GRILL 3454140 - Caterpillar

Illustration 1 g01079534
Schematic for the 5 V supplyCID 262 FMI 03 service code is recorded when the ECM reads the voltage of the sensor supply circuit (wire L730-OR) as higher than the normal voltage.The following causes could signal this diagnostic code:
The sensor supply circuit (wire L730-OR) is shorted to the +battery circuit.
A sensor has failed.
The ECM has failed. This is unlikely.Note: Ensure that the CID 262 FMI 03 is active.System Response:When this diagnostic code is active the hydraulic control system will default to the "Auto Not Allowed" state.Test Step 1. CHECK FOR THE CORRECT VOLTAGE AT THE ECM.
Turn the disconnect switch and the key start switch to the ON position.
Check the voltage at the connector of the ECM from contact J1-11 (sensor supply) to contact J1-21 (ground). Use the 7X-1710 Cable probes to measure the voltage. Do NOT disconnect the machine harness from the ECM.Expected Result:The voltage is 5.0 0.5 DCV.Results:
OK - Voltage is 5.0 0.5 DCV. The sensor supply voltage is correct. Verify that the diagnostic code is present. If the diagnostic code is still present, the ECM has failed. Replace the ECM.Repair: It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code is active. If the cause of the diagnostic code is not found, replace the ECM. See Testing and Adjusting, "Module - Replace".STOP
NOT OK - Voltage is greater than 5.0 0.5 DCV. The sensor supply voltage is NOT correct. Proceed to test step 2.Test Step 2. CHECK THE HARNESS FOR A SHORT TO THE +BATTERY CIRCUIT.
The disconnect switch and the key start switch remain in the ON position.
Disconnect the machine harness from the ECM.
At the machine harness connector for the ECM, measure the voltage from connector contact J1-11 (sensor supply) to frame ground.Expected Result:The voltage is 0.0 0.5 DCV.Results:
OK - The voltage is 0.0 0.5 DCV. The voltage is correct. The ECM has failed.Repair: It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. Also, recheck if the diagnostic code is active. If the cause of the diagnostic code is not found, replace the ECM. See Testing and Adjusting, "Module - Replace".STOP
NOT OK - Voltage is NOT 0.0 0.5 DCV. The harness has failed.Repair: The machine harness is shorted to the +battery circuit. Repair the machine harness or replace the machine harness.STOP