Diagnostic Test
- OXYGEN SENSOR 1/1 VOLTAGE
- 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.
- With a scan tool, monitor the 1/1 O2 Sensor Volts.
Is the voltage less than 2.52 volts?
Yes
- Go to step 2
No
- Perform the CHECKING FOR AN INTERMITTENT DTC diagnostic procedure. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
- Start the engine and allow it to reach normal operating temperature.
- (K41) O2 1/1 SIGNAL CIRCUIT VOLTAGE
- OXYGEN SENSOR 1/1 RETURN CIRCUIT VOLTAGE
- (K902) O2 1/1 RETURN CIRCUIT SHORTED TO GROUND
- Turn the ignition off.
- Disconnect the Powertrain Control Module (PCM) harness connector.
- Measure the resistance between ground and the (K902) O2 1/1 Return circuit in the Oxygen Sensor 1/1 harness connector.
Is the resistance below 100 Ohms?
Yes
- Repair the (K902) O2 1/1 Return circuit for a short to ground.
- Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
No
- Go to step 8
- (K41) O2 1/1 SIGNAL CIRCUIT SHORTED TO GROUND
- Measure the resistance between ground and the (K41) O2 1/1 Signal circuit in the Oxygen Sensor 1/1 harness connector.
Is the resistance below 100 Ohms?
Yes
- Repair the (K41) O2 1/1 Signal circuit for a short to ground.
- Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
No
- Go to step 6
- Measure the resistance between ground and the (K41) O2 1/1 Signal circuit in the Oxygen Sensor 1/1 harness connector.
- (K41) O2 1/1 SIGNAL CIRCUIT SHORTED TO THE (K902) O2 1/1 RETURN CIRCUIT
- Measure the resistance 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 the resistance below 100 Ohms?
Yes
- Repair the short between the (K902) O2 1/1 Return circuit and the (K41) O2 1/1 Signal circuit.
- Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
No
- Go to step 8
- Measure the resistance between the (K41) O2 1/1 Signal circuit and the (K902) O2 1/1 Return circuit in the Oxygen Sensor 1/1 harness connector.
- OXYGEN SENSOR 1/1
- Turn the ignition off.
- Inspect the wiring and connectors between the Oxygen Sensor 1/1 and the Powertrain Control Module (PCM).
- Look for any chafed, pierced, pinched, or partially broken wires.
- Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the related connectors.
Were any problems found?
Yes
- Repair as necessary.
- Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
No
- Replace the Oxygen Sensor 1/1 in accordance with the Service Information.
- Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
- POWERTRAIN CONTROL MODULE (PCM)
- 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).
- Look for any chafed, pierced, pinched, or partially broken wires.
- Look for broken, bent, pushed out or corroded terminals.
- Perform any Technical Service Bulletins that may apply.
Were any problems found?
Yes
- Repair as necessary.
- Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .
No
- Replace and program the Powertrain Control Module (PCM) in accordance with the Service Information.
- Perform the PCM VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure .