within 8 VDC of the interface (+) battery voltage and is constant.

STEP 7.5 Check Notch Code Inputs

Test Procedure:

With the Locomotive Control box connected to both connectors (J1 and J2) and the engine being cranked, measure the DC voltage applied by the locomotive electrical system to the Notch Code Inputs (Connector J1, pins 16, 17, 18 and 19) with respect to the Interface (-) Battery Voltage (at Connector J1, pin 15). Also measure Interface (+) Battery Voltage (at Connector J1, pin 14) with respect to Interface (-) Battery Voltage.

Expected Results:

With "high" inputs (code "1's") defined as being within 8 VDC of the Interface (+) Battery Voltage, and "low" inputs (code "0's") defined as being less than 2 VDC with respect to Interface (-) Battery Voltage, the notch code does not correspond with the shutdown code.

STEP 8. Check For Actuator Travel

Test Procedure:

Run the engine in the manner that caused the unexpected shutdown. Observe the actuator while the engine unexpectedly shuts down.

Expected Results:

Actuator movement to FUEL ON position.

STEP 9. Check Fuel Shut-off Systems

Test Procedure:

With engine running, visually check any fuel shut-off systems connected between the control box and the actuator. Refer to system wiring diagram.

Expected Results:

All fuel shut-off systems are closed and do not limit current flow to actuator.

STEP 10. Check Rack Actuator Signals

Test Procedure:

Connect a digital multimeter (Caterpillar Service Tool 6V3030) to measure DC volts on the 20V scale. Use this to measure the voltage between J2-1 and J2-2 while the engine is running. Measure the voltage that occurs as the engine begins to shutdown unexpectedly.

Expected Results:

Voltage from control box is greater than 8 VDC.

STEP 11. Manual Linkage Check

Test Procedure:

With engine stopped, manually move actuator lever and linkage to full FUEL ON position against stop screw.

Expected Results:

Linkage should move through full travel until it is against stop screw without binding or excessive force.

STEP 12. Check Actuator Oil Pressure Output

Test Procedure:

With engine stopped, remove the test pressure plug from actuator and install 6V2044 Test Pressure Gauge. Start the engine and read pressure from test pressure gauge.

NOTE: For correct pressure range, see ELECTRIC GOVERNOR ACTUATOR SPECIFICATIONS in Service Procedure B.

Expected Results:

Specified oil pressure with constant output.

STEP 13. Check Actuator Oil Supply and Mechanical Drive

Test Procedure:

See Service Procedure B to check actuator functions that follow:

A. Correct oil supply.

B. Plugged drain.

C. Oil too thin.

D. Drive has rotation.

E. Correct direction of rotation.

F. Damage to Coupling or Splines.

Engine compartment oil sump must be full, and suction line must be open and without air leaks (caused by faulty gaskets or loose fittings). Actuator oil drain must drain freely.

Expected Results:

To find problem with the actuator drive or oil circuit.

STEP 14. Resistance Check of Actuator and Leads

Test Procedure:

Shutdown engine. Disconnect connector J2 from the Electronic Locomotive Control box. Measure the resistance between pins 1 and 2 of the wiring harness side of connector J2.

Expected Results:

Measured resistance should be between 30 and 40 ohms.

STEP 15. Actuator Coil Resistance Check

Test Procedure:

Disconnect wiring connector from actuator. Put a jumper across pins C and D of connector. Measure the actuator coil resistance across connector pins A and B. (See Service Procedure B Fig. 2.)

Expected Results:

Measured resistance to be between 30 to 40 ohms.

STEP 16. Actuator Lead Resistance Check

Test Procedure:

Measure resistance of each lead between: Pin A and harness connector J2 pin 1. Pin B and harness connector J2 pin 2.

Expected Results:

Measured resistance of each lead is less than 1 ohm.

STEP 17. Actuator Coil Resistance Check

Test Procedure:

Disconnect wiring connector from actuator. Put a jumper across pins C and D of connector. Measure the actuator coil resistance across connector pins A and B. (See Service Procedure B Fig. 2.)

Expected Results:

Measured resistance to be between 30 to 40 ohms.