Usage:
STEP 1. Check Rack Position Sensor Calibration
Test Procedure:
Verify Rack Position Sensor Calibration using Service Procedure D.
Expected Results:
Rack sensor is properly calibrated.
STEP 2. Check Rack Position Sensor Supply Voltage
Test Procedure:
Disconnect the Rack Position Sensor from the engine wiring harness. At the harness side of the connector, measure the DC voltage between pins 1 and 2.
Expected Results:
Voltage is between 12 VDC and 25 VDC.
STEP 3. Check Engine Performance
Test Procedure:
Cycle the engine back and forth between a high notch and idle several times while observing the diagnostic lamps at the Locomotive Control box.
Expected Results:
The diagnostic lamps continue to display the rack position sensor fault. (If other faults are displayed, the rack position sensor fault continues to be displayed at its allotted time.) The engine speed is not erratic. Acceleration and deceleration are smooth. The engine picks up load smoothly.
STEP 4. Check Wiring Harness Between Rack Sensor and Control Box
Test Procedure:
Shutdown engine. Disconnect Rack Position Sensor from engine wiring harness. Disconnect Connector J2 from box. Place a jumper wire between harness connector J2 pins 3 and 4. Measure the resistance between pins 1 and 3 of the rack position sensor connector at the wiring harness.
Expected Results:
The resistance measured is less than 5 ohms.
STEP 5. Check Sensor Ground Wire
Test Procedure:
Remove jumper wire from connector J2 pins 3 and 4. Connect jumper wire between connector J2 pins 4 and 5. Measure the resistance between pins 2 and 3 of the rack sensor connector at the wiring harness.
Expected Results:
The resistance measured is less than 5 ohms.
STEP 6. Check Harness for Short Circuits
Test Procedure:
Remove jumper wire from connector J2 pins 4 and 5. Check for short circuits between the harness side rack position sensor connector pins and other harness wires.
Expected Results:
There are no short circuits in the wiring harness.
STEP 7. 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 8. Resistance Check of Actuator and Leads
Test Procedure:
Remove Connector J2 from Control Box. Measure the resistance between J2 pins 1 and 2 at the wiring harness.
Expected Results:
Measured resistance should be between 30 and 40 ohms.
STEP 9. 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.)
NOTE: If sure-seal connector is not used and wire connection is crimped, the wires will have to be cut. Cut the wire at each side of the crimp connection to remove a potential problem.
Expected Results:
Measured resistance to be between 30 to 40 ohms.
STEP 10. Actuator Lead Resistance Check
Test Procedure:
Measure resistance of each lead between: Pin A and J2 connector pin 1. Pin B and J2 connector pin 2.
Expected Results:
Measured resistance of each lead is less than 1 ohm.
STEP 11. Check Actuator Oil Pressure Output
Test Procedure:
With engine stopped, remove the test pressure plug from actuator and install 6V2044 Test Pressure Gauge. Crank 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 12. 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.
- b. Plugged drain.
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 1. Check Current Sense Input
Test Procedure:
With the engine running and free to load, set the throttle to apply light load. Measure the generator current. With connector J1 connected to the Control box, measure the DC voltage applied by the locomotive electrical system to Connector J1 pin 10 (Current Sense Input) with respect to - Battery Voltage.
Expected Results For AC generators:
The voltage is less than 55 VDC and is:
Expected Results For DC generators:
The voltage is less than 55 VDC and is:
Step 1. Check Voltage Sense Input
Test Procedure:
With the engine running and free to load, set the throttle to apply light load. Measure the generator voltage. With Connector J1 connected to the Control box, measure the DC voltage applied by the locomotive electrical system to Connector J1 pin 11 (Voltage Sense Input) with respect to - Battery Voltage.
Expected Results For AC generators:
The voltage is less than 55 VDC and is:
Expected Results For DC generators:
The voltage is less than 55 VDC and is:
