DTC Diagnosis Procedure
- DTC PRIORITY
If DTC P0159 is detected with DTC P0157 or P0158, first perform the confirmation procedure (trouble diagnosis) for DTC P0157 or P0158.
Is DTC P0157 or P0158 detected?
YES
Perform diagnosis of applicable.
- P0157: Refer to DTC Description .
- P0158: Refer to DTC Description .
NO
GO TO 2.
- CHECK GROUND CONNECTION
- Turn ignition switch OFF.
- Check ground connection E191. Refer to Ground Inspection Inspection .
Is the inspection result normal?
YES
GO TO 3.
NO
Repair or replace ground connection.
- CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE
- Clear the mixture ratio self-learning value. Refer to Work Procedure .
- Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0174 or P0175 detected? Is it difficult to start engine?
YES
Perform trouble diagnosis for DTC P0174 or P0175. Refer to DTC Description . or Refer to DTC Description .
NO
GO TO 4.
- CHECK HO2S2 GROUND CIRCUIT
- Turn ignition switch OFF.
- Disconnect heated oxygen sensor 2 (HO2S2) harness connector.
- Disconnect ECM harness connector.
- Check the continuity between HO2S2 harness connector and ECM harness connector.
HO2S2
ECM
Continuity
Bank
Connector
Terminal
Connector
Terminal
2
F126
4
F143
81
Existed
- Also check harness for short to power.
Is the inspection result normal?
YES
GO TO 5.
NO
Repair open circuit, short to ground or short to power in harness or connectors.
- CHECK HO2S2 INPUT SIGNAL CIRCUIT
- Check the continuity between HO2S2 harness connector and ECM harness connector.
HO2S2
ECM
Continuity
Bank
Connector
Terminal
Connector
Terminal
2
F126
3
F143
51
Existed
- Check the continuity between HO2S2 harness connector and ground, or ECM harness connector and ground.
HO2S2
--
Continuity
Bank
Connector
Terminal
2
F126
3
Ground
Not existed
ECM
--
Continuity
Bank
Connector
Terminal
2
F143
51
Ground
Not existed
- Also check harness for short to power.
Is the inspection result normal?
YES
GO TO 6.
NO
Repair open circuit, short to ground or short to power in harness or connectors.
- Check the continuity between HO2S2 harness connector and ECM harness connector.
- CHECK HEATED OXYGEN SENSOR 2
Refer to Component Inspection .
Is the inspection result normal?
YES
INSPECTION END
NO
Replace malfunctioning heated oxygen sensor 2. Refer to CATALYST : Exploded View .