Diagnostic Test

CHECK THE ABILITY OF THE PCM TO READ THE OXYGEN SENSOR 1/2 HEATER CONTROL VOLTAGE VALUE
1. Turn the ignition off.
  NOTE:
  Wait a minimum of 8 minutes to allow the sensor to cool down before continuing. The sensor voltage should stabilize between 2.47 and 2.52 volts.
2. Turn the ignition on.
3. With a scan tool, actuate the Oxygen Sensor 1/2 heater control.
4. With the scan tool, monitor O2 Sensor 1/2 volts for at least two minutes.
  Does the voltage stay between 2.47 and 2.52 volts?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK THE OXYGEN SENSOR 1/2 HEATER ELEMENT FOR RESISTANCE VALUE TO GROUND
1. Turn the ignition off.
  NOTE:
  Wait a minimum of 8 minutes to allow the sensor to cool down before continuing.
2. Disconnect the Oxygen Sensor 1/2 harness connector.
3. Check for continuity of the O2 Sensor 1/2 heater element across the Oxygen Sensor 1/2 connector between the (K299) heater control terminal and the (Z909) ground terminal.
  NOTE:
  The O2 heater element resistance should be measured at 70°F (21.1°C). The resistance value will vary at different temperatures.
  
  Is the resistance between 2.0 and 30.0 Ohms?
  
  Yes
  - Go To 3
  No
  - Replace the Oxygen Sensor 1/2 in accordance with the Service Information. Refer to SENSOR, OXYGEN, REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE (K299) O2 SENSOR 1/2 HEATER CONTROL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Turn the ignition off.
2. Disconnect the Oxygen Sensor 1/2 harness connector.
3. Disconnect the PCM C2 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 GPEC Diagnostic Adaptor to perform the diagnosis.
4. Connect the (special tool #10436, Adapter, GPEC Diagnostic).
5. Check for continuity of the (K299) O2 Sensor 1/2 Heater Control circuit between the Oxygen Sensor 1/2 harness connector and the GPEC Adaptor.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 4
  No
  - Repair the (K299) O2 Sensor 1/2 Heater Control circuit for an open or high resistance.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE (Z909) GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE
1. Check for continuity between a good chassis ground and the (Z909) Ground circuit in the O2 Sensor harness connector.
  Is the resistance below 3.0 Ohms?
  
  Yes
  - Go To 5
  No
  - Repair the excessive resistance in the (Z909) Ground circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK RELATED HARNESS CONNECTIONS
1. Disconnect all PCM harness connectors.
2. Disconnect all related in-line harness connections (if equipped).
3. Disconnect the related component harness connectors.
4. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
  - Proper connector installation.
  - Damaged connector locks.
  - Corrosion.
  - Other signs of water intrusion.
  - Weather seal damage (if equipped).
  - Bent terminals.
  - Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
  - Terminals that have been pushed back into the connector cavity.
  - Check for spread terminals and verify proper terminal tension.
  Repair any conditions that are found.
5. Connect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
8. With the scan tool, erase DTCs.
9. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
10. With the scan tool, read DTCs.
  Did the DTC return?
  
  Yes
  - Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - The wiring or poor connection problem has been repaired.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .