2007 INFINITI QX56 Cruise

TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
ACS-29
< SERVICE INFORMATION >[ICC]
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1. Touch “ACTIVE TEST” on "SELECT DIAG MODE" screen.
2. Touch any of “ICC BUZZER 1”, “METER LAMP”, “STOP LAMP”
and “BOOSTER SOL/V 3” on "SELECT TEST ITEM" screen.
3. Touch “START”.
4. Active test screen will be shown.
ICC BUZZER 1
• Touch “ON” and “OFF” to check that ICC warning chime operates
as in the following chart.
METER LAMP
• Start engine.
• Touch “ON” and “OFF” to check that ICC system displays operate as required.
• The following ICC lamps will illuminate at the same time, CRUISE
(orange), CRUISE (green), SET and ICC digital display.
STOP LAMP
BCIA0031E
SKIA6195E
ICC BUZZER 1 ON OFF
Buzzer sound Beep Not activated
SKIA1228E
METER LAMP ON OFF
All ICC system displays Full illumination OFF
SKIA1231E

ACS-34
< SERVICE INFORMATION >[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Diagnostic Trouble Code (DTC) ChartINFOID:0000000003533794
×:Applicable
DTC
No.CONSULT-II screen termsICC sys-
tem
warning
lampFail-safe
Malfunctions detected where...Refer-
ence
page Vehicle-
to-vehi-
cle dis-
tance
control
modeConven-
tional
(fixed
speed)
cruise
control
modeBrake as-
sist (with
preview
function)
11 CONTROL UNIT×××ו ICC unit internal malfunctionACS-36,
"DTC 11
CON-
TROL
UNIT"
12 VDC CONTROL UNIT×××ו VDC malfunction
• Brake booster signal harness is
open or shortedACS-36,
"DTC 12
VDC
CON-
TROL
UNIT"
20 CAN COMM CIRCUIT×××ו ICC unit detected CAN communi-
cation malfunctionACS-37,
"DTC 20
CAN
COMM
CIR-
CUIT"
31 POWER SUPPLY CIR1×××ו ICC unit power supply voltage is
excessively low (less than 8V)ACS-37,
"DTC 31
POWER
SUPPLY
CIR1,
DTC 34
POWER
SUPPLY
CIR2"
34 POWER SUPPLY CIR2×××ו ICC unit power supply voltage is
excessively high.ACS-37,
"DTC 31
POWER
SUPPLY
CIR1,
DTC 34
POWER
SUPPLY
CIR2"
41 VHCL SPEED SE CIRC×××ו Wheel sensor malfunction
• ABS actuator and electric unit
(control unit) malfunction
• A/T vehicle speed sensor mal-
function
•TCM malfunctionACS-38,
"DTC 41
VHCL
SPEED
SE CIRC"
43 VDC/TCS/ABS CIRC×××ו VDC/TCS/ABS system malfunc-
tionACS-38,
"DTC 43
VDC/
TCS/ABS
CIRC"

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
ACS-35
< SERVICE INFORMATION >[ICC]
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45 BRAKE SW/ STOP L SW×××ו ICC brake switch or stop lamp
switch harness is open or shorted
• ICC brake switch or stop lamp
switch is stuck to OFF
• ICC brake switch or stop lamp
switch is stuck to ONACS-38,
"DTC 45
BRAKE
SW/
STOP L
SW"
46 OPERATION SW CIRC××ו ICC steering switch harness or
spiral cable is open or shorted
• ICC steering switch malfunctionACS-40,
"DTC 46
OPERA-
TION SW
CIRC"
74 LASER BEAM OFF CNTR×× ×• Laser beam of ICC sensor is off
the aiming pointACS-41,
"DTC 74
LASER
BEAM
OFF CN-
TR"
90 STOP LAMP RLY FIX×× ×• Normally open terminal of stop
lamp relay is stuckACS-41,
"DTC 90
STOP
LAMP
RLY FIX"
92 ECM CIRCUIT×××וECM malfunction
• Accelerator pedal position sensor
malfunction
• ICC unit malfunctionACS-45,
"DTC 92
ECM
CIR-
CUIT"
96 NP RANGE××ו Park/neutral position switch har-
ness is open or shorted
• Park/neutral position switch mal-
function
•TCM malfunctionACS-45, "DTC 96
NP
RANGE"
97 AT CIRCUIT××וTCM malfunctionACS-46, "DTC 97
AT CIR-
CUIT"
98 GEAR POSITION××וTCM malfunction
• A/T turbine revolution sensor mal-
function
• A/T vehicle speed sensor mal-
functionACS-46,
"DTC 98
GEAR
POSI-
TION"
102 LASER STAIN×× ×• ICC sensor body window has
contaminationACS-47, "DTC 102
LASER
STAIN"
103 LASER SENSOR FAIL×× ×• ICC sensor internal malfunctionACS-47,
"DTC 103
LASER
SEN-
SOR
FA I L"
DTC
No.CONSULT-II screen termsICC sys-
tem
warning
lampFail-safe
Malfunctions detected where...Refer-
ence
page Veh ic le-
to-vehi-
cle dis-
tance
control
modeConven-
tional
(fixed
speed)
cruise
control
modeBrake as-
sist (with
preview
function)

ACS-36
< SERVICE INFORMATION >[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
NOTE: DTC 55 will display when no malfunction is detected.
DTC 11 CONTROL UNITINFOID:0000000003533795
1.DIAGNOSTIC CHECK
Are any items other than “DTC 11 CONTROL UNIT” indicated on self-diagnosis display?
YES or NO
YES >> Repair or replace as necessary. Erase DTC and perform ICC system running test. Refer to ACS-
9, "ICC System Running Test" . Then perform self-diagnosis of ICC system again.
NO >> Replace ICC unit. Refer to ACS-55
. Erase DTC and perform ICC system running test. Refer to
ACS-9, "
ICC System Running Test". Then perform self-diagnosis of ICC system again.
DTC 12 VDC CONTROL UNITINFOID:0000000003533796
1.DIAGNOSIS CHECK
With CONSULT-II
Perform self-diagnosis of ABS actuator and electric unit (control unit). Is malfunction indicated?
YES or NO
YES >> Repair or replace as necessary. Erase DTC and perform ICC system running test. Refer to ACS-
9, "ICC System Running Test". Then perform self-diagnosis of ICC system again.
NO >> GO TO 2.
2.CHECK CONNECTOR ICC UNIT AND ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
1. Turn ignition switch OFF.
2. Disconnect ICC unit, and ABS actuator and electric unit (control unit) connectors, and connect them
securely again. Erase DTC, then perform self-diagnosis of ICC system again.
OK or NG
OK >> Poor connector connection. Check connector housing for disconnected, loose, bent and collapsed
terminals. If any malfunction is detected, repair as necessary. Erase DTC and perform ICC sys-
tem running test. Refer to ACS-9, "
ICC System Running Test". Then perform self-diagnosis of ICC
system again.
NG >> GO TO 3.
3.CHECK HARNESS BETWEEN ICC UNIT AND ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
104 LASER AIMING INCMP×× ×• Laser beam aiming of ICC sensor
is not adjustedACS-48,
"DTC 104
LASER
AIMING
INCMP"
107 LASER COMM FAIL×× ×• CAN data received by ICC sensor
is strange (from ICC unit, combi-
nation meter or ECM)ACS-48,
"DTC 107
LASER
COMM
FA IL"
109 LASER HIGH TEMP×× ×• Temperature around ICC sensor
is excessively highACS-48,
"DTC 109
LASER
HIGH
TEMP"
DTC
No.CONSULT-II screen termsICC sys-
tem
warning
lampFail-safe
Malfunctions detected where...Refer-
ence
page Vehicle-
to-vehi-
cle dis-
tance
control
modeConven-
tional
(fixed
speed)
cruise
control
modeBrake as-
sist (with
preview
function)

TROUBLE DIAGNOSIS FOR SYMPTOMS
ACS-49
< SERVICE INFORMATION >[ICC]
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TROUBLE DIAGNOSIS FOR SYMPTOMS
Symptom ChartINFOID:0000000003533814
Symptom 1 ON/OFF Switch Does Not Switch ON*1, ON/OFF Switch Does Not Switch
OFF
*2INFOID:0000000003533815
NOTE:
• *1: The ICC system display in the combination meter does not illuminate.
• *2: The ICC system display in the combination meter remains powered.
1.CHECK ON/OFF SWITCH
With CONSULT-II
• With "DATA MONITOR" on the CONSULT-II, check that ON/OFF switch operates normally.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
Symptoms Reference page
OperationON/OFF switch does not switch ON.Symptom 1
ACS-49
ON/OFF switch does not switch OFF.Symptom 1
ACS-49
Cruise does not function for setting (powering functions).Symptom 2
ACS-50
CANCEL switch does not function.Symptom 3
ACS-51
RESUME does not function.Symptom 3
ACS-51
The set speed does not increase.Symptom 3
ACS-51
The set distance to the vehicle ahead cannot be changed.Symptom 3
ACS-51
The ICC is not cancelled when the gear is in "N".Symptom 4
ACS-51
Display/ChimeThe ICC system display does not appear.Check combination meter. Refer to
DI-15, "
How to Proceed with Trou-
ble Diagnosis"
Chime does not function.Symptom 5
ACS-51
Control Driving force is hunting.Symptom 6
ACS-52
Function to detect the vehicle
aheadThe system frequently cannot detect the vehicle ahead.Symptom 7
ACS-52
The distance to detect the vehicle ahead is short.Symptom 7
ACS-52
The system misidentifies a vehicle even though there is no ve-
hicle ahead.• Refer toACS-12
• Refer to ACS-9, "
ICC System
Running Test"
The system misidentifies a vehicle in the next lane.• Refer to ACS-12• Refer to ACS-9, "ICC System
Running Test"
The system does not detect a vehicle at all.Symptom 8
ACS-53

AT-1
TRANSMISSION/TRANSAXLE
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SECTION AT
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CONTENTS
AUTOMATIC TRANSMISSION
SERVICE INFORMATION ............................6
INDEX FOR DTC .................................................6
Alphabetical Index .....................................................6
DTC No. Index ..........................................................6
PRECAUTIONS ...................................................8
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ...................................................................
8
Precaution for On Board Diagnosis (OBD) System
of A/T and Engine .....................................................
8
Precaution .................................................................8
Service Notice or Precaution .....................................9
PREPARATION ..................................................11
Special Service Tool ...............................................11
Commercial Service Tool ........................................12
A/T FLUID ...........................................................13
Changing Automatic Transmission Fluid (ATF) ......13
Checking Automatic Transmission Fluid (ATF) .......13
A/T Fluid Cooler Cleaning .......................................15
A/T CONTROL SYSTEM ....................................19
Cross-Sectional View (2WD models) ......................19
Cross-Sectional View (4WD models) ......................20
Shift Mechanism ......................................................20
TCM Function ..........................................................31
CAN Communication ...............................................32
Input/Output Signal of TCM .....................................33
Line Pressure Control .............................................33
Shift Control ............................................................35
Lock-up Control .......................................................36
Engine Brake Control ..............................................37
Control Valve ...........................................................37
ON BOARD DIAGNOSTIC (OBD) SYSTEM ......39
Introduction .............................................................39
OBD-II Function for A/T System ..............................39
One or Two Trip Detection Logic of OBD-II ............39
OBD-II Diagnostic Trouble Code (DTC) ..................39
Malfunction Indicator Lamp (MIL) ............................41
TROUBLE DIAGNOSIS ....................................43
DTC Inspection Priority Chart ..................................43
Fail-Safe ..................................................................43
How To Perform Trouble Diagnosis for Quick and
Accurate Repair .......................................................
44
A/T Electrical Parts Location ...................................50
Circuit Diagram ........................................................51
Inspections Before Trouble Diagnosis .....................51
Check Before Engine Is Started ..............................55
Check at Idle ............................................................55
Cruise Test - Part 1 .................................................56
Cruise Test - Part 2 .................................................58
Cruise Test - Part 3 .................................................59
Vehicle Speed When Shifting Gears .......................59
Vehicle Speed When Performing and Releasing
Complete Lock-up ...................................................
60
Vehicle Speed When Performing and Releasing
Slip Lock-up .............................................................
60
Symptom Chart ........................................................60
TCM Input/Output Signal Reference Value .............82
CONSULT-II Function (A/T) ....................................83
DTC U1000 CAN COMMUNICATION LINE .....91
Description ...............................................................91
On Board Diagnosis Logic .......................................91
Possible Cause ........................................................91
DTC Confirmation Procedure ..................................91
Wiring Diagram - AT - CAN .....................................92
Diagnosis Procedure ...............................................93
DTC P0615 START SIGNAL CIRCUIT .............94
Description ...............................................................94
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................
94
On Board Diagnosis Logic .......................................94
Possible Cause ........................................................94
DTC Confirmation Procedure ..................................94
Wiring Diagram - AT - STSIG ..................................95
Diagnosis Procedure ...............................................95

TROUBLE DIAGNOSIS
AT-55
< SERVICE INFORMATION >
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ROAD TEST
Description
• The road test inspects overall performance of the A/T and analyzes possible malfunction causes.
• The road test is carried out in the following three stages.
1. Check before engine is started. Refer to AT- 5 5
.
2. Check at idle. Refer to AT- 5 5
3. Cruise test
• Inspect all the items from Part 1 to Part 3. Refer to AT- 5 6
, AT- 5 8, AT- 5 9.
• Before beginning the road test, check the test procedure and inspection items.
• Test all inspection items until the symptom is uncovered. Diagnose NG items when all road tests are com-
plete.
Check Before Engine Is StartedINFOID:0000000003532249
1.CHECK AT CHECK INDICATOR LAMP
1. Park vehicle on level surface.
2. Move selector lever to “P” position.
3. Turn ignition switch to “OFF” position and wait at least 10 seconds.
4. Turn ignition switch to “ON” position. (Do not start engine.)
Does AT CHECK indicator lamp light up for about 2 seconds?
YES >> 1. Turn ignition switch to “OFF” position.
2. Carry out the self-diagnostics and record all NG items on the diagnostics worksheet. Refer to
AT-83, "
CONSULT-II Function (A/T)".
3. Go to AT-55, "
Check at Idle".
NO >> Stop the road test and go to AT-167, "
A/T Check Indicator Lamp Does Not Come On".
Check at IdleINFOID:0000000003532250
1.CHECK STARTING THE ENGINE
1. Park vehicle on level surface.
2. Move selector lever to “P” or “N” position.
3. Turn ignition switch to “OFF” position.
4. Turn ignition switch to “START” position.
Does the engine start?
YES >> GO TO 2.
NO >> Stop the road test and go to AT-168, "
Engine Cannot Be Started in "P" or "N" Position".
2.CHECK STARTING THE ENGINE
1. Turn ignition switch to “ON” position.
2. Move selector lever in “D”,“4”, “3”, “2”, “1” or “R” position.
Stall speedOil pressure does
not rise higher than
the oil pressure for
idle.Possible causes include a sensor malfunction or malfunction in the pressure adjustment function.
For example
• Accelerator pedal position signal malfunction
• TCM breakdown
• Line pressure solenoid malfunction (shorting, sticking in“ ON” state)
• Pressure regulator valve or plug sticking
• Pilot valve sticking or pilot filter clogged
The pressure rises,
but does not enter
the standard posi-
tion.Possible causes include malfunctions in the pressure supply system and malfunction in the pres-
sure adjustment function.
For example
• Accelerator pedal position signal malfunction
• Line pressure solenoid malfunction (sticking, filter clog)
• Pressure regulator valve or plug sticking
• Pilot valve sticking or pilot filter clogged
Only low for a spe-
cific positionPossible causes include an oil pressure leak in a passage or device related to the position after
the pressure is distributed by the manual valve. Judgement Possible cause

AT-56
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
3. Turn ignition switch to “START” position.
Does the engine start in either position?
YES >> Stop the road test and go to AT-168, "Engine Cannot Be Started in "P" or "N" Position".
NO >> GO TO 3.
3.CHECK “P” POSITION FUNCTIONS
1. Move selector lever to “P” position.
2. Turn ignition switch to “OFF” position.
3. Release the parking brake.
4. Push the vehicle forward or backward.
5. Engage the parking brake.
When you push the vehicle with disengaging the parking brake, does it move?
YES >> Enter a check mark at “In “P” Position Vehicle Moves When Pushed” on the diagnostics work-
sheet, then continue the road test.
NO >> GO TO 4.
4.CHECK “N” POSITION FUNCTIONS
1. Start the engine.
2. Move selector lever to “N” position.
3. Release the parking brake.
Does vehicle move forward or backward?
YES >> Enter a check mark at “In “N” Position Vehicle Moves” on the diagnostics worksheet, then con-
tinue the road test.
NO >> GO TO 5.
5.CHECK SHIFT SHOCK
1. Engage the brake.
2. Move selector lever to “D” position.
When the transmission is shifted from
“N” to “D”, is there an excessive shock?
YES >> Enter a check mark at “Large Shock ("N" to "D" Position) on the diagnostics worksheet, then con-
tinue the road test.
NO >> GO TO 6.
6.CHECK “R” POSITION FUNCTIONS
1. Engage the brake.
2. Move selector lever to “R” position.
3. Release the brake for 4 to 5 seconds.
Does the vehicle creep backward?
YES >> GO TO 7.
NO >> Enter a check mark at “Vehicle Does Not Creep Backward In "R" Position” on the diagnostics
worksheet, then continue the road test.
7.CHECK “D” POSITION FUNCTIONS
Inspect whether the vehicle creeps forward when the transmission is put into the “D” position.
Does the vehicle creep forward in the
“D” positions?
YES >> Go to AT-56, "Cruise Test - Part 1", AT-58, "Cruise Test - Part 2", and AT-59, "Cruise Test - Part 3".
NO >> Enter a check mark at “Vehicle Does Not Creep Forward in "D" Position” on the diagnostics work-
sheet, then continue the road test.
Cruise Test - Part 1INFOID:0000000003532251
1.CHECK STARTING OUT FROM D1
1. Drive the vehicle for about 10 minutes to warm up the engine oil and ATF.
Appropriate temperature for the ATF: 50 - 80°C (122 - 176°F)
2. Park the vehicle on a level surface.
3. Move selector lever to “P” position.
4. Start the engine.
5. Move selector lever to “D” position.