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Diagnostic Test

  1. EXHAUST LEAK 
    NOTE: A thorough exhaust leak test must be completed before removing an O2 Sensor or any other part from the exhaust system. Do not remove any parts before an exhaust leak check has been completed.
    NOTE: An exhaust leak may cause downstream fuel adaptive to reach limits, resulting in a false 1/2 Oxygen Sensor failure

    Perform the diagnostic procedure for *CHECKING THE EXHAUST SYSTEM FOR LEAKS .

    Were any problems found? 

    Yes 

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

    No 

    1. Go to  2.
  2. DTC IS ACTIVE 
    NOTE: Check for contaminants that may have damaged the O2 Sensor: contaminated fuel, unapproved silicone, oil and coolant.
    NOTE: It may be necessary to test drive the vehicle within the DTC monitoring conditions in order for this DTC to set.

    Start the engine and allow it to reach 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.

    With a scan tool, select View DTCs.

    Is the status Active for this DTC? 

    Yes 

    1. Go to  3.

    No 

    1. Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.
  3. (K141) O2 1/2 SIGNAL CIRCUIT SHORTED TO VOLTAGE 
    Fig 1: Checking O2 Sensor Circuit
    GC0049470Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the 1/2 Oxygen Sensor harness connector.

    Turn the ignition on.

    Measure the voltage on the (K141) O2 1/2 Signal circuit in the 1/2 Oxygen Sensor harness connector.

    NOTE: Measure the voltage in reference to battery or chassis ground, not the (K904) O2 1/2 Return circuit.

    Is the voltage above 5.2 volts? 

    Yes 

    1. Repair the (K141) O2 1/2 Signal circuit for a short to voltage.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  4.
  4. (K904) O2 1/2 RETURN CIRCUIT SHORTED TO VOLTAGE 
    Fig 2: Checking O2 Sensor Circuit
    GC0049466Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Powertrain Control Module (PCM) harness connector.

    Turn the ignition on.

    Measure the voltage on the (K904) O2 1/2 Return circuit in the 1/2 Oxygen Sensor harness connector.

    Is there any voltage present? 

    Yes 

    1. Repair the (K904) O2 1/2 Return circuit for a short to voltage.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  5.
  5. (K141) O2 1/2 SIGNAL CIRCUIT SHORTED TO GROUND 
    Fig 3: Checking O2 Sensor Circuit
    GC0049468Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Measure the resistance between ground and the (K141) O2 1/2 Signal circuit in the 1/2 Oxygen Sensor harness connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the (K141) O2 1/2 Signal circuit for a short to ground.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  6.
  6. (K904) O2 1/2 RETURN CIRCUIT SHORTED TO GROUND 
    Fig 4: Checking O2 Sensor Circuit
    GC0049467Courtesy of CHRYSLER LLC

    Measure the resistance between ground and the (K904) O2 1/2 Return circuit in the 1/2 Oxygen Sensor harness connector.

    Is the resistance below 100 ohms? 

    Yes 

    1. Repair the (K904) O2 1/2 Return circuit for a short to ground.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  7.
  7. (K141) O2 1/2 SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 5: Checking O2 Sensor Circuit
    GC0049475Courtesy 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 (K141) O2 1/2 Signal circuit between the 1/2 Oxygen Sensor harness connector and the appropriate terminal of special tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  8.

    No 

    1. Repair the (K141) O2 1/2 Signal circuit for an open circuit or high resistance.
    2. Perform PCM VERIFICATION TEST .
  8. (K904) O2 1/2 RETURN CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 6: Checking O2 Sensor Circuit
    GC0049476Courtesy 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 (K904) O2 1/2 Return circuit between the 1/2 Oxygen Sensor harness connector and the appropriate terminal of special tool #8815.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  9.

    No 

    1. Repair the (K904) O2 1/2 Return circuit for an open circuit or high resistance.
    2. Perform PCM VERIFICATION TEST .
  9. 1/2 OXYGEN SENSOR 
    NOTE: Prior to replacing the O2 sensor, verify that the correct part number is being used in order to prevent improper O2 heater control.

    Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the 1/2 Oxygen 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 related connectors.

    Refer to any Technical Service Bulletins that may apply.

    Were any problems found? 

    Yes 

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

    No 

    1. Replace the 1/2 Oxygen Sensor in accordance with the Service Information.
    2. Perform PCM VERIFICATION TEST .
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