IDLER GP-FRONT 4220861 - Caterpillar

Illustration 1 g03429144
Illustration of the electrical connections of the "Starter Motor Relay"
This diagnostic code is associated with the "Starter Motor Relay". The FMI 03 diagnostic code means that the ECM has determined that the voltage of the relay circuit is above normal.The possible causes of the diagnostic code are listed:
The relay has failed.
The power circuit of the relay is shorted to the +battery circuit.
The Machine ECM has failed. This situation is unlikely.Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all of the connections in the circuit are clean and secure. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure.Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear these diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0444 FMI 03 is active before performing this procedure.Note: Use a digital multimeter for the measurements in this procedure.Test Step 1. CHECK THE RELAY
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness connectors J1 and J2 from the ECM.
At the J1 and J2 harness connector, measure the resistance between contact J2-8 (wire C903-BU(Blue)) and contact J1-2/J1-14 (wire 235-BK(Black)).Expected Result:The resistance of the relay coil should measure 27.3 3 ohms at 20 °C (68.0 °F). Some deviation due to temperature is acceptable.Results:
OK - The resistance measurement of the relay coil is within the acceptable range. Proceed to Test Step 2.
NOT OK - The resistance measurement of the relay coil is NOT within the acceptable range.Repair: The relay has failed. Replace the relay.STOPTest Step 2. CHECK THE POWER CIRCUIT OF THE RELAY FOR A SHORT TO THE +BATTERY CIRCUIT
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness connectors from the ECM. Disconnect the machine harness connector from the start relay.
At the machine harness connector for the ECM, measure the resistance from contact J2-8 (wire C903-BU(Blue)) to all contacts that are used in 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 - Each resistance measurement is not greater than 5000 ohms. There is a short in the machine harness. The short is between J2-8 (wire C903-BU(Blue)) and the circuit that has a low resistance measurement.Repair: Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK THE STATUS OF THE DIAGNOSTIC CODE
Inspect the contacts and clean the contacts of the harness connectors.
Reconnect all harness connectors.
Turn the disconnect switch and the key start switch to the ON position.
Operate the machine.
Determine if the diagnostic code is active.Expected Result:The diagnostic code is active.Results:
YES - The diagnostic code is active. The problem has