INFINITI QX4 2005 Factory Service Manual

EC-80Revision: October 2005
BASIC SERVICE PROCEDURE
2005 QX56
OVERALL SEQUENCE
PBIB2086E

BASIC SERVICE PROCEDURE
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Revision: October 20052005 QX56
DETAILED PROCEDURE
1. INSPECTION START
1. Check service records for any recent repairs that may indicate a related malfunction, or a current need for
scheduled maintenance.
2. Open engine hood and check the following:
–Harness connectors for improper connections
–Wiring harness for improper connections, pinches and cut
–Vacuum hoses for splits, kinks and improper connections
–Hoses and ducts for leaks
–Air cleaner clogging
–Gasket
3. Confirm that electrical or mechanical loads are not applied.
–Head lamp switch is OFF.
–Air conditioner switch is OFF.
–Rear window defogger switch is OFF.
–Steering wheel is in the straight-ahead position, etc.
4. Start engine and warm it up until engine coolant temperature
indicator points the middle of gauge.
Ensure engine stays below 1,000 rpm.
5. Run engine at about 2,000 rpm for about 2 minutes under no
load.
6. Make sure that no DTC is displayed with CONSULT-II or GST.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2. REPAIR OR REPLACE
Repair or replace components as necessary according to corresponding Diagnostic Procedure.
>> GO TO 3.
SEF 9 83 U
SEF 9 76 U
SEF 9 77 U

EC-82Revision: October 2005
BASIC SERVICE PROCEDURE
2005 QX56
3. CHECK TARGET IDLE SPEED
With CONSULT-II
1. Run engine at about 2,000 rpm for about 2 minutes under no load.
2. Rev engine (2,000 to 3,000 rpm) 2 or 3 times under no load,
then run engine at idle speed for about 1 minute.
3. Read idle speed in “DATA MONITOR” mode with CONSULT-II.
Refer to EC-77, "
IDLE SPEED" .
Without CONSULT-II
1. Run engine at about 2,000 rpm for about 2 minutes under no load.
2. Rev engine (2,000 to 3,000 rpm) 2 or 3 times under no load, then run engine at idle speed for about 1
minute.
3. Check idle speed.
Refer to EC-77, "
IDLE SPEED" .
OK or NG
OK >> GO TO 10.
NG >> GO TO 4.
4. PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-90, "
Accelerator Pedal Released Position Learning" .
>> GO TO 5.
5. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-90, "
Throttle Valve Closed Position Learning" .
>> GO TO 6.
PBIA8513J
650 ± 50 rpm (in P or N position)
SEF 0 58 Y
650 ± 50 rpm (in P or N position)

BASIC SERVICE PROCEDURE
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6. PERFORM IDLE AIR VOLUME LEARNING
Perform EC-91, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes >> GO TO 7.
No >> 1. Follow the instruction of Idle Air Volume Learning.
2. GO TO 4.
7. CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Read idle speed in “DATA MONITOR” mode with CONSULT-II.
Refer to EC-77, "
IDLE SPEED" .
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
Refer to EC-77, "
IDLE SPEED" .
OK or NG
OK >> GO TO 10.
NG >> GO TO 8.
8. DETECT MALFUNCTIONING PART
Check the following.

Check camshaft position sensor (PHASE) and circuit. Refer to EC-291, "DTC P0340 CMP SENSOR
(PHASE)" .

Check crankshaft position sensor (POS) and circuit. Refer to EC-284, "DTC P0335 CKP SENSOR (POS)"
.
OK or NG
OK >> GO TO 9.
NG >> 1. Repair or replace.
2. GO TO 4.
9. CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but
this is a rare case.)
2. Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to
BL-139, "
ECM Re-communicating Function" .
>> GO TO 4. 650± 50 rpm (in P or N position)
650 ± 50 rpm (in P or N position)

EC-84Revision: October 2005
BASIC SERVICE PROCEDURE
2005 QX56
10. CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light.
Refer to EC-77, "
IGNITION TIMING" .
OK or NG
OK (With CONSULT-II)>>GO TO 19.
OK (With GST)>>GO TO 20.
NG >> GO TO 11.
11 . PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-90, "
Accelerator Pedal Released Position Learning" .
>> GO TO 12.
12. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-90, "
Throttle Valve Closed Position Learning" .
>> GO TO 13.
13. PERFORM IDLE AIR VOLUME LEARNING
Perform EC-91, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes >> GO TO 14.
No >> 1. Follow the instruction of Idle Air Volume Learning.
2. GO TO 4.
14. CHECK TARGET IDLE SPEED AGAIN
With CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Read idle speed in “DATA MONITOR” mode with CONSULT-II.
Refer to EC-77, "
IDLE SPEED" .
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed.
Refer to EC-77, "
IDLE SPEED" .
OK or NG
OK >> GO TO 15.
NG >> GO TO 17.15 ± 5° BTDC (in P or N position)
BBIA0379E
650 ± 50 rpm (in P or N position)
650 ± 50 rpm (in P or N position)

BASIC SERVICE PROCEDURE
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Revision: October 20052005 QX56
15. CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light.
Refer to EC-77, "
IGNITION TIMING" .
OK or NG
OK (With CONSULT-II)>>GO TO 19.
OK (Without CONSULT-II)>>GO TO 20.
NG >> GO TO 16.
16. CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-35, "
TIMING CHAIN" .
OK or NG
OK >> GO TO 17.
NG >> 1. Repair the timing chain installation.
2. GO TO 4.
17. DETECT MALFUNCTIONING PART
Check the following.

Check camshaft position sensor (PHASE) and circuit. Refer to EC-291, "DTC P0340 CMP SENSOR
(PHASE)" .

Check crankshaft position sensor (POS) and circuit. Refer to EC-284, "DTC P0335 CKP SENSOR (POS)"
.
OK or NG
OK >> GO TO 18.
NG >> 1. Repair or replace.
2. GO TO 4.
18. CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but
this is a rare case.)
2. Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to
BL-139, "
ECM Re-communicating Function" .
>> GO TO 4. 15 ± 5° BTDC (in P or N position)
BBIA0379E

EC-86Revision: October 2005
BASIC SERVICE PROCEDURE
2005 QX56
19. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With CONSULT-II
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30 MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 for 5 times.
6. Stop the vehicle and connect CONSULT-II to the vehicle.
7. Make sure that no (1st trip) DTC is displayed in “SELF-DIAG RESULTS” mode.
OK or NG
OK >>INSPECTION END
NG >> GO TO 21.
20. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With GST
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30 MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 for 5 times.
6. Stop the vehicle and connect GST to the vehicle.
7. Make sure that no (1st trip) DTC is displayed.
OK or NG
OK >>INSPECTION END
NG >> GO TO 21.

BASIC SERVICE PROCEDURE
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21. CHECK AIR FUEL RATIO (A/F) SENSOR 1 HARNESS
1. Turn ignition switch OFF and disconnect battery ground cable.
2. Disconnect ECM harness connector.
3. Disconnect A/F sensor 1 harness connector.
4. Check harness continuity between the following terminals.
Refer to EC-461, "
Wiring Diagram" .
5. Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 22.
NG >> 1. Repair open circuit or short to ground or short to power in harness or connectors.
2. GO TO 4.
22. PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Reconnect ECM harness connector.
2. Perform EC-90, "
Accelerator Pedal Released Position Learning" .
>> GO TO 23.
23. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-90, "
Throttle Valve Closed Position Learning" .
>> GO TO 24.
24. PERFORM IDLE AIR VOLUME LEARNING
Refer to EC-91, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Yes (With CONSULT-II)>>GO TO 25.
Yes (Without CONSULT-II)>>GO TO 26.
No >> 1. Follow the instruction of Idle Air Volume Learning.
2. GO TO 4.
A/F sensor 1 terminal ECM terminal
Bank1116
275
535
656
Bank 2176
277
557
658
Continuity should exist.

EC-88Revision: October 2005
BASIC SERVICE PROCEDURE
2005 QX56
25. CHECK CO%
With CONSULT-II
1. Start engine and warm it up until engine coolant temperature indicator points the middle of gauge.
2. Turn ignition switch OFF, wait at least 10 seconds and then turn ON.
3. Select “ENG COOLANT TEMP” in “ACTIVE TEST” mode.
4. Set “ENG COOLANT TEMP” to 5°C (41°F) by touching “DOWN”
and “Qd”.
5. Start engine and rev it (2,000 to 3,000 rpm) two or three times
under no load, then run engine at idle speed.
6. Check CO%.
OK or NG
OK >> GO TO 28.
NG >> GO TO 27.
26. CHECK CO%
Without CONSULT-II
1. Start engine and warm it up until engine coolant temperature indicator points to the middle of gauge.
2. Turn ignition switch OFF.
3. Disconnect engine coolant temperature sensor harness connector.
4. Connect a resistor (4.4 kΩ) between terminals of engine coolant
temperature sensor harness connector.
5. Start engine and rev it (2,000 to 3,000 rpm) two or three times
under no load, then run engine at idle speed.
6. Check CO%.
7. After checking CO%, turn ignition switch OFF, disconnect the
resistor from the terminals of engine coolant temperature sensor
harness connector, and then connect engine coolant tempera-
ture sensor harness connector to engine coolant temperature
sensor.
OK or NG
OK >> GO TO 28.
NG >> GO TO 27.
27. RECONNECT AIR FUEL RATIO (A/F) SENSOR 1 HARNESS CONNECTOR
1. Turn ignition switch OFF.
2. Reconnect A/F sensor 1 harness connector.
>> GO TO 31.
28. REPLACE AIR FUEL RATIO (A/F) SENSOR 1
1. Stop engine.
2. Replace A/F sensor 1 on the malfunctioning bank.
With CONSULT-II>>GO TO 29.
With GST>>GO TO 30.Idle CO: 3 − 11% and engine runs smoothly.
SEF 1 72 Y
Idle CO: 3 − 11% and engine runs smoothly.
SEF 9 82 UA

BASIC SERVICE PROCEDURE
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Revision: October 20052005 QX56
29. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With CONSULT-II
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30 MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 for 5 times.
6. Stop the vehicle and connect CONSULT-II to the vehicle.
7. Make sure that no (1st trip) DTC is displayed in “SELF-DIAG RESULTS” mode.
OK or NG
OK >> GO TO 4.
NG >> GO TO 31.
30. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With GST
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30 MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 for 5 times.
6. Stop the vehicle and connect GST to the vehicle.
7. Make sure that no (1st trip) DTC is displayed.
OK or NG
OK >> GO TO 4.
NG >> GO TO 31.
31. DETECT MALFUNCTIONING PART
Check the following.

Check fuel pressure regulator, and repair or replace if necessary. Refer to EC-93, "Fuel Pressure Check" .

Check mass air flow sensor and its circuit, and repair or replace if necessary. Refer to EC-174, "DTC
P0101 MAF SENSOR" and EC-183, "DTC P0102, P0103 MAF SENSOR" .

Check injector and its circuit, and repair or replace if necessary. Refer to EC-631, "INJECTOR CIRCUIT" .

Check engine coolant temperature sensor and its circuit, and repair or replace if necessary. Refer to EC-
195, "DTC P0117, P0118 ECT SENSOR" and EC-208, "DTC P0125 ECT SENSOR" .
OK or NG
OK >> GO TO 33.
NG >> 1. Repair or replace.
2. GO TO 32.