HARNESS ASSEMBLY-FRONT FRAME 2730275 - Caterpillar

Illustration 1 g00840478
Schematic of the Position sensor (swashplate angle)This diagnostic code is associated with the Position sensor (swashplate angle). The FMI 04 means that the ECM has determined that the voltage of the circuit for the position sensor is below normal. The input voltage of 0.25 DCV to 4.75 DCV from the sensor corresponds to a swashplate angle of -45 degrees to 45 degrees. The ECM recognizes a swashplate angle in the range of -5 degrees to 40 degrees as a valid swashplate angle. If the angle is less than -5 degrees, the ECM determines that the value is below the normal operational range. If the angle is greater than 40 degrees, the ECM determines that the value is above the normal operational range.The possible causes of this diagnostic code are listed below:
The signal circuit for the sensor is shorted to ground.
The sensor has failed.
The ECM has failed. This is unlikely. Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 1618 FMI 04 is active before performing this procedure. Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.System Response:When this diagnostic code is active, the Machine ECM will disable the AESC. The AESC will never be activated. Also, the Machine ECM will disable the Solenoid (High Pressure). High Pressure will never be provided to the stabilizer system. The Electronic Technician will display "Abnormal/Incorrect Data" parameter for the Main Pump Swashplate Angle.Test Step 1. CHECK THE SENSOR.
Turn the disconnect switch and the key start switch to the ON position.
Ensure that the diagnostic code is active.
Observe the status of the diagnostic code. Disconnect the sensor from the machine harness.Expected Result:The CID 1618 FMI 04 remains active. The FMI has not changed and the "04" is still active.Results:
OK - The diagnostic code remains active. The sensor is correct. Proceed to Test Step 2.
NOT OK - The diagnostic code is no longer active. The sensor has failed.Repair: Replace the sensor. Stop.Test Step 2. CHECK THE WIRING HARNESS OF THE SENSOR FOR A SHORT TO GROUND.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness from the sensor.
Disconnect the machine harness connector(s) from the ECM.
At the machine harness connector for the ECM, measure the resistance from the signal contact J1-62 (wire F475-GN) of the machine harness to all possible sources of ground. Measure the resistance to all contacts of the machine harness connectors for the ECM.Expected Result:Each resistance measurement is greater than 5000 ohms.Results:
OK - Each resistance measurement is greater than 5000 ohms. The machine harness is correct. Proceed to Test Step 3.
NOT OK - One or more resistance measurements is not correct. There is a short in the machine harness. Repair: The short is between signal contact J1-62 (wire F475-GN) and the circuit with the low resistance measurement. Repair the machine harness or replace the machine harness. Stop.Test