DTC Diagnosis Procedure
- CHECK DTC PRIORITY
If DTC P0103 is displayed with DTC P0643, first perform the confirmation procedure (trouble diagnosis) for DTC P0643.
Is DTC P0643 detected?
YES
Perform diagnosis of applicable. Refer to DTC Description .
NO
GO TO 2.
- CHECK HARNESS CONNECTOR
- Disconnect mass air flow sensor harness connector and ECM harness connector.
- Connect mass air flow sensor harness connector and ECM harness connector.
- Perform DTC confirmation procedure. Refer to Confirmation Procedure .
Is DTC detected?
YES
GO TO 3.
NO
INSPECTION END
- CHECK MASS AIR FLOW SENSOR POWER SUPPLY
- Disconnect mass air flow sensor harness connector.
- Turn ignition switch ON.
- Check the voltage between mass air flow sensor harness connector and ground.
+
-
Voltage
(Approx.)
Mass air flow sensor
Bank
Connector
Terminal
1
F99
1
Ground
5 V
Is the inspection result normal?
YES
GO TO 5.
NO
GO TO 4.
- CHECK MASS AIR FLOW SENSOR POWER SUPPLY CIRCUIT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Check the continuity between mass air flow sensor harness connector and ECM harness connector.
Mass air flow sensor
ECM
Continuity
Bank
Connector
Terminal
Connector
Terminal
1
F99
1
F143
33
Existed
- Also check harness for short to power and short to ground.
Is the inspection result normal?
YES
Perform the trouble diagnosis for ECM power supply circuit. Refer to Diagnosis Procedure .
NO
Repair or replace error-detected parts.
- CHECK MASS AIR FLOW SENSOR GROUND CIRCUIT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Check the continuity between mass air flow sensor harness connector and ECM harness connector.
Mass air flow sensor
ECM
Continuity
Bank
Connector
Terminal
Connector
Terminal
1
F99
3
F143
30
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 ECM GROUND CIRCUIT
- Check the continuity between ECM harness connector and ground.
ECM
--
Continuity
Connector
Terminal
F143
3
Ground
Existed
F142
87
88
E152
199
201
204
- Also check harness for short to power.
Is the inspection result normal?
YES
GO TO 7.
NO
Repair or replace error-detected parts.
- Check the continuity between ECM harness connector and ground.
- CHECK MASS AIR FLOW SENSOR INPUT SIGNAL CIRCUIT
- Check the continuity between mass air flow sensor harness connector and ECM harness connector.
Mass air flow sensor
ECM
Continuity
Bank
Connector
Terminal
Connector
Terminal
1
F99
2
F143
41
Existed
- Also check harness for short to power and short to ground.
Is the inspection result normal?
YES
GO TO 8.
NO
Repair open circuit, short to ground or short to power in harness or connectors.
- Check the continuity between mass air flow sensor harness connector and ECM harness connector.
- CHECK MASS AIR FLOW SENSOR
Refer to Component Inspection .
Is the inspection result normal?
YES
INSPECTION END
NO
Replace malfunctioning mass air flow sensor. Refer to AIR CLEANER AND AIR DUCT : Exploded View .