Diagnostic Test

CHECK FOR AN ACTIVE DTC
NOTE:
After the repairs have been made, verify proper O2 Sensor operation. If all the O2 Sensor voltage readings have not returned to normal, follow the diagnostic procedure for the remaining O2 Sensors.

NOTE:
Check for contaminants that may have damaged the O2 Sensor: contaminated fuel, unapproved silicone, oil and coolant.
1. Start the engine and allow the engine to reach normal operating temperature.
2. Test drive the vehicle according to the set conditions.
3. With the scan tool, read DTCs.
  Is the DTC active or pending?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK THE EXHAUST SYSTEM FOR LEAKS
1. Perform the CHECKING THE EXHAUST SYSTEM FOR LEAKS test procedure. Refer to CHECKING THE EXHAUST SYSTEM FOR LEAKS .
  Were any exhaust leaks found?
  
  Yes
  - Repair or replace the leaking exhaust parts as necessary.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 3
CHECK THE (K141) O2 SENSOR 1/2 SIGNAL CIRCUIT
1. Turn the ignition off.
2. Disconnect the O2 Sensor 1/2 harness connector.
3. Turn the ignition ON.
4. Measure the voltage between ground and the (K141) O2 Sensor 1/2 Signal circuit in the O2 Sensor 1/2 harness connector.
  Is the voltage between 0.09 and 0.12 volts?
  
  Yes
  - Go To 4
  No
  - Check the O2 Sensor 1/2 Signal circuit for a short to ground, open or short to voltage. If OK, replace and program the PCM in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE (K904) O2 SENSOR RETURN CIRCUIT
1. Measure the voltage between ground and the (K904) O2 Sensor Return circuit at the O2 Sensor 1/2 harness connector.
  Is the voltage at 0.11 volts?
  
  Yes
  - Go To 5
  No
  - Check the (K904) O2 Sensor Return circuit for a short to ground, open or short to voltage. If OK, replace and program the PCM in accordance with the Service Information. Refer to MODULE, POWERTRAIN CONTROL (PCM), REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
CHECK THE OXYGEN SENSOR 1/2 CIRCUITS AND CONNECTIONS
1. Using the appropriate SYSTEM 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 the Oxygen Sensor 1/2 circuits or connections.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Replace the Oxygen Sensor 1/2 in accordance with the Service Information. Refer to SENSOR, OXYGEN, REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .