Nissan Pathfinder (2007 year). Manual - part 159

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

EC-139

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2007 Pathfinder

5. 

CHANGE ENGINE OIL

1.

Stop the engine.

2.

Change engine oil.

NOTE:
This symptom may occur when a large amount of gasoline is mixed with engine oil because of driving
conditions (such as when engine oil temperature does not rise enough since a journey distance is too
short during winter). The symptom will not be detected after changing engine oil or changing driving con-
dition.

>> INSPECTION END

6. 

CHECK FUEL PRESSURE

Check fuel pressure. (Refer to 

EC-79, "Fuel Pressure Check"

  .)

OK or NG

OK

>> GO TO 9.

NG (Fuel pressure is too high)>>Replace fuel pressure regulator, refer to 

EC-79

  . GO TO 8.

NG (Fuel pressure is too low)>>GO TO 7.

7. 

DETECT MALFUNCTIONING PART

1.

Check the following.

–

Clogged and bent fuel hose and fuel tube

–

Clogged fuel filter

–

Fuel pump and its circuit (Refer to 

EC-637

  .)

2.

If NG, repair or replace the malfunctioning part. (Refer to 

EC-79

  .)

If OK, replace fuel pressure regulator.

>> GO TO 8.

8. 

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”

1.

Start engine.

2.

Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “DATA MONITOR (SPEC)” mode, and make sure that the
each indication is within the SP value.

OK or NG

OK

>> INSPECTION END

NG

>> GO TO 9.

9. 

PERFORM POWER BALANCE TEST

1.

Perform “POWER BALANCE” in “ACTIVE TEST” mode.

2.

Make sure that the each cylinder produces a momentary engine
speed drop.

OK or NG

OK

>> GO TO 12.

NG

>> GO TO 10.

PBIB0133E

EC-140

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

2007 Pathfinder

10. 

DETECT MALFUNCTIONING PART

1.

Check the following.

–

Ignition coil and its circuit (Refer to 

EC-643

  .)

–

Fuel injector and its circuit (Refer to 

EC-630

  .)

–

Intake air leakage

–

Low compression pressure (Refer to 

EM-92, "CHECKING COMPRESSION PRESSURE"

  .)

2.

If NG, repair or replace the malfunctioning part.
If OK, replace fuel injector. (It may be caused by leakage from fuel injector or clogging.)

>> GO TO 11.

11. 

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”

1.

Start engine.

2.

Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “DATA MONITOR (SPEC)” mode, and make sure that the
each indication is within the SP value.

OK or NG

OK

>> INSPECTION END

NG

>> GO TO 12.

12. 

CHECK A/F SENSOR 1 FUNCTION

Perform all DTC Confirmation Procedure related with A/F sensor 1.

●

For DTC P0130, P0150, refer to 

EC-228, "DTC Confirmation Procedure"

  .

●

For DTC P0131, P0151, refer to 

EC-237, "DTC Confirmation Procedure"

  .

●

For DTC P0132, P0152, refer to 

EC-245, "DTC Confirmation Procedure"

  .

●

For DTC P0133, P0153, refer to 

EC-254, "DTC Confirmation Procedure"

  .

●

For DTC P2A00, P2A03, refer to 

EC-606, "DTC Confirmation Procedure"

  .

OK or NG

OK

>> GO TO 15.

NG

>> GO TO 13.

13. 

CHECK A/F SENSOR 1 CIRCUIT

Perform Diagnostic Procedure according to corresponding DTC.

>> GO TO 14.

14. 

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”

1.

Start engine.

2.

Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “DATA MONITOR (SPEC)” mode, and make sure that the
each indication is within the SP value.

OK or NG

OK

>> INSPECTION END

NG

>> GO TO 15.

15. 

DISCONNECT AND RECONNECT ECM HARNESS CONNECTOR

1.

Stop the engine.

2.

Disconnect ECM harness connector. Check pin terminal and connector for damage, and then reconnect it.

>> GO TO 16.

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

EC-141

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EC

2007 Pathfinder

16. 

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”

1.

Start engine.

2.

Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “DATA MONITOR (SPEC)” mode, and make sure that the
each indication is within the SP value.

OK or NG

OK

>> INSPECTION END

NG

>> Detect malfunctioning part according to 

EC-91, "Symptom Matrix Chart"

  .

17. 

CHECK “B/FUEL SCHDL”

Select “B/FUEL SCHDL” in “DATA MONITOR (SPEC)” mode, and
make sure that the indication is within the SP value.

OK or NG

OK

>> INSPECTION END

NG (More than the SP value)>>GO TO 18.
NG (Less than the SP value)>>GO TO 25.

18. 

DETECT MALFUNCTIONING PART

1.

Check for the cause of large engine friction. Refer to the following.

–

Engine oil level is too high

–

Engine oil viscosity

–

Belt tension of power steering, alternator, A/C compressor, etc. is excessive

–

Noise from engine

–

Noise from transmission, etc.

2.

Check for the cause of insufficient combustion. Refer to the following.

–

Valve clearance malfunction

–

Intake valve timing control function malfunction

–

Camshaft sprocket installation malfunction, etc.

>> Repair or replace malfunctioning part, and then GO TO 30.

19. 

CHECK INTAKE SYSTEM

Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.

●

Crushed air ducts

●

Malfunctioning seal of air cleaner element

●

Uneven dirt of air cleaner element

●

Improper specification of intake air system

OK or NG

OK

>> GO TO 21.

NG

>> Repair or replace malfunctioning part, and then GO TO 20.

PBIB2332E

EC-142

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

2007 Pathfinder

20. 

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”, AND “B/FUEL SCHDL”

Select “A/F ALPHA-B1”, “A/F ALPHA-B2”, and “B/FUEL SCHDL” in “DATA MONITOR (SPEC)” mode, and
make sure that the each indication is within the SP value.

OK or NG

OK

>> INSPECTION END

NG (“B/FUEL SCHDL” is more, “A/F ALPHA-B1”, “A/F ALPHA-B2” are less than the SP value)>>GO TO 21.

21. 

DISCONNECT AND RECONNECT MASS AIR FLOW SENSOR HARNESS CONNECTOR

1.

Stop the engine.

2.

Disconnect mass air flow sensor harness connector. Check pin terminal and connector for damage and
then reconnect it again.

>> GO TO 22.

22. 

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”

1.

Start engine.

2.

Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “DATA MONITOR (SPEC)” mode, and make sure that the
each indication is within the SP value.

OK or NG

OK

>> 1. Detect malfunctioning part of mass air flow sensor circuit and repair it. Refer to 

EC-196

  .

2. GO TO 29.

NG

>> GO TO 23.

23. 

CHECK “MAS A/F SE-B1”

Select “MAS A/F SE-B1” in “DATA MONITOR (SPEC)” mode, and
make sure that the indication is within the SP value.

OK or NG

OK

>> GO TO 24.

NG (More than the SP value)>>Replace mass air  flow  sensor,  and

then GO TO 29.

24. 

REPLACE ECM

1.

Replace ECM.

2.

Perform initialization of NVIS(NATS) system and registration of all NVIS(NATS) ignition key IDs. Refer to

BL-96, "ECM Re-communicating Function"

  .

3.

Perform 

EC-76, "VIN Registration"

  .

4.

Perform 

EC-77, "Accelerator Pedal Released Position Learning"

  .

5.

Perform 

EC-77, "Throttle Valve Closed Position Learning"

  .

6.

Perform 

EC-77, "Idle Air Volume Learning"

  .

>> GO TO 29.

PBIB2370E

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

EC-143

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EC

2007 Pathfinder

25. 

CHECK INTAKE SYSTEM

Check for the cause of uneven air flow through mass air flow sensor. Refer to the following.

●

Crushed air ducts

●

Malfunctioning seal of air cleaner element

●

Uneven dirt of air cleaner element

●

Improper specification of intake air system

OK or NG

OK

>> GO TO 27.

NG

>> Repair or replace malfunctioning part, and then GO TO 26.

26. 

CHECK “B/FUEL SCHDL”

Select “B/FUEL SCHDL” in “DATA MONITOR (SPEC)” mode, and make sure that the indication is within the
SP value.

OK or NG

OK

>> INSPECTION END

NG (Less than the SP value)>>GO TO 27.

27. 

CHECK “MAS A/F SE-B1”

Select “MAS A/F SE-B1” in “DATA MONITOR (SPEC)” mode, and
make sure that the indication is within the SP value.

OK or NG

OK

>> GO TO 28.

NG (Less than the SP value)>>Replace mass air flow sensor, and

then GO TO 30.

28. 

CHECK INTAKE SYSTEM

Check for the cause of air leak after the mass air flow sensor. Refer to the following.

●

Disconnection, looseness, and cracks in air duct

●

Looseness of oil filler cap

●

Disconnection of oil level gauge

●

Open stuck, breakage, hose disconnection, or cracks of PCV valve

●

Disconnection or cracks of EVAP purge hose, open stuck of EVAP canister purge volume control solenoid
valve

●

Malfunctioning seal of rocker cover gasket

●

Disconnection, looseness, or cracks of hoses, such as vacuum hose, connecting to intake air system
parts

●

Malfunctioning seal of intake air system, etc.

>> GO TO 30.

29. 

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”, AND “B/FUEL SCHDL”

Select “A/F ALPHA-B1”, “A/F ALPHA-B2”, and “B/FUEL SCHDL” in “DATA MONITOR (SPEC)” mode, and
make sure that the each indication is within the SP value. 

OK or NG

OK

>> INSPECTION END

NG

>> Detect malfunctioning part according to 

EC-91, "Symptom Matrix Chart"

  .

PBIB2370E

EC-144

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

2007 Pathfinder

30. 

CHECK “B/FUEL SCHDL”

Select “B/FUEL SCHDL” in “DATA MONITOR (SPEC)” mode, and then make sure that the indication is within
the SP value.

OK or NG

OK

>> INSPECTION END

NG

>> Detect malfunctioning part according to 

EC-91, "Symptom Matrix Chart"

  .

TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT

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2007 Pathfinder

TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT

PFP:00006

Description

UBS00K4K

Intermittent incidents may occur. In many cases, the malfunction resolves itself (the part or circuit function
returns to normal without intervention). It is important to realize that the symptoms described in the customer's
complaint often do not recur on (1st trip) DTC visits. Realize also that the most frequent cause of intermittent
incidents occurrences is poor electrical connections. Because of this, the conditions under which the incident
occurred may not be clear. Therefore, circuit checks made as part of the standard diagnostic procedure may
not indicate the specific malfunctioning area.

Common Intermittent Incidents Report Situations

Diagnostic Procedure

UBS00K4L

1. 

INSPECTION START

Erase (1st trip) DTCs. Refer to 

EC-60, "HOW TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMA-

TION"

  .

>> GO TO 2.

2. 

CHECK GROUND TERMINALS

Check ground terminals for corroding or loose connection.
Refer to 

EC-153, "Ground Inspection"

  .

OK or NG

OK

>> GO TO 3.

NG

>> Repair or replace.

3. 

SEARCH FOR ELECTRICAL INCIDENT

Perform 

GI-27, "How to Perform Efficient Diagnosis for an Electrical Incident"

  , “INCIDENT SIMULATION

TESTS”.

OK or NG

OK

>> GO TO 4.

NG

>> Repair or replace.

4. 

CHECK CONNECTOR TERMINALS

Refer to 

GI-24, "How to Check Terminal"

  , “HOW TO PROBE CONNECTORS”, “How to Check Enlarged Con-

tact Spring of Terminal”.

OK or NG

OK

>> INSPECTION END

NG

>> Repair or replace connector.

STEP in Work Flow

Situation

2

The CONSULT-II is used. The SELF-DIAG RESULTS screen shows time data other than [0] or [1t].

3 or 4

The symptom described by the customer does not recur.

5

(1st trip) DTC does not appear during the DTC Confirmation Procedure.

10

The Diagnostic Procedure for PXXXX does not indicate the malfunctioning area.

EC-146

POWER SUPPLY AND GROUND CIRCUIT

2007 Pathfinder

POWER SUPPLY AND GROUND CIRCUIT

PFP:24110

Wiring Diagram

UBS00K4M

BBWA2358E