Nissan Pathfinder. Instruction - part 484

EC-242

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P0139, P0159 HO2S2

2. Disconnect heated oxygen sensor 2 harness connector.

3. Disconnect ECM harness connector.

4. Check the continuity between heated oxygen sensor 2 (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 3.

NO

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

3.

CHECK HO2S2 INPUT SIGNAL CIRCUIT

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 4.

NO

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

4.

CHECK HEATED OXYGEN SENSOR 2

Check heated oxygen sensor 2. Refer to 

EC-243, "Component Inspection"

.

Is the inspection result normal?

YES

>> Check intermittent incident. Refer to 

GI-49, "Intermittent Incident"

.

NO

>> Replace malfunctioning heated oxygen sensor 2. Refer to 

EM-31, "Removal and Installation

(bank 2)"

, 

EM-33, "Removal and Installation (bank 1)"

.

Component Inspection

INFOID:0000000009178165

1.

INSPECTION START

Will CONSULT be used?
Will CONSULT be used?

YES

>> GO TO 2.

DTC

HO2S2

ECM

Continuity

Bank

Connector

Terminal

Connector

Terminal

P0139

1

F13

1

F52

59

Existed

P0159

2

F12

1

DTC

HO2S2

ECM

Continuity

Bank

Connector

Terminal

Connector

Terminal

P0139

1

F13

4

F52

57

Existed

P0159

2

F12

4

58

DTC

HO2S2

Ground

Continuity

Bank

Connector

Terminal

P0139

1

F13

4

Ground

Not existed

P0159

2

F12

4

DTC

ECM

Ground

Continuity

Connector

Terminal

P0139

F52

57

Ground

Not existed

P0159

58

P0139, P0159 HO2S2

EC-243

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

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EC

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NO

>> GO TO 3.

2.

CHECK HEATED OXYGEN SENSOR 2

With CONSULT

1. Turn ignition switch ON and select “DATA MONITOR” mode with 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. 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, and select “HO2S2 (B1)/(B2)” as the monitor item

with CONSULT.

7. Check “HO2S2 (B1)/(B2)” at idle speed when adjusting “FUEL INJECTION” to 

± 25%.

“HO2S2 (B1)/(B2)” should be above 0.68 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

>> Replace malfunctioning heated oxygen sensor 2. Refer to 

EM-31, "Removal and Installation

(bank 2)"

, 

EM-33, "Removal and Installation (bank 1)"

.

3.

CHECK HEATED OXYGEN SENSOR 2-I

Without CONSULT

1. Start engine and warm it up to the 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 terminals under the following conditions.

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 conditions.

PBIB3458E

ECM

Condition

Voltage

Connector

+

–

Terminal

F52

57

59

Revving up to 4,000 rpm under 
no load at least 10 times

The voltage should be above 0.68 V at least once during 
this procedure.
The voltage should be below 0.18 V at least once during 
this procedure.

58

EC-244

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P0139, P0159 HO2S2

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 conditions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace malfunctioning heated oxygen sensor 2. Refer to 

EM-31, "Removal and Installation

(bank 2)"

, 

EM-33, "Removal and Installation (bank 1)"

.

ECM

Condition

Voltage

Connector

+

–

Terminal

F52

57

59

Keeping engine at idle for 10 min-
utes

The voltage should be above 0.68 V at least once during 
this procedure.
The voltage should be below 0.18 V at least once during 
this procedure.

58

ECM

Condition

Voltage

Connector

+

–

Terminal

F52

57

59

Coasting from 80 km/h (50 MPH) with 
selector lever in the D position

The voltage should be above 0.68 V at least once 
during this procedure.
The voltage should be below 0.18 V at least once dur-
ing this procedure.

58

P014C, P014D, P014E, P014F, P015A, P015B, P015C, P015D A/F SENSOR 1

EC-245

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

C

D

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P014C, P014D, P014E, P014F, P015A, P015B, P015C, P015D A/F SENSOR
1

DTC Logic

INFOID:0000000009178166

DTC DETECTION LOGIC

To judge malfunctions, this diagnosis measures response time of the A/F signal computed by ECM from the A/

F sensor 1 signal. The time is compensated by engine operating (speed and load), fuel feedback control con-

stant, and the A/F sensor 1 temperature index. Judgment is based on whether the compensated time (the A/F

signal cycling time index) is inordinately long or not.

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.

TESTING CONDITION:

Before performing the following procedure, confirm that battery voltage is more than 11 V at idle.
Do you have CONSULT?

YES

>> GO TO 2.

NO

>> GO TO 6.

2.

PERFORM DTC CONFIRMATION PROCEDURE-1

With CONSULT

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.

DTC No.

CONSULT screen terms

(Trouble diagnosis content)

DTC detecting condition

Possible Cause

P014C

A/F SENSOR1 (B1)
(O2 sensor slow response - rich 
to lean bank 1 sensor 1)

• The response time of a A/F sensor 1 signal 

delays more than the specified time com-
puted by ECM.

• Harness or connectors

(The A/F sensor 1 circuit is open or 
shorted.)

• A/F sensor 1

P014D

A/F SENSOR1 (B1)
(O2 sensor slow response - lean 
to rich bank 1 sensor 1)

P014E

A/F SENSOR1 (B2)
(O2 sensor slow response - rich 
to lean bank 2 sensor 1)

P014F

A/F SENSOR1 (B2)
(O2 sensor slow response - lean 
to rich bank 2 sensor 1)

P015A

A/F SENSOR1 (B1)
(O2 sensor delayed response - 
rich to lean bank 1 sensor 1)

P015B

A/F SENSOR1 (B1)
(O2 sensor delayed response - 
lean to rich bank 1 sensor 1)

P015C

A/F SENSOR1 (B2)
(O2 sensor delayed response - 
rich to lean bank 2 sensor 1)

P015D

A/F SENSOR1 (B2)
(O2 sensor delayed response - 
lean to rich bank 2 sensor 1)