2008 INFINITI QX56 display

DLN-112
< SYMPTOM DIAGNOSIS >[ATX14B]
HEAVY TIGHT-CORNER BRAKING SYMPTOM OCCURS
HEAVY TIGHT-CORNER BR
AKING SYMPTOM OCCURS
DescriptionINFOID:0000000001737197
This symptom occurs when the vehicle is accelerati ng in 4WD and the steering wheel is turned fully either
direction. It may feel like a bump or being pushed fr om behind. A small amount of this bumping feeling is
acceptable under certain road conditions. The transfer case may be adjusted using the CONSULT-III to com-
pensate for this condition.
Diagnosis ProcedureINFOID:0000000001737198
DIAGNOSTIC PROCEDURE
NOTE:
• Light tight-corner braking symptom may occur depending on driving conditions in AUTO mode. This is not a malfunction.
• Heavy tight-corner braking symptom occurs when vehicle is driven in the following conditions: 4WD shift
switch is 4H or 4LO, steering wheel is turned fully to either side.
1.CHECK SYSTEM FOR CAN COMMUNICATION LINE
Perform self-diagnosis. Refer to DLN-18, "
CONSULT-III Function (ALL MODE AWD/4WD)".
Is CAN COMM CIRCUIT [U1000] displayed?
YES >> Perform trouble diagnosis for CAN communication line.
NO >> GO TO 2.
2.CHECK SYSTEM FOR 4WD SHIFT SWITCH
Perform trouble diagnosis for 4WD shift switch system. Refer to DLN-31, "
Diagnosis Procedure".
Are the inspection results normal?
YES >> GO TO 3.
NO >> Repair or replace damaged parts.
3.CHECK ACCELERATOR PEDAL POSITION SIGNAL CIRCUIT
Perform self diagnosis for ECM. Refer to EC-63, "
CONSULT-III Function (ENGINE)".
Is any malfunction deteced by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 4.
4.CHECK SYSTEM FOR CLUT CH PRESSURE SOLENOID
Perform trouble diagnosis for clutch pressure solenoid system. Refer to DLN-70, "
Diagnosis Procedure".
Are the inspection results normal?
YES >> GO TO 5.
NO >> Repair or replace damaged parts.
5.SYMPTOM CHECK
Check again.
Are the inspection results normal?
YES >> Inspection End.
NO >> GO TO 6.
6.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to DLN-80, "
Reference Value".
Are the inspection results normal?
YES >> GO TO 7.
NO >> Check transfer control unit pin terminals fo r damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.
7.CHECK TRANSFER INNER PARTS
1. Disassemble transfer assembly. Refer to DLN-140, "
Disassembly and Assembly".
2. Check transfer inner parts.
Revision: March 2010 2008 QX56

DLN-114
< SYMPTOM DIAGNOSIS >[ATX14B]
ATP SWITCH
ATP SWITCH
DescriptionINFOID:0000000001737199
The ATP indicator is ON when the transfer case is not in neutral.
Diagnosis ProcedureINFOID:0000000001737200
DIAGNOSTIC PROCEDURE
1.CHECK ATP SWITCH SIGNAL

With CONSULT-III
1. Start engine.
2. Select DATA MONITOR mode for ALL MODE AWD/4WD with CONSULT-III.
3. Read out the value of ATP SWITCH.
Without CONSULT-III
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
Are inspection results normal?
YES >> GO TO 5.
NO >> GO TO 2.
2.CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND ATP SWITCH
1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the ATP switch harness connector.
3. Check continuity between transfer control unit harness connec- tor E143 terminal 40 and ATP switch harness connector F55 ter-
minal 8.
Also check harness for short to ground and short to power.
Are inspection results normal?
YES >> GO TO 3.
NO >> Repair or replace damaged parts.
3.CHECK GROUND CIRCUIT
Condition Display value
• Vehicle stopped
• Engine running
• A/T selector lever N
• Brake pedal de- pressed 4WD shift switch
: 4H to 4LO or 4LO to 4H
(While actuator motor is operating.)
ON
Except the above OFF
Connector TerminalConditionVoltage
(Approx.)
E143 40 -
Ground • Vehicle stopped
• Engine running
• A/T selector lever
N
• Brake pedal de- pressed 4WD shift switch: 4H
to 4LO or 4LO to 4H
(While actuator motor
is operating.)
0V
Except the above Battery
voltage
SDIA2755E
Continuity should exist.
SDIA2756E
Revision: March 2010
2008 QX56

EC-10
< BASIC INSPECTION >[VK56DE]
DIAGNOSIS AND REPAIR WORKFLOW
2.CHECK DTC*1
1. Check DTC*1 .
2. Perform the following procedure if DTC*
1 is displayed.
- Record DTC*
1 and freeze frame data*2 . (Print them out with CONSULT-III or GST.)
- Erase DTC*
1 . (Refer to EC-462, "DTC Index" .)
- Study the relationship between the cause detected by DTC*
1 and the symptom described by the cus-
tomer. (Symptom Matrix Chart is useful. Refer to EC-481, "
Symptom Matrix Chart" .)
3. Check related service bulletins for information.
Is any symptom described and any DTC detected?
Symptom is described, DTC*1 is displayed>>GO TO 3.
Symptom is described, DTC*
1 is not displayed>>GO TO 4.
Symptom is not described, DTC*
1 is displayed>>GO TO 5.
3.CONFIRM THE SYMPTOM
Try to confirm the symptom described by the customer (except MIL ON).
DIAGNOSIS WORK SHEET is useful to verify the incident.
Connect CONSULT-III to the vehicle and check real time diagnosis results.
Verify relation between the symptom and the condition when the symptom is detected.
>> GO TO 5.
4.CONFIRM THE SYMPTOM
Try to confirm the symptom described by the customer.
DIAGNOSIS WORK SHEET is useful to verify the incident.
Connect CONSULT-III to the vehicle and check real time diagnosis results.
Verify relation between the symptom and the condition when the symptom is detected.
>> GO TO 6.
5.PERFORM DTC CONFIRMATION PROCEDURE
Perform DTC Confirmation Procedure for the displayed DTC* , and then make sure that DTC*
1 is detected
again.
If two or more DTCs*
1 are detected, refer to EC-461, "DTC Inspection Priority Chart" and determine trouble
diagnosis order.
NOTE:
• Freeze frame data*
2 is useful if the DTC*1 is not detected.
• Perform Overall Function Check if DTC Confirma tion Procedure is not included on Service Manual. This
simplified check procedure is an effective alternative though DTC*
1 cannot be detected during this check.
If the result of Overall Function Check is NG, it is the same as the detection of DTC*
1 by DTC Confirmation
Procedure.
Is DTC*
1 detected?
Yes >> GO TO 10.
No >> Check according to GI-38, "
Intermittent Incident" .
6.PERFORM BASIC INSPECTION
Perform EC-13, "
Basic Inspection" .
With CONSULT-III>>GO TO 7.
Without CONSULT-III>>GO TO 9.
7.PERFORM SPEC IN DATA MONITOR MODE
With CONSULT-III
Make sure that “MAS A/F SE-B1”, “B/FUEL SCHDL”, and “A/F ALPHA-B1”, “A/F ALPHA-B2” are within the SP
value using CONSULT-III “SPEC” in “DATA MONITOR” mode. Refer to EC-75
.
Revision: March 2010 2008 QX56

DIAGNOSIS AND REPAIR WORKFLOWEC-11
< BASIC INSPECTION > [VK56DE]
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Are they within the SP value?
Yes >> GO TO 9.
No >> GO TO 8.
8.DETECT MALFUNCTIONING PART BY TROUBLE DIAGNOSIS - SPECIFICATION VALUE
Detect malfunctioning part according to EC-76, "
Diagnosis Procedure".
Is malfunctioning part detected?
Yes >> GO TO 11.
No >> GO TO 9.
9.DETECT MALFUNCTIONING SYST EM BY SYMPTOM MATRIX CHART
Detect malfunctioning system according to EC-481, "
Symptom Matrix Chart" based on the confirmed symp-
tom in step 4, and determine the trouble diagnosis order based on possible causes and symptom.
>> GO TO 10.
10.DETECT MALFUNCTIONING PART BY DIAGNOSTIC PROCEDURE
Inspect according to Diagnostic Procedure of the system.
NOTE:
The Diagnostic Procedure in EC section described based on open circuit inspection. A short circuit inspection
is also required for the circuit check in the Diagnostic Procedure. For details, refer to Circuit Inspection in GI-
34, "Work Flow".
Is malfunctioning part detected?
Yes >> GO TO 11.
No >> Monitor input data from related sensors or check voltage of related ECM terminals using CON- SULT-III. Refer to EC-429, "
ECM Terminal and Reference Value", EC-426, "CONSULT-lll Refer-
ence Value in Data Monitor Mode".
11 .REPAIR OR REPLACE THE MALFUNCTIONING PART
1. Repair or replace the malfunctioning part.
2. Reconnect parts or connectors disconnected during Diagnostic Procedure again after repair and replace-
ment.
3. Check DTC. If DTC is displayed, erase it, refer to EC-462, "
DTC Index".
>> GO TO 12.
12.FINAL CHECK
When DTC was detected in step 2, perform DTC Confirmation Procedure or Overall Function Check again,
and then make sure that the malfunction have been repaired securely.
When symptom was described from the customer, refer to confirmed symptom in step 3 or 4, and make sure
that the symptom is not detected.
OK or NG
NG (DTC*1 is detected)>>GO TO 10.
NG (Symptom remains)>>GO TO 6.
OK >> 1. Before returning the vehicle to the cu stomer, make sure to erase unnecessary DTC*
1 in ECM
and TCM (Transmission Control Module). (Refer to EC-462, "
DTC Index" and TM-30, "OBD-
II Diagnostic Trouble Code (DTC)".)
2. If the completion of SRT is needed, drive vehicle under the specific driving pattern. Refer to EC-462, "
DTC Index".
3. INSPECTION END
*1: Include 1st trip DTC.
*2: Include 1st trip freeze frame data.
DIAGNOSTIC WORKSHEET
Description
Revision: March 2010 2008 QX56

INSPECTION AND ADJUSTMENTEC-13
< BASIC INSPECTION > [VK56DE]
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INSPECTION AND ADJUSTMENT
Basic InspectionINFOID:0000000001351329
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-III 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.
3.CHECK TARGET IDLE SPEED
With CONSULT-III
1. Run engine at about 2,000 rpm for about 2 minutes under no load.
SEF983U
SEF976U
SEF977U
Revision: March 2010 2008 QX56

EC-18
< BASIC INSPECTION >[VK56DE]
INSPECTION AND ADJUSTMENT
With CONSULT-III
1. Check the VIN of the vehicle and note it. Refer to
GI-20, "Model Variation".
2. Turn ignition switch ON and engine stopped.
3. Select “VIN REGISTRATION ” in “WORK SUPPORT” mode.
4. Follow the instruction of CONSULT-III display.
Accelerator Pedal Released Position LearningINFOID:0000000001351333
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 positi on sensor output signal. It must be performed each time
harness connector of accelerator pedal pos ition 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 LearningINFOID:0000000001351334
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to l earn 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 LearningINFOID:0000000001351335
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 follo wing conditions are missed for even a moment.
• Battery voltage: More than 12.9V (At idle)
• Engine coolant temperature: 70 - 100 °C (158 - 212° F)
• Selector lever: P or N
• 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-III: Drive vehicle until “ATF TEMP SE 1” in “DATA MONITOR” mode of “A/T” system indi- cates less than 0.9V.
- Without CONSULT-III: Drive vehicle for 10 minutes.
OPERATION PROCEDURE
Revision: March 2010 2008 QX56

INSPECTION AND ADJUSTMENTEC-19
< BASIC INSPECTION > [VK56DE]
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With CONSULT-III
1. Perform
EC-18, "Accelerator Pedal Released Position Learning" .
2. Perform EC-18, "
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 PREP ARATION (previously mentioned) are in good order.
5. Select “IDLE AIR VOL LEA RN” in “WORK SUPPORT” mode.
6. Touch “START” and wait 20 seconds.
7. Make sure that “CMPLT” is displayed on CONSULT-III screen. If “CMPLT” is not displayed, Idle Air Vol-
ume Learning will not be carried out successfully. In this case, find the cause of the incident by referring to
the DIAGNOSTIC PROCEDURE below.
8. Rev up the engine two or three times and make sure that idle speed and ignition timing are within the specifications.
Without CONSULT-III
NOTE:
•It is better to count the time accurately with a clock.
• It is impossible to switch the di agnostic mode when an accelerator pedal position sensor circuit has
a malfunction.
1. Perform EC-18, "
Accelerator Pedal Released Position Learning" .
2. Perform EC-18, "
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 PREP ARATION (previously mentioned) are in good order.
5. Turn ignition switch OFF and wait at least 10 seconds.
6. Confirm that accelerator pedal is fully releas ed, turn ignition switch ON and wait 3 seconds.
7. Repeat the following procedure quick ly five times within 5 seconds.
a. Fully depress the accelerator pedal.
b. Fully release the accelerator pedal.
8. Wait 7 seconds, fully depress the accelerator pedal and keep it for approx. 20 seconds until the MIL stops blinking and turned ON.
9. Fully release the accelerator pedal within 3 seconds after the MIL turned ON.
10. Start engine and let it idle.
11. Wait 20 seconds.
12. Rev up the engine two or three times and make sure that idle speed and ignition timing are within the specifications.
ITEM SPECIFICATION
Idle speed 650 ± 50 rpm (in P or N position)
Ignition timing 15 ± 5° BTDC (in P or N position)
SEC897C
Revision: March 2010 2008 QX56

ON BOARD DIAGNOSTIC (OBD) SYSTEMEC-41
< FUNCTION DIAGNOSIS > [VK56DE]
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ON BOARD DIAGNOSTIC (OBD) SYSTEM
IntroductionINFOID:0000000001351323
The ECM has an on board diagnostic system, which detects malfunctions related to engine sensors or actua-
tors. The ECM also records various emission-related diagnostic information including:
The above information can be checked using procedures listed in the table below.
×
: Applicable —: Not applicable
*: When DTC and 1st trip DTC simultaneously appear on the display, they cannot be clearly distinguished from each other.
The malfunction indicator lamp (MIL) on the instrument panel lights up when the same malfunction is detected
in two consecutive trips (Two trip detection logic) , or when the ECM enters fail-safe mode. (Refer to EC-459,
"Fail-Safe Chart".)
Two Trip Detection LogicINFOID:0000000001351324
When a malfunction is detected for the first time, 1st tr ip DTC and 1st trip Freeze Frame data are stored in the
ECM memory. The MIL will not light up at this stage. <1st trip>
If the same malfunction is detected again during the next drive, the DTC and Freeze Frame data are stored in
the ECM memory, and the MIL lights up. The MIL lights up at the same time when the DTC is stored. <2nd
trip> The “trip” in the “Two Trip Detection Logic” m eans a driving mode in which self-diagnosis is performed
during vehicle operation. Specific on board diagnostic item s will cause the ECM to light up or blink the MIL,
and store DTC and Freeze Frame data, even in the 1st trip, as shown below.
× : Applicable —: Not applicable
When there is an open circuit on MIL circuit, the ECM c annot warn the driver by lighting up MIL when there is
malfunction on engine control system.
Emission-related diagnostic information Diagnostic service
Diagnostic Trouble Code (DTC) Service $03 of SAE J1979
Freeze Frame data Service $02 of SAE J1979
System Readiness Test (SRT) code Service $01 of SAE J1979
1st Trip Diagnostic Trou ble Code (1st Trip DTC) Service $07 of SAE J1979
1st Trip Freeze Frame data
Test values and Test limits Service $06 of SAE J1979
Calibration ID Service $09 of SAE J1979
DTC 1st trip DTC Freeze
Frame data 1st trip Freeze
Frame data SRT code SRT status Test value
CONSULT-III ×× × × × × —
GST ×× × —×××
ECM ××*— — — ×—
Items MIL
DTC1st trip DTC
1st trip 2nd trip
1st trip
displaying 2nd trip
displaying 1st trip
displaying 2nd trip
display- ing
Blinking Lighting
up Blinking Lighting
up
Misfire (Possible three way catalyst
damage) — DTC: P0300 - P0308 is
being detected ×
———— — ×—
Misfire (Possible three way catalyst
damage) — DTC: P0300 - P0308 is
being detected ——
×—— ×——
One trip detection diagnoses (Re-
fer to EC-462, "
DTC Index".) —
×—— ×———
Except above — — —×— ×× —
Revision: March 2010 2008 QX56