COVER 3T2051 - Caterpillar

Transmission, SPN 734 FMI 3Conditions Which Generate This Code:
Illustration 1 g01335041
Connections of the transmission clutch solenoid 1
This diagnostic code is associated with the transmission clutch solenoid 1. The FMI 3 means that the ECM has determined that the voltage of the solenoid circuit is above normal.The possible causes of the diagnostic code are listed:
The solenoid has failed.
The energize circuit of the solenoid is shorted to the +battery circuit.
The ECM has failed. This is unlikely.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 SPN 734 FMI 3 is active before performing this procedure.Note: Use a digital multimeter for the measurements in this procedure.Test Step 1. CHECK THE ENERGIZE CIRCUIT OF THE SOLENOID 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 solenoid and the ECM.
At the machine harness connector for the ECM, measure the resistance from contact J2-4 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 2.
NOT OK - Each resistance measurement is not greater than 5000 ohms. There is a short in the machine harness. The short is between J2-4 and the circuit that has a low resistance measurement. Repair: Repair the machine harness or replace the machine harness.STOPTest Step 2. CHECK THE OPERATION OF THE ECM.The disconnect switch and the key start switch remain in the OFF position. The machine harness connectors for the solenoid and the ECM remain disconnected.
At the J2 connector for the ECM, use a wire removal tool to remove wire J838-OR(Orange) from contact J2-4.
Reconnect the machine harness J1 and J2 connectors to the ECM.
Turn the disconnect switch and the key start switch to the ON position.
Observe the status of the active diagnostic code. Expected Result:The FMI 3 changes to an FMI 5 after the wire is disconnected.Results:
YES - The FMI 3 changes to a FMI 5 after the wire is disconnected. The ECM has responded correctly to the condition of an open circuit. Reinstall the disconnected wire to the correct space in the ECM connector before proceeding to the next Test Step. Proceed to Test Step 3.
NO - The FMI 3 remains active. The status of the active diagnostic code did not change when the wire was disconnected from the ECM.Repair: The ECM has not responded correctly to the condition of an open circuit. The operation of the ECM is not correct. Prior to replacing an ECM, always contact your dealership for possible consultation with Caterpillar. This consultation may greatly reduce repair time. If the ECM requires replacing, refer to Testing and Adjusting, "Electronic Control Module (ECM) - Replace".STOPTest Step 3. CHECK IF THE DIAGNOSTIC CODE IS STILL ACTIVE.
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