Diagnostic Test

OXYGEN SENSOR 1/1 VOLTAGE
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 a scan tool, monitor the 1/1 O2 Sensor volts.
  Is the voltage less than 2.52 volts?
  
  Yes
  - Go To 2
  No
  - Perform the INTERMITTENT CONDITION diagnostic procedure. Refer to INTERMITTENT CONDITION .
CHECK THE (K41) O2 1/1 SIGNAL CIRCUIT VOLTAGE
1. Turn the ignition off.
2. Disconnect the Oxygen Sensor 1/1 harness connector.
3. Turn the ignition on.
4. With a scan tool, monitor the 1/1 O2 Sensor volts.
  Is the voltage above 4.8 volts?
  
  Yes
  - Go To 3
  No
  - Go To 5
OXYGEN SENSOR 1/1
1. Measure the voltage on the (K902) O2 1/1 Return circuit at the Oxygen Sensor 1/1 harness connector.
  Is the voltage between 2.475 and 2.525 volts?
  
  Yes
  - Replace the Oxygen Sensor 1/1 in accordance with the Service Information. Refer to SENSOR, OXYGEN, REMOVAL AND INSTALLATION .
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 4
CHECK THE (K902) O2 1/1 RETURN CIRCUIT FOR A SHORT TO GROUND
1. Turn the ignition off.
2. Disconnect the Powertrain Control Module (PCM) harness connector.
3. Check for continuity between ground and the (K902) O2 1/1 Return circuit at the Oxygen Sensor 1/1 harness connector.
  Is there continuity between ground and the (K902) O2 1/1 Return circuit?
  
  Yes
  - Repair the (K902) O2 1/1 Return circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 8
CHECK THE (K41) O2 1/1 SIGNAL CIRCUIT FOR A SHORT TO GROUND
1. Check for continuity between ground and the (K41) O2 1/1 Signal circuit at the Oxygen Sensor 1/1 harness connector.
  Is there continuity between ground and the (K41) O2 1/1 Signal circuit?
  
  Yes
  - Repair the (K41) O2 1/1 Signal circuit for a short to ground.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 6
CHECK FOR THE (K41) O2 1/1 SIGNAL CIRCUIT SHORTED TO THE (K902) O2 1/1 RETURN CIRCUIT
1. Check for continuity between the (K41) O2 1/1 Signal circuit and the (K902) O2 1/1 Return circuit in the Oxygen Sensor 1/1 harness connector.
  Is there continuity between the (K41) O2 1/1 Signal circuit and the (K902) O2 1/1 Return circuit ?
  
  Yes
  - Repair the short between the (K902) O2 1/1 Return circuit and the (K41) O2 1/1 Signal circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 7
CHECK FOR THE (K41) O2 1/1 SIGNAL CIRCUIT SHORTED TO THE (Z909) GROUND CIRCUIT
1. Check for continuity between the (K41) O2 1/1 Signal circuit and the (Z909) Ground circuit in the Oxygen Sensor 1/1 harness connector.
  Is there continuity between (K41) O2 1/1 Signal circuit and the (Z909) Ground circuit?
  
  Yes
  - Repair the (Z909) Ground circuit for a short to the (K41) O2 1/1 Signal circuit.
  - Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  No
  - Go To 8
POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Oxygen Sensor 1/1 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 .