854G and 854K Wheel Dozers and 992G, 992K and 994F Wheel Loaders VIMSTM MID 049 - CID 0826 - FMI 03 Caterpillar

Conditions Which Generate This Code:

Illustration 1	g06012806
Schematic of the Torque Converter Oil Temperature Sensor

This diagnostic code is associated with the Torque Converter Oil Temperature Sensor. This diagnostic code is recorded when the ECM reads the input signal from the Sensor and the voltage is above normal.

If the voltage of the sensor input circuit is greater than 4.95 VDC, an FMI 03 diagnostic code will be activated.

Possible causes of the diagnostic code are listed:

• The signal circuit is open or the sensor is disconnected.

• The return circuit is open.

• The signal circuit is shorted to another circuit.

• The sensor has failed.

• The ECM has failed. ECM failure is the least likely cause.

Poor connections may be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean. Verify that all connections in the circuit are secure. Verify that all connections in the circuit are in good condition. 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 the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0826 FMI 03 is active before performing this procedure.

Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.

Test Step 1. CHECK FOR AN OPEN IN THE RETURN CIRCUIT

1. Turn the key start switch and the disconnect switch to the OFF position.

2. Locate the sensor and disconnect the machine harness from the sensor.

3. At the machine harness connector for the sensor, place a jumper wire from contact 2 (wire J842-BK(Black)) to frame ground.

   Note: Ensure that the frame ground contact point is clean and free of paint, oil, dirt, and any other debris.

4. Disconnect the machine harness connector J2 from the ECM.

5. At the J2 machine harness connector for the ECM, measure the resistance from contact J2-19 (wire J842-BK(Black)) to frame ground.

   Note: Ensure that the frame ground contact point is clean and free of paint, oil, dirt, and any other debris.

Expected Result:

The resistance measurement is less than 5 ohms.

Results:

• OK - The resistance measurement is less than 5 ohms. Proceed to test step 2.

• NOT OK - The resistance measurement is greater than 5 ohms. There is an open in the machine harness in the sensor return circuit (wire J842-BK(Black)).

  Repair: Repair the harness or replace the harness.

  STOP

Test Step 2. CHECK FOR AN OPEN IN THE SIGNAL CIRCUIT

1. The key start switch and the disconnect switch remain in the OFF position.

2. The J2 ECM connector remains disconnected.

3. At the machine harness connector for the sensor, remove the end of the jumper wire, installed in the previous step, from frame ground. Install that end of the jumper wire to contact 1 (wire 443-YL(Yellow)) of the machine harness connector for the sensor.

4. At the J2 ECM machine harness connector, measure the resistance from contact J2-44 (wire 443-YL(Yellow)) to contact J2-19 (wire J842-BK(Black)).

Expected Result:

The resistance measurement is less than 5 ohms.

Results:

• OK - The resistance measures less than 5 ohms. Proceed to test step 3.

• NOT OK - The resistance measurement is greater than 5 ohms. There is an open in the machine harness somewhere between the ECM and sensor in the sensor supply circuit (wire 443-YL(Yellow)).

  Repair: Repair the harness or replace the harness.

  STOP

Test Step 3. CHECK THE SIGNAL CIRCUIT FOR A SHORT

1. The disconnect switch and the key start switch remain in the OFF position.

2. The J1 ECM connector remains disconnected.

3. Disconnect the J2 machine harness connector from the ECM.

4. Remove the jumper wire that was installed for the previous step at the machine harness connector for the sensor between contacts 1 and 2.

5. At the J1 and J2 machine harness connectors for the ECM, measure the resistance of the sensor signal circuit at contact J1-30 (wire 443-YL(Yellow)) to all other J1 and J2 contacts.

Expected Result:

Each resistance measurement should be greater than 5000 ohms.

Results:

• OK - Each resistance measurement is greater than 5000 ohms. The sensor may have failed.

  Repair: Replace the sensor.Verify that the new sensor corrected the problem. If the problem persists, The ECM may have failed.The failed condition of the ECM is unlikely. Recheck the status of the diagnostic code. If the diagnostic code remains present, exit this procedure and perform this procedure again. Contact the Technical Communicator for your dealership for possible consultation with AVSpare prior to replacing the ECM. This consultation may greatly reduce repair time. If the ECM requires replacement, refer to Troubleshooting, "Electronic Control Module (ECM) - Replace".

  STOP

• NOT OK - Any resistance measurement less than 5000 ohms. There is a short in the machine harness somewhere between the sensor signal circuit wire (443-YL(Yellow)) and the circuit with the low-resistance measurement.

  Repair: Repair the harness or replace the harness.

  STOP