FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P1239






P1239-ENGINE OIL TEMPERATURE TOO LOW

For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
The engine oil temperature has dropped below a calibrated temperature value. Engine start up.

- Set Condition:
The Engine Oil temperature rises slower than a calibrated modeled temperature. When the actual oil temperature falls below the low boundary of the calibrated modeled temperature for three minutes the fault is set. Two trip fault. Three good trips to turn off the MIL.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. DTC IS ACTIVE

NOTE: Diagnose any CAN C Communication DTCs before continuing.

1. Turn the ignition off.
2. If possible, allow the vehicle to sit with the ignition off for more than 60 minutes in an environment where the temperature will allow the oil temperature to cool down.
3. Start the engine and allow it to reach normal operating conditions.
4. With the scan tool, select View DTCs.

Is the status Active or Pending for this DTC?

Yes

- Go To 2

No

- Perform the INTERMITTENT CONDITION diagnostic procedure. Intermittent Condition Test.

2. ENGINE OIL
The following conditions must be checked:

- OEM recommended oil viscosity is being used.
- Customer is following the oil change schedule.
- Check the engine oil for contamination. (i.e., fuel and/or engine coolant).
- Internal engine condition that may effect oil pressure.

Were any of the above conditions found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 3

3. ENGINE OIL TEMPERATURE SENSOR VOLTAGE
1. Turn the ignition off.
2. Disconnect the Engine Oil Temperature Sensor harness connector.
3. Turn the ignition on.
4. With the scan tool, read the Engine Oil Temperature Sensor voltage.

NOTE: The sensor voltage should be approximately 5.0 Volts (plus or minus.1 Volt) with the connector disconnected.

Does the scan tool display the voltage as described above?

Yes

- Go To 4

No

- Go To 5

4. ENGINE OIL TEMPERATURE SENSOR




1. Turn the ignition off.
2. Connect a jumper wire between the (G24) EOT Signal circuit and the (K900) Sensor Ground circuit in the Engine Oil Temperature Sensor harness connector.
3. Turn the ignition on.
4. With the scan tool, read the Engine Oil Temperature Sensor voltage.

NOTE: The sensor voltage should be approximately 0.0 Volts (plus or minus.1 Volt) with the jumper wire in place.

Does the scan tool display the voltage as described above?

Yes

- Replace the Engine Oil Temperature Sensor.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

No

- Go To 5

5. (G24) EOT SIGNAL CIRCUIT HIGH RESISTANCE




1. Turn the ignition off.
2. Disconnect the PCM C2 harness connector.
3. Measure the resistance of the (G24) EOT Signal circuit between the Engine Oil Temperature Sensor harness connector and the PCM C2 harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 6

No

- Repair the (G24) EOT Signal circuit for high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

6. (K900) SENSOR GROUND CIRCUIT HIGH RESISTANCE




1. Measure the resistance of the (K900) Sensor Ground circuit between the Engine Oil Temperature Sensor harness connector and the PCM C2 harness connector.

Is the resistance below 5.0 Ohms?

Yes

- Go To 7

No

- Repair the (K900) Sensor Ground circuit for high resistance.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.

7. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Engine Oil Temperature Sensor and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
5. Look for the data to change or for the DTC to reset during the wiggle test.
6. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Replace and program the Powertrain Control Module. Powertrain Control Module - Removal.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test.