Caterpillar Electronic Locomotive Control System II Caterpillar

Problem Number 13 Engine Overspeeds

Usage:

STEP 1. 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, excessive force or excessive backlash. With linkage disconnected from actuator, the weight of the linkage should cause it to move toward fuel shutoff.

STEP 2. Check Control Box Diagnostic Lamps

Test Procedure:

Observe the diagnostic indicator lamps visible at the cover of the Electronic Locomotive Control box.

Expected Results:

RACK POSITION SENSOR FAULT is indicated. The yellow SHUTDOWN lamp is ON.

Fig. 1 RACK POSITION SENSOR FAULT

Fig. 2 SHUTDOWN LAMP

Fig. 3. CONTROL BOX FAULT

Fig. 4. PERSONALITY MODULE FAULT

Fig. 5. SPEED SENSOR FAULT

Fig. 6. VOLTAGE SENSE FAULT

Fig. 7. CURRENT SENSE FAULT

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. Verify Failsafe Circuit Operation

Test Procedure:

Stop the engine. Connect a digital multimeter (Caterpillar Service Tool 6V3030) to measure DC volts. With the Control box connected, measure the actuator voltage at Connector J2 pins 1 and 2.

Expected Results:

Voltage is zero.

STEP 5. Check For Control Box Signal to Actuator

Test Procedure:

Disconnect Connector J2 from Control box. Measure the DC voltage between Connector J2 pins 1 and 2.

Expected Results:

Voltage is zero.

STEP 6. Check Protection System Components

Test Procedure:

Disconnect electrically operated protection system components. Measure the DC voltage across Connector J2 pins 1 and 2.

Expected Results:

Voltage is zero.

STEP 7. Check Personality Module Specifications

Test Procedure:

Verify that the Personality Module in use has the correct part number and review the customer specified settings for that part number.

Expected Results:

The correct Personality Module is in use.

STEP 8. Check Actuator Oil Pressure Output

Test Procedure:

With engine stopped, remove the test pressure plug from actuator and install 6V2044 Test Pressure Gauge. Now start the engine and run at Low Idle. Read pressure from test pressure gauge.

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

Expected Results:

Oil pressure should be at relief setting of 2750 kPa (400 psi) with constant output.

STEP 9. 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 fitting). Actuator oil drain must drain freely.

Expected Results:

To find problem with the actuator drive or oil circuit.