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| Illustration 1 | g02729643 |
Connections for the Torque Converter Temperature Sensor | |
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| Illustration 2 | g01896773 |
Location of the torque converter temperature sensor | |
This sensor is connected to the Implement ECM. The Implement ECM sends the diagnostic information to the Machine ECM via the CAN data link. This diagnostic code is associated with the torque converter temperature sensor. The FMI 04 means that the ECM has determined that the voltage of the circuit for the 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. 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 0826 FMI 04 is active before performing this procedure.
Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.
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 machine harness from the sensor.
Expected Result:
The CID 0826 FMI 04 remains active. The FMI has not changed and the "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- NOT OK - The diagnostic code is no longer active.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.
STOP
Test 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 39 (wire 443-YL) 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 measurement is not correct. There is a short in the machine harness.
Repair: The short is between signal contact 39 (wire 443-YL) and the circuit with the low resistance measurement. Repair the machine harness or replace the machine harness.
STOP
Test Step 3. CHECK THE STATUS OF THE DIAGNOSTIC CODE
- Inspect the harness connectors and clean the contacts of the harness connectors. Check the wires for damage to the insulation that is caused by excessive heat, corrosion, or chafing.
- Perform a 45 N (10 lb) pull test on each of the wires that are associated with the circuit.
- Reconnect all harness connectors. Ensure that the connectors are fully seated. Ensure that the clips for each of the connectors are fastened.
- Turn the disconnect switch and the key start switch to the ON position.
- Operate the machine.
- Check the status of the CID 0826 FMI 04.
Expected Result:
The CID 0826 FMI 04 is active.
Results:
- YES - The CID 0826 FMI 04 is active. The diagnostic code has not been corrected. The ECM may have failed.
Repair: If the problem has not been corrected, use Caterpillar Electronic Technician (ET) in order to perform a wiggle test on the sensor circuit in the machine wiring harness. The wiggle test can detect intermittent shorts or opens in the machine wiring harness.If the problem is still present, replace the temperature sensor. After the sensor is replaced, perform this test step again. If the problem is still present, the ECM may be faulty.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 Technical Communicator for possible consultation with Caterpillar. This consultation may greatly reduce repair time. If the cause of the diagnostic code is not found, replace the ECM. See the Troubleshooting, "Electronic Control Module (ECM) - Replace".
STOP
- NO - The CID 0826 FMI 03 is not active. The diagnostic code does not exist at this time.
Repair: The initial diagnostic code was probably caused by a poor electrical connection at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation.
STOP