Diagnosis Procedure

WARNING: This page is about a different car, the 2012 Nissan Pathfinder. However, it is still accessible from the selected car via links, so may be relevant.

CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten ground screws on the body.
Refer to "GROUND INSPECTION ".

Fig 1: Checking Ground Connections
Courtesy of NISSAN NORTH AMERICA, INC.

OK or NG

OK: GO TO 2.

NG: Repair or replace ground connections.
RETIGHTEN AIR FUEL RATIO SENSOR 1 AND HEATED OXYGEN SENSOR 2
Loosen and retighten air fuel ratio (A/F) sensor 1 and heated oxygen senosr 2.

Refer to "REMOVAL AND INSTALLATION ".

GO TO 3.
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 4.
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.
OK or NG

OK: GO TO 5.

NG: Repair or replace.
CLEAR THE SELF-LEARNING DATA
With CONSULT
1. Start engine and warm it up to normal operating temperature.
2. Select "SELF-LEARNING CONT" in "WORK SUPPORT" mode with CONSULT.
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, P0172, P0174 or P0175 detected?
  
  Is it difficult to start engine?
  
  Without CONSULT
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor (1) harness connector.
  - : Vehicle front
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness connector.
6. Check that DTC P0102 is displayed.
7. Erase the DTC memory.
8. Check that DTC P0000 is displayed.
9. 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?
Fig 2: Identifying Mass Air Flow Sensor
Courtesy of NISSAN NORTH AMERICA, INC.

Yes or No

Yes: Perform trouble diagnosis for DTC P0171, P0174 or P0172, P0175. Refer to "DIAGNOSIS PROCEDURE " or "DIAGNOSIS PROCEDURE ".

No: GO TO 6.
CHECK HARNESS CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect A/F sensor 1 harness connector.
  
  Fig 3: Identifying A/F Sensor 1 Harness Connector
  Courtesy of NISSAN NORTH AMERICA, INC.
3. Check harness connector for water.
Water should not exit .

OK or NG

OK: GO TO 7.

NG: Repair or replace harness connector.
CHECK A/F SENSOR 1 POWER SUPPLY CIRCUIT
1. Turn ignition switch ON.
2. Check voltage between A/F sensor 1 terminal 4 and ground with CONSULT or tester.
Voltage: Battery voltage

OK or NG

OK: GO TO 9.

NG: GO TO 8.

Fig 4: Checking Voltage Between A/F Sensor 1 Harness Connector Terminal 4 And Ground Using Tester
Courtesy of NISSAN NORTH AMERICA, INC.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E5, F14
- IPDM E/R harness connector E119
- 15 A fuse (No. 54)
- Harness for open or short between A/F sensor 1 and IPDM E/R
Repair or replace harness or connectors.

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

Turn ignition switch OFF.
Disconnect ECM harness connector.

Check harness continuity between A/F sensor 1 terminals and ECM terminals as per the following.

Refer to WIRING DIAGRAM .

	A/F sensor 1 terminal	ECM terminal
Bank1	1	35
Bank1	2	56
Bank 2	1	16
Bank 2	2	75

Continuity should exist .

Check harness continuity between the following terminals and ground.

Refer to WIRING DIAGRAM .

Bank 1		Bank 2
A/F sensor 1 terminal	ECM terminal	A/F sensor 1 terminal	ECM terminal
1	35	1	16
2	56	2	75

Continuity should not exist .

Also check harness for short to power.

OK or NG

OK: GO TO 10.

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

CHECK A/F SENSOR 1 HEATER
Refer to "COMPONENT INSPECTION ".

OK or NG

OK: GO TO 11.

NG: GO TO 13.
CHECK HEATED OXYGEN SENSOR 2
Check heated oxygen sensor 2. Refer to "COMPONENT INSPECTION ".

Is the inspection result normal?

YES: GO TO 12.

NO: Replace malfunctioning heated oxygen sensor 2.
CHECK INTERMITTENT INCIDENT
Refer to "INTERMITTENT INCIDENT ".

OK or NG

OK: GO TO 13.

NG: Repair or replace.
REPLACE A/F SENSOR 1
Replace malfunctioning A/F sensor 1. Refer to EXHAUST MANIFOLD AND THREE WAY CATALYST .
CAUTION:
- Discard any A/F 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 A/F 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).
GO TO 14.
CONFIRM A/F ADJUSTMENT DATA
1. Turn ignition switch OFF and then ON.
2. Select "A/F ADJ-B1" and "A/F ADJ-B2" in "DATA MONITOR" mode with CONSULT.
3. Make sure that "0.000" is displayed on CONSULT screen.
OK or NG

OK: INSPECTION END

NG: GO TO 15.
CLEAR THE SELF-LEARNING DATA
With CONSULT
1. Start engine and warm it up to normal operating temperature.
2. Select "SELF-LEARNING CONT" in "WORK SUPPORT" mode with CONSULT.
3. Clear the self-learning control coefficient by touching "CLEAR".
Without CONSULT
1. Start engine and warm it up to normal operating temperature.
2. Turn ignition switch OFF.
3. Disconnect mass air flow sensor (1) harness connector.
  - : Vehicle front
4. Restart engine and let it idle for at least 5 seconds.
5. Stop engine and reconnect mass air flow sensor harness connector.
6. Check that DTC P0102 is displayed.
7. Erase the DTC memory.
8. Check that DTC P0000 is displayed.
GO TO 16.

Fig 5: Identifying Mass Air Flow Sensor
Courtesy of NISSAN NORTH AMERICA, INC.
CONFIRM A/F ADJUSTMENT DATA
1. Turn ignition switch OFF and then ON.
2. Select "A/F ADJ-B1" and "A/F ADJ-B2" in "DATA MONITOR" mode with CONSULT.
3. Check that "0.000" is displayed on CONSULT screen.
>> INSPECTION END