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Diagnostic Test

  1. DTC IS ACTIVE 
    1. 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 may result in possible serious or fatal injury.
    2. With the scan tool, select View DTCs.

      Is the status Active for this DTC?

      Yes 

      • Go to step  2

      No 

  2. (Z931) GROUND CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 1: Checking Ground Circuit
    GC0123810Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the Oxygen Sensor 1/2 harness connector.
    3. Turn the ignition on.
    4. Using a 12-volt test light connected to 12 volts, check the (Z931) 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 

      • Go to step  3

      No 

  3. (K299) O2 1/2 HEATER CONTROL CIRCUIT SHORTED TO GROUND 
    Fig 2: Checking O2 Heater Control Circuit
    GC0123811Courtesy of CHRYSLER LLC
    1. Turn the ignition off.
    2. Disconnect the Powertrain Control Module (PCM) harness connector.
    3. 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 

      No 

      • Go to step  4
  4. (K299) O2 1/2 HEATER CONTROL CIRCUIT OPEN OR HIGH RESISTANCE 
    Fig 3: Checking O2 Heater Control Circuit
    GC0123815Courtesy of CHRYSLER LLC
    NOTE: When checking circuits at the Powertrain Control Module (PCM), be careful not to damage or distort the connector terminals. Improper measurement technique could result in poor pin to terminal contact.
    1. 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 

      • Go to step  5

      No 

  5. OXYGEN SENSOR 1/2 HEATER CONTROL ACTUATOR 
    Fig 4: Checking O2 Heater Control Circuit
    GC0123813Courtesy of CHRYSLER LLC
    1. Connect the Powertrain Control Module (PCM) harness connector.
    2. Turn the ignition on.
    3. With the scan tool, actuate the Oxygen Sensor 1/2 control to the ON (100%) position.
    4. 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.
    5. With the scan tool, actuate the Oxygen Sensor 1/2 control to OFF (0%).
    6. 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 

      • Go to step  6

      No 

      • Go to step  7
  6. OXYGEN SENSOR 1/2 
    1. Turn the ignition off.
    2. Inspect the wiring and connectors between the Oxygen Sensor 1/2 and the Powertrain Control Module (PCM).
    3. Look for any chafed, pierced, pinched, or partially broken wires.
    4. 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 

      No 

  7. POWERTRAIN CONTROL MODULE (PCM) 
    1. 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).
    2. Look for any chafed, pierced, pinched, or partially broken wires.
    3. Look for broken, bent, pushed out or corroded terminals.
    4. Perform any Technical Service Bulletins that may apply.

      Were any problems found?

      Yes 

      No