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Diagnostic Test

  1. DTC IS ACTIVE 
    1. Turn the ignition on.
    2. With a scan tool, select View DTCs. Record DTC and Freeze Frame information.
    3. 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 hand near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in possible serious or fatal injury.
    4. With a scan tool, select View DTCs.

      Is the status Active for this DTC?

      Yes 

      • Go to step  2

      No 

  2. (K43) O2 2/1 SIGNAL CIRCUIT 
    1. Turn the ignition off.
    2. Disconnect the 2/1 Oxygen Sensor harness connector.
    3. Turn the ignition on.
    4. With a scan tool, read the 2/1 Oxygen Sensor voltage.

      Is the 2/1 Oxygen Sensor voltage above 4.8 volts?

      Yes 

      • Go to step  3

      No 

      • Go to step  5
  3. 2/1 OXYGEN SENSOR 
    Fig 1: Measuring Voltage On O2 Sensor Return (Up) Circuit In Oxygen Sensor Harness Connector
    GC0097369Courtesy of CHRYSLER LLC
    1. Measure the voltage on the (K902) O2 Return (Up) circuit in the 2/1 Oxygen Sensor harness connector.

      Is the voltage between 2.40 and 2.60 volts?

      Yes 

      No 

      • Go to step  4
  4. (K902) O2 RETURN (UP) CIRCUIT SHORTED TO GROUND 
    Fig 2: Measuring Resistance Between Ground And O2 Sensor Return (Up) Circuit In Oxygen Sensor Harness Connector
    GC0097370Courtesy 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 (K902) O2 Return (Up) circuit in the 2/1 Oxygen Sensor harness connector.

      Is the resistance below 100 Ohms?

      Yes 

      No 

      • Go to step  5
  5. (K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO GROUND 
    Fig 3: Measuring Resistance Between Ground And O2 Sensor Signal Circuit In Oxygen Sensor Harness Connector
    GC0097371Courtesy of CHRYSLER LLC
    1. Measure the resistance between ground and the (K43) O2 2/1 Signal circuit in the 2/1 Oxygen Sensor harness connector.

      Is the resistance below 100 Ohms?

      Yes 

      No 

      • Go to step  6
  6. (K43) O2 2/1 SIGNAL CIRCUIT SHORTED TO THE (K902) O2 RETURN (UP) CIRCUIT 
    Fig 4: Measuring Resistance Between O2 Sensor Signal Circuit And O2 Sensor Return (Up) Circuit In Oxygen Sensor Harness Connector
    GC0097372Courtesy of CHRYSLER LLC
    1. Measure the resistance between the (K43) O2 2/1 Signal circuit and the (K902) O2 Return (Up) circuit in the 2/1 Oxygen Sensor harness connector.

      Is the resistance below 100 Ohms?

      Yes 

      No 

      • Go to step  7
  7. POWERTRAIN CONTROL MODULE (PCM) 
    1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the 2/1 Oxygen Sensor 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