Nissan Pathfinder. Manual - part 522

EC-394

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P1805 BRAKE SWITCH

3. Also check harness for short to ground and short to power.
Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace error-detected parts.

4.

CHECK STOP LAMP SWITCH

Check stop lamp switch. Refer to 

EC-384, "Component Inspection (Stop Lamp Switch)"

.

Is the inspection result normal?

YES

>> Check intermittent incident. Refer to 

GI-49, "Intermittent Incident"

.

NO

>> Replace stop lamp switch. Refer to 

BR-20, "Removal and Installation"

.

Component Inspection (Stop Lamp Switch)

INFOID:0000000009178320

1.

CHECK STOP LAMP SWITCH-I

1. Turn ignition switch OFF.

2. Disconnect stop lamp switch harness connector.

3. Check harness continuity between stop lamp switch terminals under the following conditions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> GO TO 2.

2.

CHECK STOP LAMP SWITCH-II

1. Adjust stop lamp switch installation. Refer to 

BR-15, "Adjustment"

.

2. Check harness continuity between stop lamp switch terminals under the following conditions.

Is the inspection result normal?

YES

>> INSPECTION END

NO

>> Replace stop lamp switch. Refer to 

BR-20, "Removal and Installation"

.

Stop lamp switch

ECM

Continuity

Connector

Terminal

Connector

Terminal

E38

2

E16

122

Existed

Terminals

Condition

Continuity

1 and 2

Brake pedal

Fully released

Not existed

Slightly depressed

Existed

Terminals

Condition

Continuity

1 and 2

Brake pedal

Fully released

Not existed

Slightly depressed

Existed

P2096, P2097, P2098, P2099 A/F SENSOR 1

EC-395

< DTC/CIRCUIT DIAGNOSIS >

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P2096, P2097, P2098, P2099 A/F SENSOR 1

DTC Logic

INFOID:0000000009178321

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following before conduct-

ing 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.

>> GO TO 2.

2.

PERFORM DTC CONFIRMATION PROCEDURE

1. Clear the mixture ratio self-learning value. Refer to 

EC-145, "Work Procedure"

.

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

6. Let engine idle for 1 minute.

7. Keep engine speed between 2,500 and 3,000 rpm for 20 minutes.

8. Check 1st trip DTC.
Is 1st trip DTC detected?

YES

>> Proceed to 

EC-396, "Diagnosis Procedure"

.

NO

>> INSPECTION END

Diagnosis Procedure

INFOID:0000000009178322

1.

RETIGHTEN A/F SENSOR 1 AND HEATED OXYGEN SENSOR 2

Loosen and retighten the A/F sensor 1 and heated oxygen sensor 2. Refer to 

EM-31, "Removal and Installa-

tion (bank 2)"

, 

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

.

>> GO TO 2.

DTC No.

Trouble diagnosis name

(Trouble diagnosis content)

DTC detecting condition

Possible Cause

P2096

POST CAT FUEL TRIM SYS 
B1
(Post catalyst fuel trim system 
too lean bank 1)

The output voltage computed by ECM from the A/
F sensor 1 signal is shifts to the lean side for a 
specified period.

• A/F sensor 1 (bank 1)
• A/F sensor 1 heater
• Heated oxygen sensor 2 (bank 1)
• Fuel pressure
• Fuel injector
• Intake air leaks
• Exhaust gas leaks

P2097

POST CAT FUEL TRIM SYS 
B1
(Post catalyst fuel trim system 
too rich bank 1)

The A/F signal computed by ECM from the A/F 
sensor 1 signal is shifts to the rich side for a spec-
ified period.

P2098

POST CAT FUEL TRIM SYS 
B2
(Post catalyst fuel trim system 
too lean bank 2)

The output voltage computed by ECM from the A/
F sensor 1 signal is shifts to the lean side for a 
specified period.

• A/F sensor 1 (bank 2)
• A/F sensor 1 heater
• Heated oxygen sensor 2 (bank 2)
• Fuel pressure
• Fuel injector
• Intake air leaks
• Exhaust gas leaks

P2099

POST CAT FUEL TRIM SYS 
B2
(Post catalyst fuel trim system 
too rich bank 2)

The A/F signal computed by ECM from the A/F 
sensor 1 signal is shifts to the rich side for a spec-
ified period.

EC-396

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

P2096, P2097, P2098, P2099 A/F SENSOR 1

2.

CHECK FOR EXHAUST GAS LEAK

1. Start engine and run it at idle.

2. Listen for an exhaust gas leak before the three way catalyst 2.
Is exhaust gas leak detected?

YES

>> Repair or replace.

NO

>> GO TO 3.

3.

CHECK FOR INTAKE AIR LEAKAGE

1. Start engine and run it at idle.

2. Listen for an intake air leakage after the mass air flow sensor.
Is intake air leakage detected?

YES

>> GO TO 4.

NO

>> Repair or replace malfunctioning part.

4.

CLEAR THE MIXTURE RATIO SELF-LEARNING VALUE

1. Clear the mixture ratio self-learning value. Refer to 

EC-145, "Work Procedure"

.

2. 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?

YES

>> Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to 

EC-252, "DTC Logic"

or 

EC-256, "DTC Logic"

.

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.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair or replace harness connector.

6.

CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY

1. Disconnect A/F sensor 1 harness connector.

2. Turn ignition switch ON.

3. Check the voltage between A/F sensor 1 harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 8.

NO

>> GO TO 7.

7.

CHECK AIR FUEL RATIO (A/F) SENSOR 1 POWER SUPPLY CIRCUIT

1. Turn ignition switch OFF.

2. Disconnect IPDM E/R harness connector.

3. Check the continuity between A/F sensor 1 harness connector and IPDM E/R harness connector.

Water should not exit.

DTC

A/F sensor

Ground

Voltage (V)

Bank

Connector

Terminal

P2096
P2097

1

F5

4

Ground

Battery voltage

P2098
P2099

2

F65

4

P2096, P2097, P2098, P2099 A/F SENSOR 1

EC-397

< DTC/CIRCUIT DIAGNOSIS >

[VQ35DE]

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EC

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Is the inspection result normal?

YES

>> Perform the trouble diagnosis for power supply circuit.

NO

>> Repair or replace error-detected parts.

8.

CHECK A/F SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT

1. Turn ignition switch OFF.

2. Disconnect ECM harness connector.

3. Check the continuity between A/F sensor 1 harness connector and ECM harness connector.

4. Check the continuity between A/F sensor 1 harness connector and ground, or ECM harness connector

and ground.

5. Also check harness for short to power.
Is the inspection result normal?

YES

>> GO TO 9.

NO

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

9.

CHECK A/F SENSOR 1 HEATER

Check A/F sensor 1 heater. Refer to 

EC-184, "Component Inspection"

.

Is the inspection result normal?

YES

>> GO TO 10.

NO

>> GO TO 12.

10.

CHECK HEATED OXYGEN SENSOR 2

Check heated oxygen sensor 2. Refer to 

EC-187, "Component Inspection"

.

DTC

A/F sensor 1

IPDM E/R 

Continuity

Bank

Connector

Terminal

Connector

Terminal

P2096
P2097

1

F5

4

F19

52

Existed

P2098
P2099

2

F65

4

53

DTC

A/F sensor 1

ECM

Continuity

Bank

Connector

Terminal

Connector

Terminal

P2096
P2097

1

F5

1

F52

69

Existed

2

73

P2098
P2099

2

F65

1

77

2

81

DTC

A/F sensor 1

Ground

Continuity

Bank

Connector

Terminal

P2096
P2097

1

F5

1

Ground

Not existed

2

P2098
P2099

2

F65

1

2

DTC

ECM

Ground

Continuity

Connector

Terminal

P2096
P2097

F52

69

Ground

Not existed

73

P2098
P2099

77

81