Diagnostic Test

O2 SENSOR HEATER OPERATION
1. Turn the ignition off.
  NOTE: Wait a minimum of 8 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 a scan tool, actuate the O2 Heater Test.
  NOTE: The DTC needs to be cleared before actuating the Heater Test, if the DTC is not cleared, the Heater Test may not be allowed to actuate.
4. With a scan tool, monitor 2/2 O2 Sensor voltage for at least 2 minutes.
  Does the voltage stay above 4.5 volts?
  
  Yes
  - Go to step 2
  No
  - Refer to the INTERMITTENT CONDITION Diagnostic Procedure. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
O2 SENSOR HEATER ELEMENT
1. Turn the ignition off.
  NOTE: Allow the O2 sensor to cool down to room temperature.
2. Disconnect the O2 Sensor harness connector.
3. Measure the resistance of the 2/2 O2 Heater Element, between the O2 Heater Control terminal and the O2 Heater ground terminal in the O2 Sensor connector.
  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 step 3
  No
  - Verify that there is good pin to terminal contact in the 2/2 O2 Sensor and Powertrain Control Module connectors. Replace the O2 Sensor if no problems were found in the connectors. Refer to Fuel System/Fuel Injection/SENSOR, Oxygen - Removal .
  - Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
(K399) O2 2/2 HEATER CONTROL CIRCUIT OPEN

Fig 1: Measuring Resistance Of O2 Sensor Heater Control Circuit From O2 Sensor Harness Connector To Appropriate Terminal Of Special Tool #8815
Courtesy of CHRYSLER LLC
1. Disconnect the C3 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 PCM Pinout Box 8815 to perform diagnosis.
2. Measure the resistance of the (K399) O2 2/2 Heater Control circuit from the O2 harness connector to the appropriate terminal of special tool #8815.
  Is the resistance below 0.5 of an ohm?
  
  Yes
  - Go to step 4
  No
  - Repair the excessive resistance in the (K399) O2 2/2 Heater Control circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
(Z992) O2 2/2 HEATER GROUND CIRCUIT OPEN

Fig 2: Using 12 Volt Test Light Connected To 12 Volts To Probe O2 Sensor Heater Ground Circuit In O2 Sensor Harness Connector
Courtesy of CHRYSLER LLC
1. Using a 12 volt test light connected to 12 volts, check the (Z992) Ground circuit in the 2/2 Oxygen Sensor 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 5
  No
  - Repair the excessive resistance in the (Z992) O2 2/2 Heater ground circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the 2/2 O2 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. Verify that there is good pin to terminal contact in the 2/2 O2 Sensor and Powertrain Control Module connectors.
4. Refer to any Technical Service Bulletins that may apply.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
  No
  - Replace and program the Powertrain Control Module per Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .