P2A03

P2A00, P2A03 A/F SENSOR 1





Component Description






The air fuel ratio (A/F) sensor 1 is a planar one-cell limit current sensor. The sensor element of the A/F sensor 1 is composed an electrode layer, which transports ions. It has a heater in the element.
The sensor is capable of precise measurement lambda = 1, but also in the lean and rich range. Together with its control electronics, the sensor outputs a clear, continuous signal throughout a wide lambda range.
The exhaust gas components diffuse through the diffusion layer at the sensor cell. An electrode layer is applied voltage, and this current relative oxygen density in lean. Also this current relative hydrocarbon density in rich.
Therefore, the A/F sensor 1 is able to indicate air fuel ratio by this electrode layer of current. In addition, a heater is integrated in the sensor to ensure the required operating temperature of about 800�C(1,472�F).









On Board Diagnosis Logic
To judge the malfunction, the A/F signal computed by ECM from the A/F sensor 1 signal is monitored so it will not shift to LEAN side or RICH side.









DTC Confirmation Procedure

NOTE:
If DTC Confirmation Procedure has been previously conducted, always perform the following before conducting the next step.
1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V at idle.

WITH CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.
5. Turn ignition switch ON and select "SELF-LEARNING CONT" in "WORK SUPPORT" mode with CONSULT-III.
6. Clear the self-learning coefficient by touching "CLEAR".
7. Turn ignition switch OFF and wait at least 10 seconds.
8. Turn ignition switch ON.
9. Turn ignition switch OFF and wait at least 10 seconds.
10. Start engine and keep the engine speed between 3,500 and 4,000 rpm for 1 minute under no load.
11. Let engine idle for 1 minute.
12. Keep engine speed between 2,500 and 3,000 rpm for 20 minutes.
13. Check 1st trip DTC.
14. If 1st trip DTC is detected, go to SEE Diagnosis Procedure.

WITH GST
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF and wait at least 10 seconds.
3. Turn ignition switch ON.
4. Turn ignition switch OFF and wait at least 10 seconds.





5. Disconnect mass air flow sensor harness connector.
6. Start engine and let it idle for at least 5 seconds.
7. Stop engine and reconnect mass air flow sensor harness connector.
8. Select Service $03 with GST and make sure that DTC P0102 is detected.
9. Select Service $04 with GST and erase the DTC P0102.
10. Start engine and keep the engine speed between 3,500 and
4,000 rpm for 1 minute under no load.
11. Let engine idle for 1 minute.
12. Keep engine speed between 2,500 and 3,000 rpm for 20 minutes.
13. Select Service $07 with GST.
If 1st trip DTC is detected, go to SEE Diagnosis Procedure.




Diagnosis Procedure
1.CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Power Supply And Ground Circuit.





OK or NG
OK - GO TO 2.
NG - Repair or replace ground connections.
2.RETIGHTEN AIR FUEL RATIO (A/F) SENSOR 1
Loosen and retighten the air fuel ratio (A/F) sensor 1. Removal And Installation (Exhaust Manifold).
- GO TO 3.
3.CHECK FOR INTAKE AIR LEAK
1. Start engine and run it at idle.
2. Listen for an intake air leak after the mass air flow sensor.
OK or NG
OK - GO TO 4.
NG - Repair or replace.
4.CLEAR THE SELF-LEARNING DATA.
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select "SELF-LEARNING CONT" in "WORK SUPPORT" mode with CONSULT-III.
3. Clear the self-learning control coefficient by touching "CLEAR".
4. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172, P0174 or P0175 detected?
Is it difficult to start engine?
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.





3. Disconnect mass air flow sensor harness connector.
4. Restart engine and let it idle for at least 3 seconds.
5. Stop engine and reconnect mass air flow sensor harness connector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. On Board Diagnosis Function (Without CONSULT-III) or CONSULT-III Function (ECM) (With CONSULT-III).
8. Make sure DTC P0000 is displayed.
9. Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0171, P0172 or P0174, P0175 detected?
Is it difficult to start engine?
Yes or No
Yes - Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. P0171 P0171 or P0172 P0172.
No - GO TO 5.
5.CHECK HARNESS CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect A/F sensor 1 harness connector.





3. Check harness connector for water.






OK or NG
OK - GO TO 6.
NG - Repair or replace harness connector.
6.CHECK A/F SENSOR 1 POWER SUPPLY CIRCUIT
1. Turn ignition switch ON.





2. Check voltage between A/F sensor 1 terminal 4 and ground with
CONSULT-III or tester.






OK or NG
OK - GO TO 8.
NG - GO TO 7.
7.DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E2, F32
- IPDM E/R connector E119
- 15 A fuse (No.54)
- Harness for open or short between A/F sensor 1 and fuse
- Repair or replace harness or connectors.
8.CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect ECM harness connector.
3. Check harness continuity between A/F sensor 1 terminal and ECM terminal as follows. Refer to Wiring Diagram.






4. Check harness continuity between the following terminals and ground. Refer to Wiring Diagram.






5. Also check harness for short to ground and short to power.
OK or NG
OK - GO TO 9.
NG - Repair open circuit or short to ground or short to power in harness or connectors.
9.CHECK A/F SENSOR 1 HEATER
P0031.
OK or NG
OK - GO TO 10.
NG - GO TO 11.
10.CHECK INTERMITTENT INCIDENT
Perform Intermittent Incident.
OK or NG
OK - GO TO 11.
NG - Repair or replace.
11.REPLACE A/F SENSOR 1
Replace malfunctioning A/F sensor 1. 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 Heated Oxygen Sensor
Thread Cleaner tool J-43897-18 or J-43897-12 and approved anti-seize lubricant.
- GO TO 12.
12.CONFIRM A/F ADJUSTMENT DATA
1. Turn ignition switch ON.
2. Select "A/F ADJ-B1" and "A/F ADJ-B2" in "DATA MONITOR" mode with CONSULT-III.
3. Make sure that "0" is displayed on CONSULT-III screen.
OK or NG
OK - INSPECTION END
NG - GO TO 13.
13.CLEAR A/F ADJUSTMENT DATA
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select "SELF-LEARNING CONT" in "WORK SUPPORT" mode with CONSULT-III.
3. Clear the self-learning control coefficient by touching "CLEAR".
Without CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.





3. Disconnect mass air flow sensor harness connector.
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness connector.
6. Make sure DTC P0102 is displayed.
7. Erase the DTC memory. On Board Diagnosis Function (Without CONSULT-III) or CONSULT-III Function (ECM) (With CONSULT-III)..
8. Make sure DTC P0000 is displayed.
- GO TO 14.
14.CONFIRM A/F ADJUSTMENT DATA
1. Turn ignition switch OFF and then ON.
2. Select "A/F ADJ-B1" and "A/F ADJ-B2" in "DATA MONITOR" mode with CONSULT-III.
3. Make sure that "0" is displayed on CONSULT-III screen.
OK or NG
OK - INSPECTION END