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 the scan tool, monitor 2/2 O2 Sensor voltage for at least 2 minutes.
  Does the voltage stay above 4.5 volts?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to 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 O2 Heater Element across the O2 Sensor 2/2 connector between the O2 Heater Control terminal and the 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 2.88 and 13.0 Ohms?
  
  Yes
  - Go To 3
  No
  - Replace the O2 Sensor.
  - Perform the PCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
CHECK THE (K399) O2 2/2 HEATER CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Disconnect the PCM C1 harness connector.
2. Measure the resistance of the (K399) O2 2/2 Heater Control circuit from the O2 harness connector to the C1 PCM harness connector.
  Is the resistance below 0.5 Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the (K399) O2 2/2 Heater Control circuit for an open or high resistance.
  - Perform the PCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the 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. Verify that there is good pin to terminal contact in the Oxygen Sensor and Powertrain Control Module connectors.
5. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
6. Look for the data to change or for a DTC to set during the wiggle test.
7. Refer to any Technical Service Bulletins that may apply.
  Were there any problems found?
  
  Yes
  - Repair as necessary.
  - Perform the PCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
  No
  - Replace and program the Powertrain Control Module in accordance with the service information.
  - Perform the PCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .