Nissan Frontier D22. Manual - part 279

DTC P0139 HO2S2

EC-219

[KA24DE]

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EC

Wiring Diagram

UBS00D4W

BBWA1057E

EC-220

[KA24DE]

DTC P0139 HO2S2

Specification data are reference values and are measured between each terminal and ground.

CAUTION:

Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.

Diagnostic Procedure

UBS00D4X

1. 

RETIGHTEN GROUND SCREWS

1.

Turn ignition switch OFF.

2.

Loosen and retighten engine ground screws.

>> GO TO 2.

TER-

MINAL 

NO.

WIRE 

COLOR

ITEM

CONDITION

DATA (DC Voltage)

56

OR

Heated oxygen sensor 2

[Engine is running]

●

Warm-up condition

●

Revving engine from idle up to 3,000 rpm 
quickly after the following conditions are met.

–

 Keeping the engine speed between 3,500 and 
4,000 rpm for 1 minute and at idle for 1 minute 
under no load

0 - Approximately 1.0V

SEF325V

DTC P0139 HO2S2

EC-221

[KA24DE]

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EC

2. 

CLEAR THE SELF-LEARNING DATA

 With CONSULT-II

1.

Start engine and warm it up to normal operating temperature.

2.

Select “SELF-LEARNING CONT” in “WORK SUPPORT” mode with CONSULT-II.

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 or P0172 detected?
Is it difficult to start engine?

 Without CONSULT-II

1.

Start engine and warm it up to normal operating temperature.

2.

Turn ignition switch “OFF”.

3.

Disconnect mass air flow sensor harness connector, and restart
and run engine for at least 3 seconds at idle speed.

4.

Stop engine and reconnect mass air flow sensor harness con-
nector.

5.

Make sure DTC P0102 is displayed.

6.

Erase the DTC memory. Refer to 

EC-61, "HOW TO ERASE

EMISSION-RELATED DIAGNOSTIC INFORMATION"

 .

7.

Make sure DTC P0000 is displayed.

8.

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 or No

Yes

>> Perform trouble diagnosis for DTC P0171 or P0172. Refer to 

EC-225

  or 

EC-232

 .

No

>> GO TO 3.

3. 

CHECK INPUT SIGNAL CIRCUIT

1.

Disconnect heated oxygen sensor 2 harness connector and ECM harness connector.

2.

Check harness continuity between ECM terminal 56 and HO2S2 terminal 1.
Refer to Wiring Diagram.

3.

Check harness continuity between ECM terminal 56 or HO2S2 terminal 1 and ground.
Refer to Wiring Diagram.

4.

Also check harness for short to ground and short to power.

OK or NG

OK

>> GO TO 5.

NG

>> GO TO 4.

SEF215Z

AEC131A

Continuity should exist.

Continuity should not exist.

EC-222

[KA24DE]

DTC P0139 HO2S2

4. 

DETECT MALFUNCTIONING PART

Check the following.

●

Harness connectors M58, F28

●

Harness for open or short between heated oxygen sensor 2 and ECM

>> Repair open circuit or short to ground or short to power in harness or connectors.

5. 

CHECK GROUND CIRCUIT

1.

Check harness continuity between heated oxygen sensor 2 terminal 4 and engine ground.
Refer to Wiring Diagram.

2.

Also check harness for short to power.

OK or NG

OK

>> GO TO 7.

NG

>> GO TO 6

6. 

DETECT MALFUNCTIONING PART

Check the following.

●

Harness connectors M58, F28

●

Harness for open or short between heated oxygen sensor 2 and engine ground

>> Repair open circuit or short to power in harness or connectors.

7. 

CHECK HEATED OXYGEN SENSOR 2

Refer to 

EC-222, "Component Inspection"

 .

K or NG

OK

>> GO TO 8.

NG

>> Replace heated oxygen sensor 2.

8. 

CHECK INTERMITTENT INCIDENT

Perform 

EC-120, "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT"

 .

>> INSPECTION END.

Component Inspection

UBS00D4Y

HEATED OXYGEN SENSOR 2

 With CONSULT-II

1.

Reconnect all harness connectors disconnected.

2.

Start engine and warm it up to the normal operating temperature.

3.

Turn ignition switch OFF and wait at least 5 seconds.

4.

Start engine and keep engine speed between 3,500 and 4,000 rpm for at least 1 minute under no load.

5.

Let engine idle for 1 minute.

Continuity should exist.