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EC-68Revision: November 2009
ON BOARD DIAGNOSTIC (OBD) SYSTEM
2006 QX56
EXPLANATION FOR DRIVING PATTERNS FOR “MISFIRE
TION>”, “FUEL INJECTION SYSTEM”
Driving pattern B means the vehicle operation as follows:
All components and systems should be monitored at least once by the OBD system.
The B counter will be cleared when the malfunction is detected once regardless of the driving pattern.
The B counter will be counted up when driving pattern B is satisfied without any malfunction.
The MIL will go off when the B counter reaches 3. (*2 in “OBD SYSTEM OPERATION CHART”)
Driving pattern C means the vehicle operation as follows:
The following conditions should be satisfied at the same time:
Engine speed: (Engine speed in the freeze frame data) ±375 rpm
Calculated load value: (Calculated load value in the freeze frame data) x (1± 0.1) [%]
Engine coolant temperature (T) condition:
When the freeze frame data shows lower than 70 °C (158 °F), T should be lower than 70 °C (158 °F).
When the freeze frame data shows higher than or equal to 70 °C (158 °F), T should be higher than or equal
to 70 °C (158 °F).
Example:
If the stored freeze frame data is as follows:
Engine speed: 850 rpm, Calculated load value: 30%, Engine coolant temperature: 80 °C (176 °F)
To be satisfied with driving pattern C, the vehicle should run under the following conditions:
Engine speed: 475 - 1,225 rpm, Calculated load value: 27 - 33%, Engine coolant temperature: more than 70 °C
(158 °F)
The C counter will be cleared when the malfunction is detected regardless of vehicle conditions above.
The C counter will be counted up when vehicle conditions above is satisfied without the same malfunction.
The DTC will not be displayed after C counter reaches 80.
The 1st trip DTC will be cleared when C counter is counted once without the same malfunction after DTC
is stored in ECM.
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BASIC SERVICE PROCEDUREEC-71
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BASIC SERVICE PROCEDUREPFP:00018
Basic InspectionUBS00KZU
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.
–Headlamp 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.
SEF983U
SEF976U
SEF977U
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EC-72Revision: November 2009
BASIC SERVICE PROCEDURE
2006 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) two or three 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-76, "
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) two or three times under no load, then run engine at idle speed for about 1 minute.
3. Check idle speed. Refer to EC-76, "
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-78, "
Accelerator Pedal Released Position Learning" .
>> GO TO 5.
5. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-78, "
Throttle Valve Closed Position Learning" .
>> GO TO 6.
PBIA8513J
650 ± 50 rpm (in P or N position)
SEF058Y
650 ± 50 rpm (in P or N position)
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BASIC SERVICE PROCEDUREEC-73
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6. PERFORM IDLE AIR VOLUME LEARNING
Refer to EC-78, "
Idle Air Volume Learning" .
Is Idle Air Volume Learning carried out successfully?
Ye s o r N o
Ye s > > G O T O 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-76, "
IDLE SPEED" .
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. Refer to EC-76, "
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-347, "DTC P0340 CMP SENSOR
(PHASE)" .
Check crankshaft position sensor (POS) and circuit. Refer to EC-340, "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)
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EC-74Revision: November 2009
BASIC SERVICE PROCEDURE
2006 QX56
10. CHECK IGNITION TIMING
1. Run engine at idle.
2. Check ignition timing with a timing light. Refer to EC-76, "
IGNITION TIMING" .
OK or NG
OK >> GO TO 19.
NG >> GO TO 11.
11 . PERFORM ACCELERATOR PEDAL RELEASED POSITION LEARNING
1. Stop engine.
2. Perform EC-78, "
Accelerator Pedal Released Position Learning" .
>> GO TO 12.
12. PERFORM THROTTLE VALVE CLOSED POSITION LEARNING
Perform EC-78, "
Throttle Valve Closed Position Learning" .
>> GO TO 13.
13. PERFORM IDLE AIR VOLUME LEARNING
Refer to EC-78, "
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-76, "
IDLE SPEED" .
Without CONSULT-II
1. Start engine and warm it up to normal operating temperature.
2. Check idle speed. Refer to EC-76, "
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)
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BASIC SERVICE PROCEDUREEC-75
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15. CHECK IGNITION TIMING AGAIN
1. Run engine at idle.
2. Check ignition timing with a timing light. Refer to EC-76, "
IGNITION TIMING" .
OK or NG
OK >> GO TO 19.
NG >> GO TO 16.
16. CHECK TIMING CHAIN INSTALLATION
Check timing chain installation. Refer to EM-37, "
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-347, "DTC P0340 CMP SENSOR
(PHASE)" .
Check crankshaft position sensor (POS) and circuit. Refer to EC-340, "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.
19. INSPECTION END
Did you replace ECM, referring this Basic Inspection procedure?
Ye s o r N o
Ye s > > 1 . P e r f o r m EC-77, "VIN Registration" .
2. INSPECTION END
No >> INSPECTION END
15
± 5 ° BTDC (in P or N position)
BBIA0379E
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2. Connect ignition coil No.1 and spark plug with suitable high-ten-
sion wire as shown, and attach timing light clamp to this wire.
3. Check ignition timing.
VIN RegistrationUBS00KZX
DESCRIPTION
VIN Registration is an operation to registering VIN in ECM. It must be performed each time ECM is replaced.
NOTE:
Accurate VIN which is registered in ECM may be required for Inspection & Maintenance (I/M).
OPERATION PROCEDURE With CONSULT-II
1. Check the VIN of the vehicle and note it. Refer to GI-47, "IDENTIFICATION INFORMATION" .
2. Turn ignition switch ON and engine stopped.
3. Select “VIN REGISTRATION ” in “WORK SUPPORT ” mode.
4. Follow the instruction of CONSULT-II display.
BBIA0378E
SEF011V
BBIA0379E
PBIB2242E
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EC-78Revision: November 2009
BASIC SERVICE PROCEDURE
2006 QX56
Accelerator Pedal Released Position LearningUBS00KZY
DESCRIPTION
Accelerator Pedal Released Position Learning is an operation to learn the fully released position of the accel-
erator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed each time
harness connector of accelerator pedal position sensor or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON and wait at least 2 seconds.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and wait at least 2 seconds.
5. Turn ignition switch OFF and wait at least 10 seconds.
Throttle Valve Closed Position LearningUBS00KZZ
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to learn the fully closed position of the throttle valve by
monitoring the throttle position sensor output signal. It must be performed each time harness connector of
electric throttle control actuator or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON.
3. Turn ignition switch OFF wait at least 10 seconds.Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume LearningUBS00L00
DESCRIPTION
Idle Air Volume Learning is an operation to learn the idle air volume that keeps each engine within the specific
range. It must be performed under any of the following conditions:
Each time electric throttle control actuator or ECM is replaced.
Idle speed or ignition timing is out of specification.
PREPARATION
Before performing Idle Air Volume Learning, make sure that all of the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are missed for even a moment.
Battery voltage: More than 12.9V (At idle)
Engine coolant temperature: 70 - 100 °C (158 - 212 °F)
Park/Neutral position (PNP) switch: ON
Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine
is start the headlamp will not be illuminated.
Steering wheel: Neutral (Straight-ahead position)
Vehicle speed: Stopped
Transmission: Warmed-up
–With CONSULT-II: Drive vehicle until “ATF TEMP SE 1 ” in “DATA MONITOR” mode of “A/T” system indi-
cates less than 0.9V.
–Without CONSULT-II: Drive vehicle for 10 minutes.
OPERATION PROCEDURE
With CONSULT-II
1. Perform EC-78, "Accelerator Pedal Released Position Learning" .
2. Perform EC-78, "
Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.