HARNESS AS-PANEL 4892519 - Caterpillar

Illustration 1 g01365165
Schematic of the Electrical System power supply to the Implement (Screed) ECMThis diagnostic code is recorded when the Implement (Screed) ECM reads the electrical system voltage that is at contact J1-31 (wire 140-RD) as being below normal range (less than 18 volts for two seconds).Note: The Implement (Screed) ECM is located under the Screed Platform.The possible causes of this diagnostic code are listed:
A charging system component has failed.
The ECM has failed. This is unlikely.This diagnostic code causes the implements to be inoperative because the voltage is too low in order to energize the solenoids.Ensure that CID 0168 FMI F01 is on hold. The "SERV CODE" indicator on the Caterpillar Monitoring System is illuminated.System Response:When this diagnostic code is active, the following occurs:
Components connected to controller will not log faults.
Machine may become inoperable.Test Step 1. CHECK THE BATTERY VOLTAGE.
Measure the voltage at the battery posts.Expected Result:The voltage is greater than 18 VDC.Results:
YES - The voltage is greater than 18 DCV. This should not cause the diagnostic code. Proceed to test step 2.
NO - The voltage is less than 18 DCV. The charging system is not correct. Repair: Check the charging system. See Special Instruction, REHS0354, "Charging System Troubleshooting". STOPTest Step 2. CHECK THE SYSTEM VOLTAGE
Disconnect the machine harness from the ECM.
Turn the disconnect switch and the key start switch to the ON position.
At machine harness connector J1 for the ECM, measure the voltage between contact J1-31 (wire 140-RD) and contact J1-23 (wire 200-BK).Expected Result:The voltage measures battery voltage.Results:
YES - The voltage is greater 18 DCV. This should not cause the diagnostic code. Repair: Inspect connector J1. Connect the machine harness to the ECM. If the CID 0168 FMI F01 remains present, check the charging system. See Special Instruction, REHS0354, "Charging System Troubleshooting". If the cause of the diagnostic code is not found, the ECM may have failed. Exit this procedure and perform this entire procedure again. Prior to replacing an ECM, always contact your dealership's Technical Communicator for possible consultation with Caterpillar. This consultation may greatly reduce repair time. If the ECM requires replacement, refer to Troubleshooting, "Electronic Control Module (ECM) - Replace".STOP
NO - The voltage is less than 18 DCV. The machine harness has failed. Repair: Check the +battery circuit and the ground circuit in the machine harness. Repair the machine harness or replace the machine harness. STOP