FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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P0139




P0139 HO2S2

DTC Logic


DTC DETECTION LOGIC






The heated oxygen sensor 2 has a much longer switching time between rich and lean than the air fuel ratio (A/F) sensor 1. The oxygen storage capacity of the three way catalyst 1 causes the longer switching time. To judge the malfunctions of heated oxygen sensor
2, ECM monitors whether the switching response of the sensor's voltage is faster than specified during various driving conditions such as fuel cut.






DTC CONFIRMATION PROCEDURE


1. INSPECTION START

Do you have CONSULT?
Do you have CONSULT?
YES- GO TO 2.
NO- GO TO 7.

2. PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.
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:
For better results, perform "DTC WORK SUPPORT" at a temperature of 0 to 30�C (32 to 86�F).

- GO TO 3.

3. PERFORM DTC CONFIRMATION PROCEDURE

With CONSULT
1.Turn ignition switch ON and select "DATA MONITOR" mode of "ENGINE" using CONSULT.
2.Start engine and warm it up to the normal operating temperature.
3.Turn ignition switch OFF and wait at least 10 seconds.
4.Turn ignition switch ON.
5.Turn ignition switch OFF and wait at least 10 seconds.
6.Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
7.Let engine idle for 1 minute.
8.Make sure that "COOLAN TEMP/S" indicates more than 70�C (158�F).
9.Drive the vehicle in a proper at 60 km/h (38MPH) and maintain the speed.

CAUTION:
Always drive vehicle at a safe speed.
10.Release the accelerator pedal fully at least 5 seconds.

CAUTION:
- Enable engine brake.
- Always drive carefully.
- Never apply brake when releasing the accelerator pedal.
11.Repeat step 9 and 10 at least 8 times.
12.Check the following item of "DATA MONITOR".





Is "CMPLT" displayed on CONSULT screen?
YES- GO TO 6.
NO-1: "CMPLT" is not displayed on DIAG 1-Perform DTC confirmation procedure again.
NO-2: "CMPLT" is not displayed on DIAG 2-GO TO 4.

4. PERFORM DTC WORK SUPPORT

1.Open engine hood.
2.Select "HO-2S2 (B1) P0139" in "DTC WORK SUPPORT" mode of "ENGINE" using CONSULT.
3.Start engine and follow the instruction of CONSULT display.
NOTE:
It will take at most 10 minutes until "COMPLETED" is displayed.
Is "COMPLETED" displayed on CONSULT screen?
YES- GO TO 6.
NO- GO TO 5.

5. PERFORM DTC CONFIRMATION PROCEDURE AGAIN

1.Turn ignition switch OFF and leave the vehicle in a cool place (soak the vehicle).
2.Perform DTC confirmation procedure again.
- GO TO 3.

6. PERFORM SELF-DIAGNOSIS

With CONSULT
Perform ECM self-diagnosis.
Is DTC "P0139" detected?
YES- Proceed to .
NO- INSPECTION END

7. PERFORM COMPONENT FUNCTION CHECK

Perform component function check. .
NOTE:
Use component function check to check the overall function of the heated oxygen sensor 2 circuit. During this check, a 1st trip DTC might not be confirmed.
Is the inspection result normal?
YES- INSPECTION END
NO- Proceed to .


Component Function Check


1. PERFORM COMPONENT FUNCTION CHECK-I

Without CONSULT
1.Start engine and warm it up to normal operating temperature.
2.Turn ignition switch OFF and wait at least 10 seconds.
3.Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4.Let engine idle for 1 minute.
5.Check the voltage between ECM harness connector and ground as per the following condition.





Is the inspection result normal?
YES- INSPECTION END
NO- GO TO 2.

2. PERFORM COMPONENT FUNCTION CHECK-II

Check the voltage between ECM harness connector and ground as per the following condition.





Is the inspection result normal?
YES- INSPECTION END
NO- GO TO 3.

3. PERFORM COMPONENT FUNCTION CHECK-III

Check the voltage between ECM harness connector and ground as per the following condition.





Is the inspection result normal?
YES- INSPECTION END
NO- Proceed to P0137.


Diagnosis Procedure


1. CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE

1.Clear the mixture ratio self-learning value. Work Procedure.
2.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. P0171 or P0172.
NO- GO TO 2.

2. CHECK HO2S2 GROUND CIRCUIT

1.Turn ignition switch OFF.
2.Disconnect heated oxygen sensor 2 harness connector.
3.Disconnect ECM harness connector.
4.Check the continuity between HO-2S2 harness connector and ECM harness connector.





5.Also check harness for short to power.
Is the inspection result normal?
YES- GO TO 3.
NO- Repair or replace error-detected parts.

3. CHECK HO2S2 INPUT SIGNAL CIRCUIT

1.Check the continuity between HO-2S2 harness connector and ECM harness connector.





2.Check the continuity between HO-2S2 harness connector and ground, or ECM harness connector and ground.










3.Also check harness for short to power.
Is the inspection result normal?
YES- GO TO 4.
NO- Repair or replace error-detected parts.

4. CHECK HEATED OXYGEN SENSOR 2

Check the heated oxygen sensor 2. .
Is the inspection result normal?
YES- Check intermittent incident. Intermittent Incident.
NO- GO TO 5.

5. REPLACE HEATED OXYGEN SENSOR 2

Replace heated oxygen sensor 2. Exploded View.

CAUTION:
- Discard any 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 sensor, clean exhaust system threads using Oxygen Sensor Thread Cleaner
[commercial service tool (J-43897-18 or J43897-12)] and approved Anti-seize Lubricant (commercial service tool).
- INSPECTION END


Component Inspection


1. INSPECTION START

Do you have CONSULT?
Do you have CONSULT?
YES- GO TO 2.
NO- GO TO 3.

2. CHECK HEATED OXYGEN SENSOR 2

With CONSULT
1.Turn ignition switch ON and select "DATA MONITOR" mode of "ENGINE" using CONSULT.
2.Start engine and warm it up to normal operating temperature.
3.Turn ignition switch OFF and wait at least 10 seconds.
4.Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
5.Let engine idle for 1 minute.
6.Select "FUEL INJECTION" in "ACTIVE TEST" mode of "ENGINE" using CONSULT, and select "HO-2S2
(B1)" as the monitor item with CONSULT.
7.Check "HO-2S2 (B1)" at idle speed when adjusting "FUEL INJECTION" to ± 25%.










Is the inspection result normal?
YES- INSPECTION END
NO- GO TO 6.

3. CHECK HEATED OXYGEN SENSOR 2-I

Without CONSULT
1.Start engine and warm it up to normal operating temperature.
2.Turn ignition switch OFF and wait at least 10 seconds.
3.Start engine and keep the engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.
4.Let engine idle for 1 minute.
5.Check the voltage between ECM harness connector and ground as per the following condition.





Is the inspection result normal?
YES- INSPECTION END
NO- GO TO 4.

4. CHECK HEATED OXYGEN SENSOR 2-II

Check the voltage between ECM harness connector and ground as per the following condition.





Is the inspection result normal?
YES- INSPECTION END
NO- GO TO 5.

5. CHECK HEATED OXYGEN SENSOR 2-III

Check the voltage between ECM harness connector and ground as per the following condition.





Is the inspection result normal?
YES- INSPECTION END
NO- GO TO 6.

6. REPLACE HEATED OXYGEN SENSOR 2

Replace heated oxygen sensor 2. Exploded View.

CAUTION:
- Discard any 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 sensor, clean exhaust system threads using Oxygen Sensor Thread Cleaner
[commercial service tool (J-43897-18 or J43897-12)] and approved Anti-seize Lubricant (commercial service tool).
- INSPECTION END