DTC Diagnosis Procedure
- RETIGHTEN AIR FUEL RATIO SENSOR 1
Loosen and retighten the air fuel ratio (A/F) sensor 1. Refer to EXHAUST MANIFOLD AND THREE WAY CATALYST : Exploded View .
GO TO 2.
- CHECK EXHAUST GAS LEAKAGE
- Start engine and run it at idle.
- Listen for an exhaust gas leakage before three way catalyst (manifold).
Is exhaust gas leakage detected?
YES
Repair or replace malfunctioning part.
NO
GO TO 3.
- CHECK FOR INTAKE AIR LEAKAGE
Listen for an intake air leakage after the mass air flow sensor.
Is intake air leakage detected?
YES
Repair or replace malfunctioning part.
NO
GO TO 4.
- 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, P172, P0174 or P0175 detected? Is it difficult to start engine?
YES
Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to DTC Description .or Refer to DTC Description .
NO
GO TO 5.
- CHECK AIR FUEL RATIO SENSOR 1 POWER SUPPLY
- Turn ignition switch OFF.
- Disconnect air fuel ratio (A/F) sensor 1 harness connector.
- Turn ignition switch ON.
- Check the voltage between A/F sensor 1 harness connector and ground.
DTC
A/F sensor 1
Ground
Voltage
Bank
Connector
Terminal
P014C
P014D
P015A
P015B
1
F133
4
Ground
Battery voltage
P014E
P014F
P015C
P015D
2
F134
4
Is the inspection result normal?
YES
GO TO 7.
NO
GO TO 6.
- CHECK AIR FUEL RATIO SENSOR 1 POWER SUPPLY CIRCUIT
- Turn ignition switch OFF.
- Disconnect IPDM E/R harness connector.
- Check the continuity between A/F sensor 1 harness connector and IPDM E/R harness connector.
DTC
A/F sensor 1
IPDM E/R
Continuity
Bank
Connector
Terminal
Connector
Terminal
P014C
P014D
P015A
P015B
1
F133
4
E14
35
Existed
P014E
P014F
P015C
P015D
2
F134
4
- Also check harness for short to ground and short to power.
Is the inspection result normal?
YES
Perform trouble diagnosis for power supply circuit.
NO
Repair or replace malfunctioning part.
- CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
- Turn ignition switch OFF.
- Disconnect ECM harness connector.
- Check the continuity between A/F sensor 1 harness connector and ECM harness connector.
DTC
A/F sensor 1
ECM
Continuity
Bank
Connector
Terminal
Connector
Terminal
P014C
P014D
P015A
P015B
1
F133
1
F92
79
Existed
2
74
P014E
P014F
P015C
P015D
2
F134
1
F92
69
2
70
- Check the continuity between A/F sensor 1 harness connector and ground, or ECM harness connector and ground.
DTC
A/F sensor 1
Ground
Continuity
Bank
Connector
Terminal
P014C
P014D
P015A
P015B
1
F133
1
Ground
Not Existed
2
P014E
P014F
P015C
P015D
2
F134
1
2
DTC
ECM
Ground
Continuity
Bank
Connector
Terminal
P014C
P014D
P015A
P015B
1
F92
79
Ground
Not Existed
74
P014E
P014F
P015C
P015D
2
F92
69
70
- Also check harness for short to ground and short to power.
Is the inspection result normal?
YES
GO TO 8.
NO
Repair or replace malfunctioning part.
- CHECK A/F SENSOR 1 HEATER
Refer to Component Inspection .
Is the inspection result normal?
YES
GO TO 9.
NO
GO TO 12.
- CHECK MASS AIR FLOW SENSOR
Check mass air flow sensor.
Refer to Component Inspection .
Is the inspection result normal?
YES
GO TO 10.
NO
Replace malfunctioning mass air flow sensor. Refer to AIR CLEANER AND AIR DUCT : Exploded View .
- CHECK PCV VALVE
Refer to POSITIVE CRANKCASE VENTILATION : Periodic Maintenance Operation .
Is the inspection result normal?
YES
GO TO 11.
NO
Repair or replace PCV valve.
- CHECK INTERMITTENT INCIDENT
Refer to Inspection .
Is the inspection result normal?
YES
GO TO 12.
NO
Repair or replace malfunctioning part.
- REPLACE A/F SENSOR 1
Replace malfunctioning A/F sensor 1. Refer to EXHAUST MANIFOLD AND THREE WAY CATALYST : Exploded View .
CAUTION:- Discard any A/F sensor which has been dropped from a height of more than 0.5 m (19.7 in) onto a hard surface such as a concrete floor; use a new one.
- Before installing new A/F sensor, clean exhaust system threads using Oxygen Sensor Thread Cleaner [commercial service tool (J-43897-18 or J-43897-12)] and approved anti-seize lubricant (commercial service tool).
INSPECTION END