BLOCK 5H9804 - Caterpillar

Illustration 1 g02042457
Schematic of the "Auxliary Pedal 1 Control Pressure" Sensor
This diagnostic code is associated with the "Auxiliary Pedal 1 Control Pressure" Sensor. This diagnostic code is recorded when the Machine ECM reads the sensor signal voltage and the voltage is too low. The possible causes of this failure are listed below:
The sensor has failed.
The signal circuit in the machine harness is shorted to ground.
The Machine ECM has failed. A failure of the ECM is unlikely.Test Step 1. CHECK THE SENSOR.
Disconnect the machine harness from the sensor. Expected Result:The diagnostic code changes from CID 3577 FMI 04 to a CID 3577 FMI 03 diagnostic code. Results:
OK - The diagnostic code changed to CID 3577 FMI 03. This change indicates that the failure is no longer present. The sensor has failed.Repair: Replace the sensor.STOP
NOT OK - The diagnostic code CID 3577 FMI 04 remained active. This change indicates that the failure remains present. The sensor is not the cause of the failure. Proceed to Test Step 2.Test Step 2. CHECK THE HARNESS.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the J1 machine harness connector from the Machine ECM.
At the harness connector for the sensor, measure the resistance between the signal contact 3 (wire N795-WH(White)) and frame ground. Expected Result:The resistance is greater than 5000 ohms. Results:
OK - The resistance is greater than 5000 ohms. The harness circuit resistance is correct. The Machine ECM may have failed. Repair: A failure of the Machine ECM is unlikely. Exit this procedure and perform this diagnostic code procedure again. If the failure is not found, replace the Machine ECM. See the Testing and Adjusting, "Electronic Control Module (ECM) - Replace" section of this manual. STOP
NOT OK - The resistance is less than 5000 ohms. The machine harness has failed. There is a short between frame ground and the signal circuit in the machine harness. Repair: Repair the machine harness or replace the machine harness. STOP