PUMP-FUEL INJECTION 3081905 - Caterpillar

Do not operate or work on this machine unless you have read and understand the instructions and warnings in the Operation and Maintenance manuals. Failure to follow the instructions or heed the warnings could result in injury or death. Contact your authorized dealer for replacement manuals. Proper care is your responsibility.
Turn the battery disconnect switch and the key start switch to the OFF position.
At the PCS ECM, use the spoon type 7X-1710 Multimeter Probes to check the duty cycle of the PCS lift position sensor circuit. Insert the positive probe along the lift position sensor wire at connector contact J2-34 (wire C530-BU(Blue)) and insert the negative probe along the return circuit wire at contact J1-13 (wire 251-BK(Black)).
Turn the battery disconnect switch to the ON position.
Turn the key start switch to the ON position.
Start the machine.
Observe the duty cycle measurement while operating the lift through full travel. Expected Result:The duty cycle of the lift position sensor circuit should vary between no less than 3% and no more than 97% while the lift is operated through full travel.Results:
YES - The duty cycle of the lift position sensor signal varies between no less than 3% and no more than 97% during the full travel of the lift. This indicates that the lift position sensor signal is correct. Proceed to Test Step 2.
NO - The duty cycle of the lift position sensor signal does not vary between no less than 3% and not more than 97% during the full travel of the lift. There is a problem in the lift position sensor circuit. Proceed to Test Step 2.Test Step 2. CHECK THE INTEGRITY OF THE HARNESS BY CHECKING THE DUTY CYCLE OF THE LIFT POSITION SENSOR CIRCUITWhen the engine is off and the key start switch is in the ON position, the PWM duty cycle of the PCS lift position sensor duty cycle should be steady at a percentage that is between no less than 3% and no more than 97%.
Turn the battery disconnect switch and the key start switch to the OFF position.
At the PCS ECM, use the spoon type 7X-1710 Multimeter Probes to check the duty cycle of the PCS lift position sensor circuit. Insert the positive probe along the lift position sensor wire at connector contact J2-34 (wire C530-BU(Blue)) and insert the negative probe along the return circuit wire at contact J1-13 (wire 251-BK(Black)).
Turn the battery disconnect switch to the ON position.
Turn the key start switch to the ON position.
Check the duty cycle of the lift position sensor circuit at the ECM connector.
While observing the duty cycle measurement, wiggle the machine wiring harness close to the PCS ECM connectors. Expected Result:The duty cycle of the lift position sensor circuit should be steady at a percentage that is between no less than 3% and no more than 97% while the wiring harness is manipulated.Results:
YES - The duty cycle of the lift position sensor signal is steady between no less than 3% and no more than 97% during the