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Diagnostic Test

  1. 1) DTC IS ACTIVE 

    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.

    With the 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 CONDITION Diagnostic Procedure.
  2. 2) (Z924) GROUND CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 1: Checking (Z924) Ground Circuit In Oxygen Sensor 1/2 Harness Connector
    GC0053969Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Oxygen Sensor 1/2 connector.

    Turn the ignition on.

    Using a 12 volt test light connected to 12 volts, check the (Z924) Ground circuit in the Oxygen Sensor 1/2 harness connector.

    NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

    Is the test light illuminated and bright? 

    Yes 

    1. Go to  3).

    No 

    1. Repair the (Z924) Ground circuit for an open circuit or high resistance.
    2. Perform PCM VERIFICATION TEST .
  3. 3) (K299) O2 1/2 HEATER CONTROL CIRCUIT SHORTED TO GROUND 
    Fig 2: Checking O2 Sensor 1/2 Heater Control Circuit For Short To Ground
    GC0053970Courtesy of CHRYSLER LLC

    Turn the ignition off.

    Disconnect the Powertrain Control Module (PCM) connector.

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

    Is the resistance below 100 ohms? 

    Yes 

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

    No 

    1. Go to  4).
  4. 4) (K299) O2 1/2 HEATER CONTROL CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 3: Checking O2 Sensor 1/2 Heater Control Circuit For Open Or High Resistance
    GC0053971Courtesy of CHRYSLER LLC

    Measure the resistance of the (K299) O2 1/2 Heater Control circuit between the Oxygen Sensor 1/2 harness connector and the Powertrain Control Module (PCM) harness connector.

    Is the resistance below 5.0 ohms? 

    Yes 

    1. Go to  5).

    No 

    1. Repair the (K299) O2 1/2 Heater Control circuit for an open circuit or high resistance.
    2. Perform PCM VERIFICATION TEST .
  5. 5) OXYGEN SENSOR 1/2 
    Fig 4: Checking (K299) O2 1/2 Heater Control Circuit In Oxygen Sensor 1/2 Harness Connector
    GC0053972Courtesy of CHRYSLER LLC

    Connect the Powertrain Control Module (PCM) connector.

    Turn the ignition on.

    With the scan tool, actuate the Oxygen Sensor 1/2 control to the ON (100%) position.

    Using a 12 volt test light connected to ground, check the (K299) O2 1/2 Heater Control circuit in the Oxygen Sensor 1/2 harness connector.

    NOTE: The test light should be illuminated and bright with the control actuated ON (100%). Compare the brightness to that of a direct connection to the battery.

    With the scan tool, actuate the Oxygen Sensor 1/2 control to OFF (0%).

    Using a 12 volt test light connected to ground, check the (K299) O2 1/2 Heater Control circuit in the Oxygen Sensor 1/2 harness connector.

    NOTE: The test light should not be illuminated with the control actuated OFF (0%).

    Is the test light illuminated and bright with the control actuated ON and not illuminated with the control actuated OFF? 

    Yes 

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

    No 

    1. Go to  6).
  6. 6) POWERTRAIN CONTROL MODULE (PCM) 

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

    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 .