BODY 1151955 - Caterpillar

Illustration 1 g02408297
Machine ECM, 8 VDC Sensor Power Supply connectionsThis diagnostic code is associated with the Machine ECM, 8 VDC sensor power supply. The 8 VDC sensor power supply provides power for three pressure sensors on the machine. The three pressure sensors are:
The "Brake System" pressure sensor.
The "Boom Cylinder Head End" pressure sensor.
The "Boom Cylinder Rod End" pressure sensor.The CID 0041 FMI 04 diagnostic code is activated when the ECM detects that the voltage of the power supply circuit is lower than normal.The following conditions could cause this diagnostic code:
A sensor has failed.
The power supply circuit is shorted to a ground source.
The Machine ECM has failed. A failure of the ECM is unlikely.Note: The following test procedure may create other diagnostic codes. Clear the diagnostic codes when the problem has been corrected. Verify that the CID 0041 FMI 04 is active before performing this procedure.Test Step 1. CHECK THE SENSOR
Turn the key switch and the disconnect switch to the ON position.
Disconnect the hydraulic oil temperature sensor from the machine harness.
After disconnecting the sensor, check the status of the CID 0041 FMI 04 diagnostic code.Expected Result:The CID 0041 FMI 04 diagnostic code is no longer active.Results:
OK - The CID 0041 FMI 04 diagnostic code is not active when the sensor is disconnected. The harness circuit is correct. The sensor that was disconnected has failed.Repair: Replace the sensor.STOP
NOT OK - The CID 0041 FMI 04 diagnostic code is still active. The machine harness may be shorted to a ground source. Proceed to Test Step 2.Test Step 2. CHECK FOR A SHORT TO GROUND
Turn the key switch and the disconnect switch to the OFF position.
Disconnect the machine harness connectors J1 and J2 from the Machine ECM.
At the harness connector for the ECM, measure the resistance between supply contact J1-44 (wire E774-GN) and frame ground. Measure the resistance between supply contact J1-44 and all of the other contacts that are used in the J1 and J2 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 circuit in the machine harness is correct. Proceed to Test Step 3.
NOT OK - One or more of the resistance measurements is less than 5000 ohms. The circuit is shorted in the machine harness.Repair: The power supply wire E774-GN is shorted in the machine harness to frame ground or to the circuit with the low resistance measurement. Refer to the complete Electrical System Schematic for your machine. Check all harness connectors that are in the power supply circuit. Ensure that the connectors are clean and secure.Refer to the complete machine Electrical System Schematic. Examine all of the connectors in the circuits for points in the machine harness where the circuits could be shorted. For information on testing for short circuits and finding short circuits, refer to Testing and Adjusting, "Wiring Harness (Short Circuit) - Test". Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK THE STATUS OF THE DIAGNOSTIC CODE
Inspect the