PR25DD engine
- INSPECTION START
Confirm the detected malfunction (A or B). DTC Description
Which malfunction is detected?
A
GO TO 2.
B
GO TO 7.
- CHECK HEATED OXYGEN SENSOR 2 CONNECTOR
- Disconnect heated oxygen sensor 2 (HO2S2) harness connector.
- Check that water is not inside connectors.
There is no leakage.
Is the inspection result normal?
YES
GO TO 3.
NO
Repair or replace malfunctioning part.
- CHECK HO2S2 GROUND CIRCUIT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Disconnect heated oxygen sensor 2 (HO2S2) harness connector.
- Check the continuity between HO2S2 harness connector and ECM harness connector.
HO2S2
ECM
Continuity
Connector
Terminal
Connector
Terminal
E78
4
F90
76
Existed
- Also check harness for short to ground and short to power.
Is the inspection result normal?
YES
GO TO 4.
NO
Repair or replace malfunctioning part.
- CHECK HO2S2 INPUT SIGNAL CIRCUIT
- Check the continuity between HO2S2 harness connector and ECM harness connector.
HO2S2
ECM
Continuity
Connector
Terminal
Connector
Terminal
E78
3
F90
77
Existed
- Check the continuity between HO2S2 harness connector and ground, or ECM harness connector and ground.
HO2S2
--
Continuity
Connector
Terminal
E78
3
Ground
Not existed
ECM
--
Continuity
Connector
Terminal
F90
77
Ground
Not existed
- Also check harness for short to ground and short to power.
Is the inspection result normal?
YES
GO TO 5.
NO
Repair or replace malfunctioning part.
- 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
GO TO 6.
- REPLACE HEATED OXYGEN SENSOR 2
Replace heated oxygen sensor 2. Refer to Exploded View (AWD MODELS WITH PR25DD ENGINE) or Exploded View (FWD MODELS WITH PR25DD ENGINE).
INSPECTION END
- PERFORM AIR FUEL RATIO INITIAL LEARNING
- Start engine and warm it up to the normal operating temperature.
- Clear the air fuel ratio initial learning. Refer to Work Procedure .
- Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0172 detected? Is it difficult to start engine?
YES
Perform trouble diagnosis for DTC P0172. DTC Description
NO
GO TO 8.
- CHECK HEATED OXYGEN SENSOR 2 GROUND CIRCUIT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Disconnect heated oxygen sensor 2 (HO2S2) harness connector.
- Check the continuity between HO2S2 harness connector and ECM harness connector.
HO2S2
ECM
Continuity
Connector
Terminal
Connector
Terminal
E78
4
F90
76
Existed
- Also check harness for short to ground and short to power.
Is the inspection result normal?
YES
GO TO 9.
NO
Repair or replace malfunctioning part.
- CHECK HO2S2 INPUT SIGNAL CIRCUIT
- Check the continuity between HO2S2 harness connector and ECM harness connector.
HO2S2
ECM
Continuity
Connector
Terminal
Connector
Terminal
E78
3
F90
77
Existed
- Check the continuity between HO2S2 harness connector and ground, or ECM harness connector and ground.
HO2S2
--
Continuity
Connector
Terminal
E78
3
Ground
Not existed
ECM
--
Continuity
Connector
Terminal
F90
77
Ground
Not existed
- Also check harness for short to ground and short to power.
Is the inspection result normal?
YES
GO TO 10.
NO
Repair or replace malfunctioning part.
- 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
GO TO 11.
- REPLACE HEATED OXYGEN SENSOR 2
Replace heated oxygen sensor 2. Refer to Exploded View (AWD MODELS WITH PR25DD ENGINE) or Exploded View (FWD MODELS WITH PR25DD ENGINE).
INSPECTION END