 | |
| Illustration 1 | g02305953 |
Schematic of the transfer case sump oil temperature sender | |
This diagnostic trouble code is associated with the transfer case sump oil temperature sender. The FMI 16 means that the ECU has determined that the oil temperature is above a normal operational range. The temperature could cause severe damage. The ECU reads the resistance from the sensor. A high oil temperature will send a low voltage to the ECU. The high temperature sends a voltage that is lower than the expected result for the ECU.
The cause of this diagnostic trouble code is listed:
- The oil temperature has reached 121° ± 8°C (250° ± 14°F).
The possible causes of this diagnostic trouble code are listed:
- Excessive oil temperature
System Response:
The vehicle is safe when the temperature of the oil is below 121 °C (250 °F). Oil at this temperature is in the green area on the gauge. Operators should modify the operation of the vehicle in order to reduce the temperature of the oil as soon as possible when the temperature is between 121 °C (250 °F) and 149 °C (300 °F). Oil at this temperature is in the yellow area on the gauge. Operating a vehicle can result in damage to the transmission when the temperature of the oil is above 149 °C (300 °F). Oil at this temperature is in the red area on the gauge.
Test Step 1. INSPECT THE HARNESS CONNECTIONS.
- Turn the disconnect switch to the OFF position.
- Check the connectors for proper mating.
- Check the wires at the connector.
- Check each wire for nicks or signs of abrasion in the insulation.
- Check for moisture at the connector.
- Check the connectors for dirty contacts or corroded contacts.
- Check each pin and each socket of the machine harness connectors.
Expected Result:
The machine harness connectors are tight and free of corrosion.
Results:
- OK - The machine harness connectors are tight and free of corrosion. Proceed to test step 2.
- NOT OK - The machine harness connectors are in need of repair.
Repair: Repair the machine harness or replace the machine harness.
STOP
Test Step 2. VERIFY THE TEMPERATURE OF THE OIL.
Check the temperature of the oil.
Results:
- OK - The temperature of the oil is correct. Proceed to Test Step 3.
- NOT OK - The temperature of the oil is not correct.
Repair: Stop the engine until the oil temperature returns to an acceptable range.
STOP
Test Step 3. CHECK IF THE DIAGNOSTIC TROUBLE CODE REMAINS.
- Inspect the harness connectors. Clean the contacts of the harness connectors and check the wires for damage to the insulation that is caused by excessive heat, battery acid, 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. Make sure that the harness connectors are fully seated and that the clips for each connector are fastened.
- Turn the disconnect switch and the key start switch to the ON position.
- Operate the vehicle.
- Check the status of the SPN 441 FMI 16.
Expected Result:
The SPN 441 FMI 16 is active.
Results:
- YES - The SPN 441 FMI 16 is active. The diagnostic trouble code has not been corrected.
Repair: Check the circuit again. It is unlikely that the ECU has failed. Exit this procedure and perform this procedure again. If the cause of the diagnostic trouble code is not found, replace the ECU. Prior to replacing an ECU, always contact your dealership for possible consultation with Caterpillar. This consultation may greatly reduce repair time. See Testing and Adjusting, "Electronic Control Unit - Replace".
STOP
- NO - The SPN 441 FMI 16 is not active. The diagnostic trouble code does not exist at this time. The initial diagnostic trouble code was probably caused by a poor electrical connection at one of the harness connectors that was disconnected and reconnected. Resume normal vehicle operation.STOP