Diagnostic Test

O2 SENSOR HEATER OPERATION
1. Turn the ignition off.
  NOTE:
  Wait a minimum of eight minutes to allow the O2 Sensor to cool down before continuing the test. Allow the O2 Sensor voltage to stabilize between 4.6 and 5.0 Volts.
2. Ignition on, engine not running.
3. With the scan tool, actuate the O2 Heater Test.
4. Using the scan tool, monitor 2/1 O2 Sensor voltage for at least two minutes.
  Does the voltage stay above 4.5 Volts?
  
  Yes
  - Go To 2.
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
O2 SENSOR HEATER ELEMENT
1. Turn the ignition off.
  NOTE:
  Allow the O2 sensor to cool down to room temperature.
2. Disconnect the 2/1 O2 Sensor harness connector.
3. Measure the resistance of the O2 Heater Element across the O2 Sensor connector between the O2 Heater Control terminal and the O2 Heater ground terminal.
  NOTE:
  O2 Heater Element resistance values should be measured at 21.1° C (70° F). The resistance value will vary with different temperature values.
  
  Is the resistance of the O2 Sensor Heater Element between 2.0 and 30.0 Ohms?
  
  Yes
  - Go To 3.
  No
  - Verify that there is good pin to terminal contact in the 2/1 Oxygen Sensor and Powertrain Control Module connectors. If OK, replace the 2/1 O2 Sensor. Refer to SENSOR, OXYGEN, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
(K199) O2 2/1 HEATER CONTROL CIRCUIT OPEN

Fig 1: Checking O2 Sensor 2/1 Heater Control Circuit For An Open
Courtesy of CHRYSLER LLC
1. Disconnect the C2 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 the PCM Pinout Box (special tool #8815A, Kit, NGC, 38 Position) to perform diagnosis.
2. Measure the resistance of the (K199) O2 2/1 Heater Control circuit from the O2 harness connector to the appropriate terminal of PCM Pinout Box (special tool #8815A, Kit, NGC, 38 Position).
  Is the resistance below 0.5 of an Ohm?
  
  Yes
  - Go To 4.
  No
  - Repair the excessive resistance in the (K199) O2 2/1 Heater Control circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
(Z903) O2 SENSOR HEATER GROUND CIRCUIT OPEN

Fig 2: Measuring Resistance Between Ground And O2 Sensor Heater Ground Circuit In O2 Sensor Harness Connector
Courtesy of CHRYSLER LLC
1. Measure the resistance between ground and the (Z903) O2 Heater ground circuit in the O2 Sensor harness connector.
  Is the resistance below 0.5 of an Ohm?
  
  Yes
  - Go To 5.
  No
  - Repair the excessive resistance in the (Z903) O2 Heater ground circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Oxygen Sensor 2/1 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. Verify that there is good pin to terminal contact in the Oxygen Sensor and Powertrain Control Module connectors.
4. Perform any Technical Service Bulletins that may apply.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Replace and program the Powertrain Control Module in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .