cruise control INFINITI QX56 2007 Factory User Guide

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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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

AT-88
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
POWERSHIFT SW (ON-OFF display) X — X
Not mounted but displayed. HOLD SW (ON-OFF display) X — X
MANU MODE SW (ON-OFF display) X — X
NON M-MODE SW (ON-OFF display) X — X
UP SW LEVER (ON-OFF display) X — X
DOWN SW LEVER (ON-OFF display) X — X
SFT UP ST SW (ON-OFF display) — — X
SFT DWN ST SW (ON-OFF display) — — X
ASCD-OD CUT (ON-OFF display) — — X
ASCD-CRUISE (ON-OFF display) — — X
ABS SIGNAL (ON-OFF display) — — X
ACC OD CUT (ON-OFF display) — — X
ICC (Intelligent cruise control)
ACC SIGNAL (ON-OFF display) — — X
TCS GR/P KEEP (ON-OFF display) — — X
TCS SIGNAL 2 (ON-OFF display) — — X
TCS SIGNAL 1 (ON-OFF display) — — X
TCC SOLENOID (A) — X X
LINE PRES SOL (A) — X X
I/C SOLENOID (A) — X X
FR/B SOLENOID (A) — X X
D/C SOLENOID (A) — X X
HLR/C SOL (A) — X X
ON OFF SOL (ON-OFF display) — — X LC/B solenoid
TCC SOL MON (A) — — X
L/P SOL MON (A) — — X
I/C SOL MON (A) — — X
FR/B SOL MON (A) — — X
D/C SOL MON (A) — — X
HLR/C SOL MON (A) — — X
ONOFF SOL MON (ON-OFF display) — — X LC/B solenoid
P POSI IND (ON-OFF display) — — X
R POSI IND (ON-OFF display) — — X
N POSI IND (ON-OFF display) — — X
D POSI IND (ON-OFF display) — — X
4TH POSI IND (ON-OFF display) — — X
3RD POSI IND (ON-OFF display) — — X
2ND POSI IND (ON-OFF display) — — X
1ST POSI IND (ON-OFF display) — — X
MANU MODE IND (ON-OFF display) — — X
Not mounted but displayed.
POWER M LAMP (ON-OFF display) — — X
F-SAFE IND/L (ON-OFF display) — — XMonitored item (Unit)Monitor Item Selection
Remarks ECU IN-
PUT SIG-
NALSMAIN SIG-
NALSSELEC-
TION
FROM
MENU

AT-194
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS FOR SYMPTOMS
5.CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-210, "
Control Valve with TCM and A/T Fluid Temperature Sensor 2".
2. Check A/T fluid condition. Refer to AT-51, "
Inspections Before
Trouble Diagnosis".
OK or NG
OK >> GO TO 6.
NG >> GO TO 9.
6.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.14).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7.CHECK SYMPTOM
Check again. Refer to AT-59, "
Cruise Test - Part 3".
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
8.PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-82, "
TCM Input/Output Signal Reference
Va l u e".
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
9.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.14).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
A/T Does Not Shift: 4th gear → 3rd gearINFOID:0000000003532465
SYMPTOM:
When shifted from 44 to 33 position, does not downshift from 4th to 3rd gears.
DIAGNOSTIC PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Perform self-diagnosis. Refer to AT-83, "
CONSULT-II Function (A/T)".
Do the self-diagnosis results indicate PNP switch, ATF pressure switch 1, ATF pressure switch 3?
YES >> Check the malfunctioning system. Refer to AT- 9 9, AT-150' AT-152.
NO >> GO TO 2.
2.CHECK A/T FLUID LEVEL
SCIA5199E

TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-195
< SERVICE INFORMATION >
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Check the A/T fluid level. Refer to AT-13, "Checking Automatic
Transmission Fluid (ATF)".
OK or NG
OK >> GO TO 3.
NG >> Refill ATF.
3.CHECK CONTROL CABLE
Check the control cable.
• Refer to AT-208, "
Checking of A/T Position".
OK or NG
OK >> GO TO 4.
NG >> Adjust control cable. Refer to AT-208, "
Adjustment of A/
T Position".
4.CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-210, "
Control Valve with TCM and A/T Fluid Temperature Sensor 2".
2. Check A/T fluid condition. Refer to AT-51, "
Inspections Before
Trouble Diagnosis".
OK or NG
OK >> GO TO 5.
NG >> GO TO 8.
5.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.15).
OK or NG
OK >> GO TO 6.
NG >> Repair or replace damaged parts.
6.CHECK SYMPTOM
Check again. Refer to AT-59, "
Cruise Test - Part 3".
OK or NG
OK >>INSPECTION END
NG >> GO TO 7.
7.PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-82, "
TCM Input/Output Signal Reference
Va l u e".
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
SAT638A
LCIA0345E
SCIA5199E

TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-199
< SERVICE INFORMATION >
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1. Remove oil pan. Refer to AT-210, "Control Valve with TCM and A/T Fluid Temperature Sensor 2".
2. Check A/T fluid condition. Refer to AT-51, "
Inspections Before
Trouble Diagnosis".
OK or NG
OK >> GO TO 6.
NG >> GO TO 9.
6.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.17).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7.CHECK SYMPTOM
Check again. Refer to AT-58, "
Cruise Test - Part 2".
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
8.PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-82, "
TCM Input/Output Signal Reference
Va l u e".
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
9.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.17).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
Vehicle Does Not Decelerate By Engine BrakeINFOID:0000000003532468
SYMPTOM:
No engine brake is applied when the gear is shifted from the 22 to 11.
DIAGNOSTIC PROCEDURE
1.CHECK SELF-DIAGNOSIS RESULTS
Perform self-diagnosis.
Do the self-diagnosis results indicate PNP switch, ATF pressure switch 5?
YES >> Check the malfunctioning system. Refer to AT- 9 9' AT-154.
NO >> GO TO 2.
2.CHECK 1ST POSITION SWITCH CIRCUIT
With CONSULT-II
SCIA5199E

TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-201
< SERVICE INFORMATION >
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1. Remove oil pan. Refer to AT-210, "Control Valve with TCM and A/T Fluid Temperature Sensor 2".
2. Check A/T fluid condition. Refer to AT-51, "
Inspections Before
Trouble Diagnosis".
OK or NG
OK >> GO TO 6.
NG >> GO TO 9.
6.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.53).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
7.CHECK SYMPTOM
Check again. Refer to AT-59, "
Cruise Test - Part 3".
OK or NG
OK >>INSPECTION END
NG >> GO TO 8.
8.PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-82, "
TCM Input/Output Signal Reference
Va l u e".
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.
9.DETECT MALFUNCTIONING ITEM
• Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-60,
"Symptom Chart" (Symptom No.53).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
SCIA5199E

EC-30
< SERVICE INFORMATION >
AUTOMATIC SPEED CONTROL DEVICE (ASCD)
AUTOMATIC SPEED CONTROL DEVICE (ASCD)
System DescriptionINFOID:0000000003531591
INPUT/OUTPUT SIGNAL CHART
*: This signal is sent to the ECM through CAN communication line
BASIC ASCD SYSTEM
Refer to Owner's Manual for ASCD operating instructions.
Automatic Speed Control Device (ASCD) allows a driver to keep vehicle at predetermined constant speed
without depressing accelerator pedal. Driver can set vehicle speed in advance between approximately 40 km/
h (25 MPH) and 144 km/h (89 MPH).
ECM controls throttle angle of electric throttle control actuator to regulate engine speed.
Operation status of ASCD is indicated by CRUISE indicator and SET indicator in combination meter. If any
malfunction occurs in ASCD system, it automatically deactivates control.
NOTE:
Always drive vehicle in safe manner according to traffic conditions and obey all traffic laws.
SET OPERATION
Press MAIN switch. (The CRUISE indicator in combination meter illuminates.)
When vehicle speed reaches a desired speed between approximately 40 km/h (25 MPH) and 144 km/h (89
MPH), press SET/COAST switch. (Then SET indicator in combination meter illuminates.)
ACCELERATE OPERATION
If the RESUME/ACCELERATE switch is pressed during cruise control driving, increase the vehicle speed until
the switch is released or vehicle speed reaches maximum speed controlled by the system.
And then ASCD will keep the new set speed.
CANCEL OPERATION
When any of following conditions exist, cruise operation will be canceled.
• CANCEL switch is pressed
• More than 2 switches at ASCD steering switch are pressed at the same time (Set speed will be cleared)
• Brake pedal is depressed
• Selector lever is changed to N, P, R position
• Vehicle speed decreased to 13 km/h (8 MPH) lower than the set speed
• VDC system is operated
When the ECM detects any of the following conditions, the ECM will cancel the cruise operation and inform
the driver by blinking indicator lamp.
• Engine coolant temperature is slightly higher than the normal operating temperature, CRUISE lamp may
blink slowly.
When the engine coolant temperature decreases to the normal operating temperature, CRUISE lamp will
stop blinking and the cruise operation will be able to work by pressing SET/COAST switch or RESUME/
ACCELERATE switch.
• Malfunction for some self-diagnoses regarding ASCD control: SET lamp will blink quickly.
If MAIN switch is turned to OFF during ASCD is activated, all of ASCD operations will be canceled and vehicle
speed memory will be erased.
COAST OPERATION
When the SET/COAST switch is pressed during cruise control driving, decrease vehicle set speed until the
switch is released. And then ASCD will keep the new set speed.
RESUME OPERATION
Sensor Input signal to ECM ECM function Actuator
ASCD brake switch Brake pedal operation
ASCD vehicle speed controlElectric throttle control
actuator Stop lamp switch Brake pedal operation
ASCD steering switch ASCD steering switch operation
Park/neutral position (PNP) switch Gear position
Wheel sensor Vehicle speed*
TCM Powertrain revolution*

EC-118
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
A/F S1 HTR (B1)
[%]• A/F sensor 1 heater control value com-
puted by ECM according to the input sig-
nals.
• The current flow to the heater becomes
larger as the value increases. A/F S1 HTR (B2)
[%]
AC PRESS SEN [V]• The signal voltage from the refrigerant
pressure sensor is displayed.
VHCL SPEED SE
[km/h] or [mph]• The vehicle speed computed from the
vehicle speed signal sent from combina-
tion meter is displayed.
SET VHCL SPD
[km/h] or [mph]• The preset vehicle speed is displayed.
MAIN SW
[ON/OFF]• Indicates [ON/OFF] condition from MAIN
switch signal.
CANCEL SW
[ON/OFF]• Indicates [ON/OFF] condition from CAN-
CEL switch signal.
RESUME/ACC SW
[ON/OFF]• Indicates [ON/OFF] condition from RE-
SUME/ACCELERATE switch signal.
SET SW
[ON/OFF]• Indicates [ON/OFF] condition from SET/
COAST switch signal.
BRAKE SW1
[ON/OFF]• Indicates [ON/OFF] condition from
ASCD brake switch signal.
BRAKE SW2
[ON/OFF]• Indicates [ON/OFF] condition of stop
lamp switch signal.
DIST SW
[ON/OFF]• Indicates [ON/OFF] condition from DIS-
TANCE switch signal.
VHCL SPD CUT
[NON/CUT]• Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the
ASCD set speed.
CUT: Vehicle speed increased to exces-
sively high compared with the ASCD set
speed, and ASCD operation is cut off.
LO SPEED CUT
[NON/CUT]• Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the
ASCD set speed.
CUT: Vehicle speed decreased to exces-
sively low compared with the ASCD set
speed, and ASCD operation is cut off.
AT O D M O N I T O R
[ON/OFF]• Indicates [ON/OFF] condition of A/T O/D
according to the input signal from the
TCM.
AT O D C A N C E L
[ON/OFF]• Indicates [ON/OFF] condition of A/T O/D
cancel signal sent from the TCM.
CRUISE LAMP
[ON/OFF]• Indicates [ON/OFF] condition of CRUISE
lamp determined by the ECM according
to the input signals.
SET LAMP
[ON/OFF]• Indicates [ON/OFF] condition of SET
lamp determined by the ECM according
to the input signals.
ALT DUTY [%]• Indicates the duty ratio of the power gen-
eration command value. The ratio is cal-
culated by ECM based on the battery
current sensor signal.
BAT CUR SEN [mV]• The signal voltage of battery current sen-
sor is displayed. Monitored item
[Unit]ECM IN-
PUT SIG-
NALSMAIN
SIGNALSDescription Remarks