Diagnostic Test

CHECK FOR AN ACTIVE DTC
1. Start the engine and allow it to reach normal operating temperature.
  WARNING:
  When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.
2. With the scan tool, read DTCs.
  Is the DTC active?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK THE (K299) O2 SENSOR 1/2 HEATER CONTROL CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the Oxygen Sensor 1/2 harness connector.
3. Disconnect the PCM C2 harness connector.
4. Check for continuity between ground and the (K299) O2 Sensor 1/2 Heater Control circuit in the Oxygen Sensor 1/2 harness connector.
  Is there continuity between ground and the (K299) O2 Sensor 1/2 Heater Control circuit?
  
  Yes
  - Repair the (K299) O2 Sensor 1/2 Heater Control circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (K299) O2 SENSOR 1/2 HEATER CONTROL CIRCUIT FOR A SHORT TO THE (Z909) GROUND CIRCUIT
1. Check for continuity between the (K299) O2 Sensor 1/2 Heater Control circuit and the (Z909) Ground circuit in the Oxygen Sensor 1/1 harness connector.
  Is there continuity between the (K299) O2 Sensor 1/2 Heater Control circuit and the (Z909) Ground circuit?
  
  Yes
  - Repair the short between the (K299) O2 Sensor 1/2 Heater Control circuit and the (Z909) Ground circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 4
OXYGEN SENSOR 1/2
1. Reconnect the PCM C2 harness connector.
2. Turn the ignition on.
3. With the scan tool, actuate the Oxygen Sensor 1/2 control to the maximum allowable percentage.
4. Using a 12-volt test light connected to ground, check the (K299) O2 1/2 Heater Control circuit in the Oxygen Sensor 1/2 harness connector.
  NOTE:
  The test light should flash dimly.
5. With the scan tool, actuate the Oxygen Sensor 1/2 control to the OFF (0%) position.
6. Using a 12-volt test light connected to ground, check the (K299) O2 1/2 Heater Control circuit in the Oxygen Sensor 1/2 harness connector.
  NOTE:
  The test light should not be illuminated.
  
  Does the test light flash dimly with the actuator ON (25%) and not illuminated with the actuator OFF (0%)?
  
  Yes
  - Replace the Oxygen Sensor 1/2 in accordance with the Service Information.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 5
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Oxygen Sensor 1/2 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 Service Bulletins that may apply.
  Were 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 (PCM) in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL, REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .