PR25DD engine
- DTC PRIORITY
If DTC P0139 is detected with DTC P0137 or P0138 perform trouble diagnosis for DTC P0137 or P0138.
Is applicable DTC detected?
YES
Perform diagnosis of applicable. Refer to DTC Index .
NO
GO TO 2.
- 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 P0171 or P0172 detected? Is it difficult to start engine?
YES
Perform trouble diagnosis for DTC P0171 or P0172. DTC Description or DTC Description
NO
GO TO 3.
- CHECK HO2S2 GROUND CIRCUIT
- Turn ignition switch OFF.
- Disconnect heated oxygen sensor 2 harness connector.
- Disconnect ECM harness connector.
- Check the continuity between HO2S2 harness connector and ECM harness connector.
+
-
Continuity
HO2S2
ECM
Connector
Terminal
Connector
Terminal
E78
4
F90
76
Existed
- Also check harness for short to power.
Is the inspection result normal?
YES
GO TO 4.
NO
Repair or replace error-detected parts.
- CHECK HO2S2 INPUT SIGNAL CIRCUIT
- Check the continuity between HO2S2 harness connector and ECM harness connector.
+
-
Continuity
HO2S2
ECM
Connector
Terminal
Connector
Terminal
E78
3
F90
77
Existed
- Check the continuity between HO2S2 harness connector and ground, or ECM harness connector and ground.
+
-
Continuity
HO2S2
Connector
Terminal
E78
3
Ground
Not existed
+
-
Continuity
ECM
Connector
Terminal
F90
77
Ground
Not existed
- Also check harness for short to power.
Is the inspection result normal?
YES
GO TO 5.
NO
Repair or replace error-detected parts.
- Check the continuity between HO2S2 harness connector and ECM harness connector.
- CHECK HEATED OXYGEN SENSOR 2
Check the heated oxygen sensor 2. Refer to Component Inspection .
Is the inspection result normal?
YES
Check intermittent incident. Refer to Inspection .
NO
GO TO 6.
- REPLACE HEATED OXYGEN SENSOR 2
Replace heated oxygen sensor 2. Refer to EXHAUST SYSTEM : Exploded View .
INSPECTION END