P0138
P0138, P0158 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.
MALFUNCTION A
To judge malfunctions of heated oxygen sensor 2, ECM monitors whether the voltage is unusually high during various driving conditions such as fuel cut.
MALFUNCTION B
To judge malfunctions of heated oxygen sensor 2, ECM monitors whether the minimum voltage of sensor is sufficiently low during various driving conditions such as fuel cut.
DTC CONFIRMATION PROCEDURE
1. 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.
- GO TO 2.
2. PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION A
1.Perform "INSPECTION MODE 5". Description.
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.Drive the vehicle at speed of 100 km/h (62 MPH) for at least 1 minutes.
CAUTION:
Always drive vehicle at a safe speed.
7.Stop the vehicle and set selector lever to P position.
8.Check 1st trip DTC.
Is 1st trip DTC detected?
YES- Go to .
NO-1- With CONSULT: GO TO 3.
NO-2- Without CONSULT: GO TO 5.
3. PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B
NOTE:
For better results, perform "DTC WORK SUPPORT" at a temperature of 0 to 30 �C (32 to 86 �F).
1.Perform "INSPECTION MODE 5". Description.
2.Start engine.
3.Select "DATA MONITOR" mode of "ENGINE" with CONSULT.
4.Warm engine up to the normal operating temperature.
5.Turn ignition switch OFF and wait at least 10 seconds.
6.Turn ignition switch ON.
7.Turn ignition switch OFF and wait at least 10 seconds.
8.Drive the vehicle at speed of 100 km/h (62 MPH) for at least 1 minutes.
CAUTION:
Always drive vehicle at a safe speed.
9.Stop the vehicle and set selector lever to P position.
10.Make sure that "COOLAN TEMP/S" indicates more than 70�C (158�F).
If not, warm up engine and go to next step when "COOLAN TEMP/S" indication reaches 70�C (158�F).
NOTE:
When warm engine up to normal operating temperature, perform "INSPECTION MODE 5". Refer to HBC101, "Description".
11.Open engine hood.
12.Select "HO2S2 (B1) P1146" (for DTC P0138) or "HO2S2 (B2) P1166" (for DTC P0158) of "HO2S2" in
"DTC WORK SUPPORT" mode of "ENGINE with CONSULT.
13.Start engine and follow the instruction of CONSULT display.
NOTE:
It will take at most 10 minutes until "COMPLETED" is displayed.
14.Touch "SELF-DIAG RESULTS".
Which is displayed on CONSULT screen?
OK- INSPECTION END
NG- Go to .
CON NOT BE DIAGNOSED-GO TO 4.
4. PERFORM DTC CONFIRMATION PROCEDURE FOR MALFUNCTION B 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.
5. PERFORM COMPONENT FUNCTION CHECK FOR MALFUNCTION B
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- Go to .
Component Function Check
1. PERFORM COMPONENT FUNCTION CHECK-I
Without CONSULT
1.Perform "INSPECTION MODE 5". Description.
2.Start engine and warm it up to the normal operating temperature.
3.Turn ignition switch OFF and wait at least 10 seconds.
4.Drive the vehicle at speed of 100 km/h (62 MPH) for at least 1 minutes.
CAUTION:
Always drive vehicle at a safe speed.
5.Stop the vehicle and set selector lever to P position.
6.Check the voltage between ECM harness connector terminals under 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 terminals under 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 terminals under the following condition.
Is the inspection result normal?
YES- INSPECTION END
NO- Go to .
Diagnosis Procedure
1. INSPECTION START
Confirm the detected malfunction (A or B). .
Which malfunction is detected?
A- GO TO 2
B- GO TO 9.
2. CHECK GROUND CONNECTION
1.Turn ignition switch OFF.
2.Check ground connection M95. Refer to Ground Inspection in Circuit Inspection.
Is the inspection result normal?
YES- GO TO 3.
NO- Repair or replace ground connection.
3. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1.Disconnect heated oxygen sensor 2 (HO2S2) harness connector.
2.Disconnect ECM harness connector.
3.Check the continuity between HO2S2 harness connector and ECM harness connector.
4.Also check harness for short to ground and short to power.
Is the inspection result normal?
YES- GO TO 4.
NO- Repair open circuit, short to ground or short to power in harness or connectors.
4. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.Check the continuity between HO2S2 harness connector and ECM harness connector.
2.Check the continuity between HO2S2 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 5.
NO- Repair open circuit, short to ground or short to power in harness or connectors.
5. CHECK HO2S2 CONNECTOR FOR WATER
Check connectors for water.
Water should not exist.
Is the inspection result normal?
YES- GO TO 6.
NO- Repair or replace harness or connectors.
6. CHECK HEATED OXYGEN SENSOR 2
.
Is the inspection result normal?
YES- GO TO 8.
NO- GO TO 7.
7. REPLACE HEATED OXYGEN SENSOR 2
Replace malfunctioning heated oxygen sensor 2. Exploded View.
CAUTION:
- Discard any heated oxygen 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 heated oxygen 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
8. CHECK INTERMITTENT INCIDENT
Intermittent Incident.
- INSPECTION END
9. CHECK GROUND CONNECTION
1.Turn ignition switch OFF.
2.Check ground connection M95. Refer to Ground Inspection in Circuit Inspection.
Is the inspection result normal?
YES- GO TO 10.
NO- Repair or replace ground connection.
10. CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE
With CONSULT
1.Clear the mixture ratio self-learning value. Work Procedure.
2.Run engine for at least 10 minutes at idle speed.
Without CONSULT
1.Clear the mixture ratio self-learning value. Work Procedure.
2.Perform "INSPECTION MODE 5". Description.
3.Run engine for at least 10 minutes at idle speed.
Is the 1st trip DTC P0172 or P0175 detected? Is it difficult to start engine?
YES- Perform trouble diagnosis for DTC P0172, P0175. P0172.
NO- GO TO 11.
11. CHECK HO2S2 GROUND CIRCUIT FOR OPEN AND SHORT
1.Turn ignition switch OFF.
2.Disconnect heated oxygen sensor 2 harness connector.
3.Disconnect ECM harness connector.
4.Check the continuity between HO2S2 harness connector and ECM harness connector.
5.Also check harness for short to ground and short to power.
Is the inspection result normal?
YES- GO TO 12.
NO- Repair open circuit, short to ground or short to power in harness or connectors.
12. CHECK HO2S2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
1.Check the continuity between HO2S2 harness connector and ECM harness connector.
2.Check the continuity between HO2S2 harness connector or ECM harness connector and ground.
3.Also check harness for short to power.
Is the inspection result normal?
YES- GO TO 13.
NO- Repair open circuit, short to ground or short to power in harness or connectors.
13. CHECK HEATED OXYGEN SENSOR 2
.
Is the inspection result normal?
YES- GO TO 15.
NO- GO TO 14.
14. REPLACE HEATED OXYGEN SENSOR 2
Replace malfunctioning heated oxygen sensor 2. Exploded View.
CAUTION:
- Discard any heated oxygen 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 heated oxygen 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
15. CHECK INTERMITTENT INCIDENT
Intermittent Incident.
- 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.Perform "INSPECTION MODE 5". Description.
2.Start engine.
3.Select "DATA MONITOR" mode of "ENGINE" with CONSULT.
4.Warm engine up to the normal operating temperature.
5.Turn ignition switch OFF and wait at least 10 seconds.
6.Perform "INSPECTION MODE 5". Description.
7.Start engine and keep the engine speed at 3,000 rpm for at least 1 minute under no load.
8.Let engine idle for 1 minute.
9.Select "FUEL INJECTION" in "ACTIVE TEST" mode of "ENGINE", and select "HO2S2 (B1)/(B2)" as the monitor item with CONSULT.
10.Check "HO2S2 (B1)/(B2)" at idle speed when adjusting "FUEL INJECTION" to �25%.
"HO2S2 (B1)/(B2)" should be above 0.71 V at least once when the "FUEL INJECTION" is +25%.
"HO2S2 (B1)/(B2)" should be below 0.18 V at least once when the "FUEL INJECTION" is 25%.
Is the inspection result normal?
YES- INSPECTION END
NO- GO TO 6.
3. CHECK HEATED OXYGEN SENSOR 2-I
Without CONSULT
1.Perform "INSPECTION MODE 5". Description.
2.Start engine and warm it up to the normal operating temperature.
3.Turn ignition switch OFF and wait at least 10 seconds.
4.Perform "INSPECTION MODE 5". Description.
5.Start engine and keep the engine speed at 3,000 rpm for at least 1 minute under no load.
6.Let engine idle for 1 minute.
7.Check the voltage between ECM harness connector terminals under 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 terminals under 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 terminals under the following condition.
Is the inspection result normal?
YES- INSPECTION END
NO- GO TO 6.
6. REPLACE HEATED OXYGEN SENSOR 2
Replace malfunctioning heated oxygen sensor 2. Exploded View.
CAUTION:
- Discard any heated oxygen 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 heated oxygen 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