GUIDE 1138299 - Caterpillar

Conditions Which Generate This Code:
Illustration 1 g02606279
Connections of the transmission oil temperature sensorNote: THE HARNESS BETWEEN THE ECM AND THE OEM CONNECTOR IS NOT A CATERPILLAR HARNESS. FOR MORE INFORMATION ABOUT THIS HARNESS PLEASE CONTACT THE OEM MANUFACTURER.This diagnostic code is associated with the transmission oil temperature sensor. The FMI 04 means that the ECM has determined that the voltage of the circuit for the position sensor is below normal. The possible causes of this diagnostic code are listed below:
The signal circuit for the sensor is shorted to ground.
The sensor has failed.
The ECM has failed. An ECM failure is unlikely. Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0177 FMI 04 is active before performing this procedure. Note: Use a digital multimeter for the measurements in this procedure.System Response:A warning of a level 1 is generated. Use the default value.Test Step 1. CHECK THE SENSOR
Turn the disconnect switch and the key start switch to the ON position.
Ensure that the diagnostic code is active.
Observe the status of the diagnostic code. Disconnect the sensor from the machine harness.Expected Result:The diagnostic code remains active. The diagnostic code has not changed and the "FMI 04" is still active.Results:
OK - The diagnostic code remains active. The sensor is correct. Proceed to Test Step 2.
NOT OK - The diagnostic code is no longer active. The sensor has failed.Repair: Replace the sensor.STOPTest Step 2. CHECK THE WIRING HARNESS OF THE SENSOR FOR A SHORT TO GROUND.
Turn the key start switch and the disconnect switch to the OFF position.
Disconnect the machine harness from the sensor.
Disconnect the machine harness connectors from the ECM.
At the machine harness connector for the ECM, measure the resistance from the signal contact J1-22 of the machine harness to all possible sources of ground. Measure the resistance to all contacts of 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 - One or more resistance measurements are not correct. There is a short in the machine harness. Repair: The short is between signal contact J1-22 and the circuit with the low resistance measurement. Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK IF THE DIAGNOSTIC CODE REMAINS.
Inspect the contacts of the harness connectors and clean the contacts.
Reconnect all harness connectors.
Turn the disconnect switch and the key start switch to the ON position.
Operate the machine.
Check the status of the diagnostic code.Expected Result:The diagnostic code is active.Results:
YES - The diagnostic code is active. The diagnostic code has not been corrected. The ECM may have failed.Repair: Exit this procedure and perform the diagnostic code procedure again. If the problem persists, the ECM may have failed. Prior to replacing an ECM, always contact your dealership for possible consultation with Caterpillar. This