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Nissan Pathfinder (2010 year). Manual - part 250

EC-92

< COMPONENT DIAGNOSIS >

[VQ40DE]

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

Check “A/F ALPHA-B1”, “A/F ALPHA-B2” for approximately 1 minute because they may fluctuate. It is NG

if the indication is out of the SP value even a little.

OK or NG

>> GO TO 17.

NG (Less than the SP value)>>GO TO 2.

NG (More than the SP value)>>GO TO 3.

CHECK “B/FUEL SCHDL”

Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” mode, and make sure that the indication is within the

SP value.
OK or NG

>> GO TO 4.

NG (More than the SP value)>>GO TO 19.

CHECK “B/FUEL SCHDL”

Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” mode, and make sure that the indication is within the

SP value.
OK or NG

>> GO TO 6.

NG (More than the SP value)>>GO TO 6.

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

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”

1. Stop the engine.

2. Disconnect PCV hose, and then plug it.

3. Start engine.

4. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that

each indication is within the SP value.

OK or NG

>> GO TO 5.

>> GO TO 6.

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-

ditions.

INSPECTION END

CHECK FUEL PRESSURE

Check fuel pressure. (Refer to

EC-495, "Fuel Pressure Check"

OK or NG

>> GO TO 9.

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

EC-495, "Fuel Pressure Check"

GO TO 8.

NG (Fuel pressure is too low)>>GO TO 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-403, "Description"

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

EC-89, "Diagnosis Procedure"

If OK, replace fuel pressure regulator.

2010 Pathfinder

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

EC-93

< COMPONENT DIAGNOSIS >

[VQ40DE]

>> GO TO 8.

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”

1. Start engine.

2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that

each indication is within the SP value.

OK or NG

INSPECTION END

>> GO TO 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

>> GO TO 12.

>> GO TO 10.

10.

DETECT MALFUNCTIONING PART

1. Check the following below

Ignition coil and its circuit (Refer to

EC-407, "Component Description"

Fuel injector and its circuit (Refer to

EC-399, "Component Description"

Intake air leakage

Low compression pressure (Refer to

EM-23, "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 “SPEC” of “DATA MONITOR” mode, and make sure that

each indication is within the SP value.

OK or NG

INSPECTION END

>> 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-149, "DTC Confirmation Procedure"

• For DTC P0131, P0151, refer to

EC-153, "DTC Confirmation Procedure"

• For DTC P0132, P0152, refer to

EC-157, "DTC Confirmation Procedure"

• For DTC P0133, P0153, refer to

EC-161, "DTC Confirmation Procedure"

• For DTC P2A00, P2A03, refer to

EC-385, "DTC Confirmation Procedure"

OK or NG

>> GO TO 15.

>> 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 “SPEC” of “DATA MONITOR” mode, and make sure that

each indication is within the SP value.

2010 Pathfinder

EC-94

< COMPONENT DIAGNOSIS >

[VQ40DE]

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

OK or NG

INSPECTION END

>> 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.

16.

CHECK “A/F ALPHA-B1”, “A/F ALPHA-B2”

1. Start engine.

2. Select “A/F ALPHA-B1”, “A/F ALPHA-B2” in “SPEC” of “DATA MONITOR” mode, and make sure that

each indication is within the SP value.

OK or NG

INSPECTION END

>> Detect malfunctioning part according to

EC-484, "Symptom Matrix Chart"

17.

CHECK “B/FUEL SCHDL”

Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” mode, and make sure that the indication is within the

SP value.
OK or NG

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

>> GO TO 21.

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

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 “SPEC” of “DATA MONITOR” mode, and

make sure that each indication is within the SP value.
OK or NG

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

2010 Pathfinder

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

EC-95

< COMPONENT DIAGNOSIS >

[VQ40DE]

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 “SPEC” of “DATA MONITOR” mode, and make sure that

each indication is within the SP value.

OK or NG

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

EC-118,

"Diagnosis Procedure"

2. GO TO 29.

>> GO TO 23.

23.

CHECK “MAS A/F SE-B1”

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

SP value.
OK or NG

>> 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

SEC-10, "ECM RE-COMMUNICATING FUNCTION : Special Repair Requirement"

(with Intelligent Key

system) or

SEC-124, "ECM RE-COMMUNICATING FUNCTION : Special Repair Requirement"

(without

Intelligent Key system).

3. Perform

EC-25, "VIN Registration"

4. Perform

EC-25, "Accelerator Pedal Released Position Learning"

5. Perform

EC-25, "Throttle Valve Closed Position Learning"

6. Perform

EC-25, "Idle Air Volume Learning"

>> GO TO 29.

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 in air cleaner element

• Uneven dirt in air cleaner element

• Improper specification in intake air system
OK or NG

>> GO TO 27.

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

26.

CHECK “B/FUEL SCHDL”

Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” mode, and make sure that the indication is within the

SP value.
OK or NG

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 “SPEC” of “DATA MONITOR” mode, and make sure that the indication is within the

SP value.
OK or NG

>> GO TO 28.

2010 Pathfinder

EC-96

< COMPONENT DIAGNOSIS >

[VQ40DE]

TROUBLE DIAGNOSIS - SPECIFICATION VALUE

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 in EVAP purge hose, stuck open of EVAP canister purge volume control solenoid

valve

• Malfunctioning seal in rocker cover gasket

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

• Malfunctioning seal in 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 “SPEC” of “DATA MONITOR” mode, and

make sure that each indication is within the SP value.
OK or NG

INSPECTION END

>> Detect malfunctioning part according to

EC-484, "Symptom Matrix Chart"

30.

CHECK “B/FUEL SCHDL”

Select “B/FUEL SCHDL” in “SPEC” of “DATA MONITOR” mode, and then make sure that the indication is

within the SP value.
OK or NG

INSPECTION END

>> Detect malfunctioning part according to

EC-484, "Symptom Matrix Chart"

2010 Pathfinder

POWER SUPPLY AND GROUND CIRCUIT

EC-97

< COMPONENT DIAGNOSIS >

[VQ40DE]

POWER SUPPLY AND GROUND CIRCUIT

Diagnosis Procedure

INFOID:0000000005257058

INSPECTION START

Start engine.

Is engine running?

Yes or No

Yes

>> GO TO 8.

>> GO TO 2.

CHECK ECM POWER SUPPLY CIRCUIT-I

1. Turn ignition switch OFF and then ON.

2. Check voltage between ECM terminal 109 and ground with

CONSULT-III or tester.

OK or NG

>> GO TO 4.

>> GO TO 3.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors M31, E152

• Fuse block (J/B) connector M4

• 10 A fuse (No.1)

• Harness for open or short between ECM and fuse

>> Repair harness or connectors.

CHECK GROUND CONNECTIONS

1. Turn ignition switch OFF.

2. Loosen and retighten three ground screws on the body. Refer to

EC-100, "Ground Inspection"

OK or NG

>> GO TO 5.

>> Repair or replace ground connections.

CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-I

1. Disconnect ECM harness connector.

2. Check harness continuity between ECM terminals 1, 115, 116 and ground.

Refer to Wiring Diagram.

Voltage: Battery voltage

MBIB0015E

BBIA0539E

Continuity should exist.

2010 Pathfinder

EC-98

< COMPONENT DIAGNOSIS >

[VQ40DE]

POWER SUPPLY AND GROUND CIRCUIT

3. Also check harness for short to power.
OK or NG

>> GO TO 7.

>> GO TO 6.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors F32, E2

• Harness for open or short between ECM and ground

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

CHECK ECM POWER SUPPLY CIRCUIT-II

1. Reconnect ECM harness connector.

2. Turn ignition switch ON.

3. Check voltage between IPDM E/R connector E119 terminal 3

and ground with CONSULT-III or tester.

OK or NG

>> Go to

EC-407, "Diagnosis Procedure"

>> GO TO 8.

CHECK ECM POWER SUPPLY CIRCUIT-III

1. Turn ignition switch OFF and wait at least 10 seconds.

2. Turn ignition switch ON and then OFF.

3. Check voltage between ECM terminals 119, 120 and ground

with CONSULT-III or tester.

OK or NG

>> GO TO 13.

NG (Battery voltage does not exist.)>>GO TO 9.

NG (Battery voltage exists for more than a few seconds.)>>GO TO

11.

CHECK ECM POWER SUPPLY CIRCUIT-IV

Check voltage between ECM terminal 111 and ground with CON-

SULT-III or tester.

OK or NG

>> GO TO 10.

>> GO TO 11.

10.

CHECK ECM POWER SUPPLY CIRCUIT-V

1. Disconnect ECM harness connector.

2. Disconnect IPDM E/R harness connector E119.

Voltage: Battery voltage

PBIB2569E

Voltage:

After turning ignition switch OFF, battery
voltage will exist for a few seconds, then to
drop approximately 0V.

PBIB1630E

Voltage: Battery voltage

PBIB1191E

2010 Pathfinder

POWER SUPPLY AND GROUND CIRCUIT

EC-99

< COMPONENT DIAGNOSIS >

[VQ40DE]

3. Check harness continuity between ECM terminals 119, 120 and IPDM E/R terminal 4.

Refer to Wiring Diagram.

4. Also check harness for short to ground and short to power.
OK or NG

>> GO TO 16.

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

11.

CHECK ECM POWER SUPPLY CIRCUIT-VI

1. Disconnect ECM harness connector.

2. Disconnect IPDM E/R harness connector E119.

3. Check harness continuity between ECM terminal 111 and IPDM E/R terminal 7.

Refer to Wiring Diagram.

4. Also check harness for short to ground and short to power.
OK or NG

>> GO TO 12.

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

12.

CHECK 20A FUSE

1. Disconnect 20 A fuse (No.53) from IPDM E/R.

2. Check 20 A fuse.
OK or NG

>> GO TO 16.

>> Replace 20A fuse.

13.

CHECK GROUND CONNECTIONS

Loosen and retighten three ground screws on the body. Refer to

EC-100, "Ground Inspection"

OK or NG

>> GO TO 14.

>> Repair or replace ground connections.

14.

CHECK ECM GROUND CIRCUIT FOR OPEN AND SHORT-II

1. Check harness continuity between ECM terminals 1, 115, 116 and ground.

Refer to Wiring Diagram.

2. Also check harness for short to power.
OK or NG

>> GO TO 16.

>> GO TO 15.

15.

DETECT MALFUNCTIONING PART

Check the following.

• Harness connectors F32, E2

Continuity should exist.

BBIA0539E

Continuity should exist.

2010 Pathfinder

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