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Diagnostic Test

  1. 1/2 OXYGEN SENSOR VOLTAGE 
    NOTE: If an O2 sensor signal circuit is shorted to voltage, all O2 sensor voltage readings displayed on the scan tool will be approximately 5.0 volts. Diagnose the sensor that set the most current DTC.

    Start the engine and allow it to idle for at least 60 seconds.

    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  2.

    No 

    1. Refer to the *CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure.
  2. (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.

    Disconnect the Powertrain Control Module (PCM) harness connector.

    Turn the ignition on.

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

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

    Is there any voltage present? 

    Yes 

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

    No 

    1. Go to  3.
  3. (K904) O2 1/2 RETURN CIRCUIT SHORTED TO VOLTAGE 
    Fig 2: Checking O2 Sensor Circuit
    GC0049466Courtesy of CHRYSLER LLC

    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  4.
  4. (K141) O2 1/2 SIGNAL CIRCUIT SHORTED TO THE (K299) O2 1/2 HEATER CONTROL CIRCUIT 
    Fig 3: Measuring The Resistance Between The O2 1/1 Signal Circuit And The O2 1/1 Heater Control Circuit The 1/1 O2 Sensor Harness Connector
    GC0049471Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Measure the resistance between the (K141) O2 1/2 Signal circuit and the (K299) O2 1/2 Heater Control circuit the 1/2 Oxygen Sensor harness connector.

    Is the resistance below 100.0 ohms? 

    Yes 

    1. Repair the (K141) O2 1/2 Signal circuit for a short to the (K299) O2 1/2 Heater Control circuit.
    2. Perform PCM VERIFICATION TEST .

    No 

    1. Go to  5.
  5. 1/2 OXYGEN SENSOR VOLTAGE 
    Fig 4: Checking O2 Sensor Circuit
    GC0049472Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Connect the Powertrain Control Module (PCM) harness connector.

    Connect a jumper wire between the (K141) O2 1/2 Signal circuit and the (K904) O2 1/2 Return circuit in the 1/2 Oxygen Sensor harness connector.

    Turn the ignition on.

    With a scan tool, monitor the 1/2 Oxygen Sensor Volts.

    Is the voltage between 2.3 and 2.7 volts with the jumper wire in place? 

    Yes 

    1. Go to  8.

    No 

    1. Go to  6.
  6. (K141) O2 1/2 SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 5: Checking O2 Sensor Circuit
    GC0049475Courtesy of CHRYSLER LLC

    Turn the ignition off.

    If necessary, remove the jumper wire from between the (K141) O2 1/2 Signal circuit and the (K904) O2 1/2 Return circuit in the 1/2 Oxygen Sensor harness connector.

    Disconnect the Powertrain Control Module (PCM) harness connector.

    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  7.

    No 

    1. Repair the (K141) O2 1/2 Signal circuit for an open circuit or high resistance.
    2. Perform PCM VERIFICATION TEST .
  7. (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 .
  8. 1/2 OXYGEN SENSOR 

    Turn the ignition off.

    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.

    Were any problems found? 

    Yes 

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

    No 

    1. Replace the 1/2 Oxygen Sensor.
    2. Perform PCM VERIFICATION TEST .
  9. POWERTRAIN CONTROL MODULE (PCM) 

    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 and program the Powertrain Control Module (PCM) in accordance with the Service Information.
    2. Perform PCM VERIFICATION TEST .
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