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Diagnostic Test

  1. ACTIVE DTC 

    Start the engine and allow it to reach normal operating temperature.

    WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.
    NOTE: Diagnose and repair any system voltage DTCs before continuing with this test.

    With the scan tool, select View DTCs.

    Is the DTC Active at this time? 

    Yes 

    1. Go To  2.

    No 

    1. Refer to the INTERMITTENT CONDITION Diagnostic Procedure.
  2. ENGINE OIL TEMPERATURE SENSOR 

    Turn the ignition off.

    Disconnect the Engine Oil Temp Sensor harness connector.

    Ignition on, engine not running.

    With a scan tool, read Engine Oil Temp 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 

    1. Verify that there is good pin to terminal contact in the EOT Sensor and Powertrain Control Module connectors. Replace the Engine Oil Temperature Sensor if no problems were found with the connectors.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To  3.
  3. (G224) ENGINE OIL TEMP SIGNAL CIRCUIT SHORTED TO THE (K900) SENSOR GROUND CIRCUIT 
    Fig 1: Checking EOT Sensor Signal Circuit For Short To Sensor Ground Circuit
    GC0069964Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the PCM harness connectors.

    Measure the resistance between the (K900) Sensor ground circuit and the (G224) Engine Oil Temp Signal circuit in the Engine Oil Temp Sensor harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Repair the short to between the (K900) Sensor ground circuit and the (G224) Engine Oil Temp Signal circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To  4.
  4. (G224) ENGINE OIL TEMP SIGNAL CIRCUIT SHORTED GROUND 
    Fig 2: Checking EOT Sensor Signal Circuit For Short To Ground
    GC0069965Courtesy of CHRYSLER LLC

    Measure the resistance between ground and the (G224) Engine Oil Temp Signal circuit in the Engine Oil Temp Sensor harness connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the short to ground in the (G224) Engine Oil Temp Signal circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Go To  5.
  5. (G224) EOT SIGNAL CIRCUIT OPEN CIRCUIT OR HIGH RESISTANCE 
    Fig 3: Checking EOT Sensor Signal Circuit For Open Or High Resistance
    GC0069961Courtesy of CHRYSLER LLC
    CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals, resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform diagnosis.

    Measure the resistance of the (G224) EOT Signal circuit between the Engine Oil Temperature Sensor harness connector and the appropriate terminal of special tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go To  6.

    No 

    1. Repair the excessive resistance in the (G224) EOT Signal circuit.
    2. Perform POWERTRAIN VERIFICATION TEST .
  6. POWERTRAIN CONTROL MODULE (PCM) 

    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).

    Look for any chafed, pierced, pinched, or partially broken wires.

    Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the Sensor and Control Module connectors.

    Refer to any Technical Service Bulletins that may apply.

    Were there any problems found? 

    Yes 

    1. Repair as necessary.
    2. Perform POWERTRAIN VERIFICATION TEST .

    No 

    1. Replace and program the Powertrain Control Module per Service Information.
    2. Perform POWERTRAIN VERIFICATION TEST .