Diagnosis Procedure

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

Fig 1: Identifying Body Ground (M70 And M16)
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG

OK: GO TO 2.

NG: Repair or replace ground connections.
RETIGHTEN AIR FUEL RATIO (A/F) SENSOR 1
1. Loosen and retighten the air fuel ratio (A/F) sensor 1.
Fig 2: Identifying Air Fuel Ratio (A/F) Sensor 1
Courtesy of NISSAN MOTOR CO., U.S.A.

Tightening torque: 50 N-m (5.1 kg-m, 37 ft-lb)

GO TO 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.
OK or NG

OK: GO TO 4.

NG: Repair or replace malfunctioning part.
CLEAR THE SELF-LEARNING DATA
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select "SELF-LEARNING CONT" in "WORK SUPPORT" mode with CONSULT-III.
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-III
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.
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. Refer to "How to Erase DTC" in "EMISSION-RELATED DIAGNOSTIC INFORMATION ".
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 3: Identifying Mass Air Flow (MAF) Sensor
Courtesy of NISSAN MOTOR CO., U.S.A.

Yes or No

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

No: GO TO 5.
CHECK HARNESS CONNECTOR
1. Turn ignition switch OFF.
2. Disconnect A/F sensor 1 harness connector.
  
  Fig 4: Identifying A/F Sensor 1 Harness Connector
  Courtesy of NISSAN MOTOR CO., U.S.A.
3. Check harness connector for water.
Water should not exit .

OK or NG

OK: GO TO 6.

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 3 and ground with CONSULT-III or tester.
Voltage: Battery voltage

OK or NG

OK: GO TO 8.

NG: GO TO 7.

Fig 5: Checking Voltage Between A/F Sensor 1 Terminal 3 And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.
DETECT MALFUNCTIONING PART
Check the following.
- Harness connectors E12, F3
- IPDM E/R harness connector E7
- 15 A fuse
- Harness for open or short between A/F sensor 1 and fuse
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 terminal and ECM terminal as per the following.

Refer to SYSTEM WIRING DIAGRAMS article.

ECM CONNECTOR TERMINALS REFERENCE CHART

	A/F sensor 1 terminal	ECM terminal
Bank1	1	16
	2	75
	5	35
	6	56
Bank 2	1	76
	2	77
	5	57
	6	58

Continuity should exist .

Check harness continuity between the following terminals and ground.

Refer to SYSTEM WIRING DIAGRAMS article.

ECM CONNECTOR TERMINALS REFERENCE CHART

Bank 1		Bank 2
A/F sensor 1 terminal	ECM terminal	A/F sensor 1 terminal	ECM terminal
1	16	1	76
2	75	2	77
5	35	5	57
6	56	6	58

Continuity should not exist .

Also check harness for short to power.

OK or NG

OK: GO TO 9.

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 10.

NG: GO TO 11.
CHECK INTERMITTENT INCIDENT
Perform "DIAGNOSIS PROCEDURE ".

OK or NG

OK: GO TO 11.

NG: Repair or replace malfunctioning part.
REPLACE AIR FUEL RATIO (A/F) SENSOR 1
Replace malfunctioning air fuel ratio (A/F) sensor 1.
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 12.
CONFIRM A/F ADJUSTMENT DATA
1. Turn ignition switch ON.
2. Select "A/F ADJ-B1" and "A/F ADJ-B2" in "DATA MONITOR" mode with CONSULT-III.
3. Check that that "0.000" is displayed on CONSULT-III screen.
OK or NG

OK: INSPECTION END

NG: GO TO 13.
CLEAR A/F ADJUSTMENT DATA
With CONSULT-III
1. Start engine and warm it up to normal operating temperature.
2. Select "SELF-LEARNING CONT" in "WORK SUPPORT" mode with CONSULT-III.
3. Clear the self-learning control coefficient by touching "CLEAR".
Without CONSULT-III
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.
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. Refer to "How to Erase DTC" in "EMISSION-RELATED DIAGNOSTIC INFORMATION ".
8. Check that DTC P0000 is displayed.
GO TO 14.

Fig 6: Identifying Mass Air Flow (MAF) Sensor
Courtesy of NISSAN MOTOR CO., U.S.A.
CONFIRM A/F ADJUSTMENT DATA

Turn ignition switch OFF and then ON.
Select "A/F ADJ-B1" and "A/F ADJ-B2" in "DATA MONITOR" mode with CONSULT-III.
Check that that "0.000" is displayed on CONSULT-III screen.

INSPECTION END