PLATE-RETAINER 3711196 - Caterpillar

Illustration 1 g01117474
Sensor Supply VoltageThis diagnostic code is recorded when the ECM reads the voltage of the sensor supply circuit as below normal range. The sensor supply is a power supply that is internal to the ECM. The sensor supply provides +8 DCV to operate the PWM buffers. The ECM monitors this output voltage and records a diagnostic code when the voltage is is less than 7.5 DCV.The possible causes of this diagnostic code are:
The +V circuit is shorted to the return circuit or frame ground.
A PWM buffer is malfunctioning.
The ECM has failed. This is unlikely.System Response:The results of this diagnostic code are:
Improper operation of PWM buffers which could cause the conveyors and augers to perform in an unpredictable manner.Note: Ensure that the diagnostic code CID 061 FMI F04 for the sensor is on hold and that the diagnostic code present indicator on the ECM display is ON. This procedure can cause other diagnostic codes to be recorded. Ignore these created diagnostic codes. When this procedure is completed, clear the created diagnostic codes.Test Step 1. Check PWM Buffer
Turn the key start switch to the ON position. Do not start the engine.
While observing the status of the diagnostic code present indicator, individually disconnect the machine harness from each of the following buffers one at a time:
PWM buffer for the left conveyor ratio dial.
PWM buffer for the right conveyor ratio dial.
PWM buffer for the left material height dial.
PWM buffer for the right material height dial.Expected Result:The diagnostic code present indicator turns OFF when one of the PWM buffers is removed from the machine harness.Results:
YES - The diagnostic code present indicator does turn OFF when one of the PWM buffers is removed from the machine harness.Repair: The circuit is correct. The machine harness and the ECM are operating properly. One of the PWM buffers is malfunctioning. Replace the appropriate PWM buffer. Stop.
NOT OK - The diagnostic code present indicator does not turn OFF when the PWM sensors have been disconnected from the machine harness.Repair: The machine harness or the ECM may be malfunctioning. Proceed to Test Step 2.Test Step 2. Check +V Circuit For Short to ReturnThe machine harness remains disconnected from all of the PWM buffers.
Turn the key start switch to the OFF position.
Disconnect the machine harness connector from the ECM.
At the machine harness connector for the ECM, measure the resistance from circuit at connector contact 40 (P128-BU) to connector contact 39 (P201-GN).Expected Result:The resistance should measure greater than 5000 ohms.Results:
OK - The resistance measurement is greater than 5000 ohms. Proceed to Test Step 3.
NOT OK - The resistance measurement is less than 5000 ohms.Repair: There is a short in the machine harness for the sensor supply circuit. The short is between the +V circuit (wire P128-BU) or the return circuit (wire P201-GN) of the machine harness. Repair the machine harness or replace the machine harness. Stop.Test Step 3. Check +V Circuit For Short to GroundThe key start switch remains OFF. The PWM buffers and the ECM remain disconnected from the