2004 INFINITI QX56 speed sensor

ACS-1
AUTO CRUISE CONTROL SYSTEM
K ELECTRICAL
CONTENTS
C
D
E
F
G
H
I
J
L
M
SECTION ACS
A
B
ACS
Revision: August 20072004 QX56
ASCD
AUTOMATIC SPEED CONTROL DEVICE (ASCD) ..... 3
Description ............................................................... 3
ICC
PRECAUTIONS .......................................................... 4
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 4
Precautions for ICC System Service ........................ 4
Wiring Diagrams and Trouble Diagnosis .................. 4
PREPARATION ........................................................... 5
Special Service Tool ................................................. 5
DESCRIPTION ............................................................ 6
Outline ...................................................................... 6
VEHICLE-TO-VEHICLE DISTANCE CONTROL
MODE ................................................................... 6
CONVENTIONAL (FIXED SPEED) CRUISE
CONTROL MODE ................................................. 6
BRAKE ASSIST (WITH PREVIEW FUNCTION) ..... 6
System Diagram ....................................................... 7
Components Description .......................................... 7
CAN Communication ................................................ 7
SYSTEM DESCRIPTION ...................................... 7
Switch Operation ...................................................... 8
ICC System Display ................................................. 8
ACTION TEST ............................................................ 9
ICC System Running Test ........................................ 9
VEHICLE-TO-VEHICLE DISTANCE CONTROL
MODE ................................................................... 9
CONVENTIONAL (FIXED SPEED) CRUISE
CONTROL MODE ............................................... 10
LASER BEAM AIMING ADJUSTMENT ................... 12
Outline of Laser Beam Aiming Adjustment Proce-
dure ........................................................................ 12
Preparation ............................................................. 12
Setting up the ICC Target Board ............................ 12
ADJUSTING HEIGHT OF THE ICC TARGET
BOARD ............................................................... 12ADJUSTING THE POSITION OF THE ICC TAR-
GET BOARD STRING ......................................... 13
POSITIONING THE ICC TARGET BOARD ........ 13
Sensor Adjustment ................................................. 14
CHECK AFTER THE ADJUSTMENT .................. 17
ELECTRICAL UNITS LOCATION ............................ 18
Component Parts and Harness Connector Location ... 18
WIRING DIAGRAM ................................................... 19
Schematic ............................................................... 19
Wiring Diagram — ICC — ...................................... 20
TERMINALS AND REFERENCE VALUE ................. 25
Terminals and Reference Values for ICC Unit ........ 25
Terminals and Reference Values for ICC Sensor ... 25
TROUBLE DIAGNOSIS — GENERAL DESCRIP-
TION .......................................................................... 26
Work Flow ............................................................... 26
CONSULT-II Function (ICC) ................................... 27
CONSULT-II OPERATION ................................... 27
WORK SUPPORT ............................................... 28
SELF-DIAGNOSTIC RESULTS ........................... 28
DATA MONITOR ................................................. 29
ACTIVE TEST ..................................................... 30
Self-Diagnostic Function ......................................... 32
WITH CONSULT-II .............................................. 32
WITHOUT CONSULT-II ....................................... 32
SELF-DIAGNOSIS BY ICC SYSTEM DISPLAY
WILL NOT RUN ................................................... 34
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC
ITEMS ........................................................................ 36
Diagnostic Trouble Code (DTC) Chart ................... 36
DTC 11 CONTROL UNIT ....................................... 37
DTC 12 VDC CONTROL UNIT ............................... 37
DTC 20 CAN COMM CIRCUIT ............................... 38
DTC 31 POWER SUPPLY CIR 1, DTC 34 POWER
SUPPLY CIR 2 ....................................................... 38
DTC 41 VHCL SPEED SE CIRC ............................ 39
DTC 43 VDC/TCS/ABS CIRC ................................ 39
DTC 45 BRAKE SW/STOP L SW ........................... 40
DTC 46 OPERATION SW CIRC ............................. 41
DTC 74 LASER BEAM OFF CENTER ................... 42

ACS-6
[ICC]
DESCRIPTION
Revision: August 20072004 QX56
DESCRIPTIONPFP:00000
OutlineEKS007RI
The Intelligent Cruise Control (ICC) system automatically maintains a selected distance from the vehicle
ahead according to that vehicle's speed, or at the set speed, if the road ahead is clear.
The ICC function has two cruise control modes and brake assist (with preview function). The ICC system may
AUTO-CANCEL for various reasons, for example, when the windshield wipers are operated at the low speed
(LO) or high speed (HI) position.
VEHICLE-TO-VEHICLE DISTANCE CONTROL MODE
Vehicle-to-vehicle distance control mode, the same speed as other vehicles, can be maintained without the
constant need to adjust the operating speed as with a conventional cruise control system.
The system is intended to enhance the operation of the vehicle when following another vehicle in the same
lane and direction.
If the distance sensor detects a slower moving vehicle ahead, the system will reduce speed so that the vehicle
ahead can be followed at the selected distance.
The system automatically controls the throttle and applies the brakes (up to 25% of vehicle braking power) if
necessary.
The detection range of the sensor is approximately 390 ft (120 m) ahead.
Refer to Owner's Manual for Intelligent Cruise Control System operating instructions.
CONVENTIONAL (FIXED SPEED) CRUISE CONTROL MODE
Conventional (fixed speed) cruise control mode is cruising at preset speeds.
Refer to Owner's Manual for Intelligent Cruise Control System operation instructions.
BRAKE ASSIST (WITH PREVIEW FUNCTION)
When the force applied to brake pedal exceeds a certain level, the brake assist is activated and generates a
greater braking force than that of a conventional brake booster, even with light pedal force.
When the preview function identifies the need to apply the sudden brake by sensing the vehicle ahead in the
same lane and the distance and relative speed from it, it applies the brake pre-pressure before driver
depresses the brake pedal and improves brake response by reducing its free play.
Refer to Owner's Manual for Intelligent Cruise Control System operating instructions.

DESCRIPTION
ACS-7
[ICC]
C
D
E
F
G
H
I
J
L
MA
B
ACS
Revision: August 20072004 QX56
System DiagramEKS007RJ
Components DescriptionEKS007RK
CAN CommunicationEKS007RO
SYSTEM DESCRIPTION
Refer to LAN-5, "CAN COMMUNICATION" .
WKIA1976E
ComponentVehicle-to-vehicle
distance control
modeConventional
(fixed speed)
cruise control
modeBrake assist
(with preview
brake)Description
ICC unit×××Controls vehicle speed through ECM via CAN
communication.
ICC sensor××Irradiate laser beam, and receives reflected
laser beam to measure distance from preceding
vehicle.
ECM××Transmits throttle position signal and ICC steer-
ing switch signal to ICC unit.
ABS actuator and electric
unit (control unit)×××Transmits wheel speed signal to ICC unit.
Operates brake booster based on CAN commu-
nication.
Brake pressure sensor××Detects fluid pressure in master cylinder.
Brake booster××Adjusts brake fluid pressure based on command
from ABS actuator and electric unit (control
unit).
BCM×Transmit front wiper request signal to ICC unit.
TCM××Transmits gear position signal and output shaft
revolution signal to ICC unit.

ACS-28
[ICC]
TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
Revision: August 20072004 QX56
6. Touch “WORK SUPPORT”, “SELF-DIAG RESULTS”, “DATA
MONITOR”, "CAN DIAG SUPPORT MNTR", “ACTIVE TEST” or
“ECU PART NUMBER” on selection screen.
WORK SUPPORT
Work Item
Cause of Auto-Cancel
1. Touch “WORK SUPPORT” on the "SELECT DIAG MODE"
screen.
2. Touch “CAUSE OF AUTO-CANCEL” on the "SELECT WORK
ITEM screen.
3. Cause of automatic cancellation screen will be shown.
4. The last five causes of automatic cancellation of ICC system will
be displayed.
Possible Causes of "Auto-Cancel"
Laser Beam Adjust
For details, refer to ACS-12, "LASER BEAM AIMING ADJUSTMENT" .
SELF-DIAGNOSTIC RESULTS
For details, refer to ACS-36, "Diagnostic Trouble Code (DTC) Chart" .
WKIA2041E
Operation Function
CAUSE OF AUTO-CANCEL Indicates causes of automatic cancellation of the ICC system.
LASER BEAM ADJUST Outputs laser beam, calculates dislocation of the beam, and indicates adjustment direction.
SKIA6191E
Cause of cancellation Description
OPERATING WIPER Windshield wipers were operated at HI or LO speed operation.
OPERATING ABS ABS function was operated.
OPERATING TCS TCS function was operated.
OPERATING VDC VDC function was operated.
OPE SW VOLT CIRC Voltage outside the standard was detected.
LASER SUN BEAM Intense light such as sunlight entered ICC sensor light sensing part.
LASER TEMP Temperature around ICC sensor became low.
OP SW DOUBLE TOUCH ICC steering switches were pressed at the same time.
VDC/TCS OFF SW VDC OFF switch was pressed.
WHEEL SPD UNMATCH Wheel speed became different from AT vehicle speed.
TIRE SLIP Wheel slipped.
PKB SW ON Parking brake is applied.
IGN LOW VOLT Power supply voltage became low.
NO RECORD —

TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
ACS-29
[ICC]
C
D
E
F
G
H
I
J
L
MA
B
ACS
Revision: August 20072004 QX56
DATA MONITOR
Operation Procedure
1. Touch “DATA MONITOR” on the "SELECT DIAG MODE"
screen.
2. Touch “ECU INPUT SIGNALS”, “MAIN SIGNALS“, or “SELEC-
TION FROM MENU” on "SELECT MONITOR ITEM" screen.
Monitored Item
×: Applicable
WDIA0084E
Monitored Item [unit] MAIN SIGNALSECU
INPUT
SIGNALSSELECTION
FROM MENUDescription
VHCL SPEED SE
[km/h] or [mph]×××Indicates vehicle speed calculated from wheel
speed sensor signal.
SET VHCL SPD
[km/h] or [mph]××Indicates set vehicle speed stored in ICC unit.
THRTL OPENING
[%]×××Indicates throttle angle calculated from signal volt-
age of throttle position sensor.
ENGINE RPM
[rpm]××Indicates engine speed read by ICC unit via CAN
communication (ECM transmits engine speed via
CAN communication).
DISTANCE ADJ
[SHOR/MID/LONG]×××Indicates set distance stored in ICC unit.
WIPER SW
[OFF/LOW/HIGH]××Indicates wiper [OFF/LOW/HIGH] status.
MAIN SW
[ON/OFF]×××Indicates [ON/OFF] status as judged from control
switch signal.
SET/COAST SW
[ON/OFF]×××Indicates [ON/OFF] status as judged from control
switch signal.
CANCEL SW
[ON/OFF]×××Indicates [ON/OFF] status as judged from control
switch signal.
RESUME/ACC SW
[ON/OFF]×××Indicates [ON/OFF] status as judged from control
switch signal.
CRUISE OPE
[ON/OFF]××Indicates whether vehicle speed is being con-
trolled or not (ON means “controlling”).
BRAKE SW
[ON/OFF]×××Indicates [ON/OFF] status as judged from ICC
brake switch signal.
STOP LAMP SW
[ON/OFF]×××Indicates [ON/OFF] status as judged from stop
lamp switch signal.
RELEASE SW NO
[ON/OFF]
××Indicates [ON/OFF] status as judged from release
switch signal.
ON when brake is depressed.
OFF when brake is not depressed.
RELEASE SW NC
[ON/OFF]
××Indicates [ON/OFF] status as judged from release
switch signal.
OFF when brake is depressed.
ON when brake is not depressed.
IDLE SW
[ON/OFF]××Indicates [ON/OFF] status of idle switch read by
ICC unit via CAN communication (ECM transmits
ON/OFF status via CAN communication).

ACS-30
[ICC]
TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
Revision: August 20072004 QX56
ACTIVE TEST
CAUTION:
Do not perform the active test while driving. Active test cannot be started while ICC system warning
indicator is illuminated.
Active Test
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.
GEAR
[1, 2, 3, 4, 5]××Indicates AT gear position read by ICC unit via
CAN communication (TCM transmits gear position
via CAN communication).
BUZZER O/P
[ON/OFF] ×Indicates [ON/OFF] status of ICC warning output.
ICC WARNING×NOTE:
This item is displayed but cannot be monitored.
VHCL SPD AT
[km/h] or [mph]
×Indicates vehicle speed calculated from AT vehicle
speed sensor by ICC unit via CAN communication
(TCM transmits AT vehicle speed sensor signal via
CAN communication).
PRESS SENS
[bar]×××Indicates brake fluid pressure value calculated
from signal voltage of pressure sensor.
PRESS SENS 2
[bar]××NOTE:
This item is displayed but cannot be monitored.
D RANGE SW
[ON/OFF]
××Indicates [ON/OFF] status of “D” position read by
ICC unit via CAN communication (TCM transmits
ON/OFF condition of “D” position via CAN commu-
nication).
AT OD OFF
[ON/OFF]×Indicates [ON/OFF] status of OD cancel output
under control.
NP RANGE SW
[ON/OFF]××Indicates PNP switch signal read by ICC unit via
CAN communication. (TCM transmits PNP switch
signal via CAN communication)
DISTANCE×NOTE:
This item is displayed but cannot be monitored.
RELATIVE SPD×NOTE:
This item is displayed but cannot be monitored.
STP LMP DRIVE
[ON/OFF]××Indicates [ON/OFF] status of brake hold relay drive
output. Monitored Item [unit] MAIN SIGNALSECU
INPUT
SIGNALSSELECTION
FROM MENUDescription
SKIA6195E

ACS-36
[ICC]
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
Revision: August 20072004 QX56
TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMSPFP:00000
Diagnostic Trouble Code (DTC) ChartEKS007X2
×: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
assist
(with pre-
view
function)
11 CONTROL UNIT××××

ICC unit internal malfunctionACS-37
12 VDC CONTROL UNIT××××

VDC malfunction

Brake booster signal harness is
open or shortedACS-37
20 CAN COMM CIRCUIT××××
ICC unit detected CAN communi-
cation malfunctionACS-38
31 POWER SUPPLY CIR1××××
ICC unit power supply voltage is
excessively low (less than 8V)ACS-38
34 POWER SUPPLY CIR2××××
ICC unit power supply voltage is
excessively high.ACS-38
41 VHCL SPEED SE CIRC××××

Wheel sensor malfunction

ABS actuator and electric unit
(control unit) malfunction

AT vehicle speed sensor mal-
function

TCM malfunctionACS-39
43 VDC/TCS/ABS CIRC××××
VDC/TCS/ABS system malfunc-
tionACS-39
45 BRAKE SW/ STOP L SW××××

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-40
46 OPERATION SW CIRC×××

ICC steering switch harness or
spiral cable is open or shorted

ICC steering switch malfunctionACS-41
74 LASER BEAM OFF CNTR×× ×
Laser beam of ICC sensor is off
the aiming pointACS-42
90 STOP LAMP RLY FIX×× ×
Normally open terminal of stop
lamp relay is stuckACS-43
92 ECM CIRCUIT××××

ECM malfunction

Accelerator pedal position sensor
malfunction

ICC unit malfunctionACS-47
96 NP RANGE×××

Park/neutral position switch har-
ness is open or shorted

Park/neutral position switch mal-
function

TCM malfunctionACS-48
97 AT CIRCUIT××
TCM malfunctionACS-48

TROUBLE DIAGNOSIS FOR SELF-DIAGNOSTIC ITEMS
ACS-37
[ICC]
C
D
E
F
G
H
I
J
L
MA
B
ACS
Revision: August 20072004 QX56
DTC 11 CONTROL UNITEKS007X3
1. DIAGNOSTIC CHECK
1. Are any items other than “DTC 11 CONTROL UNIT” indicated on self-diagnosis display?
YES or NO
YES >> Repair or replace applicable item. Erase DTC and perform ICC system running test. Then perform
self-diagnosis of ICC system again.
NO >> Replace ICC unit. Refer to ACS-59, "
ICC Unit" . Erase DTC and perform ICC system running
test. Then perform self-diagnosis of ICC system again.
DTC 12 VDC CONTROL UNITEKS008DH
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 applicable item. Erase DTC and perform ICC system running test. Then per-
form 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 connectors of ICC unit and ABS actuator and electric unit (control unit), and connect them
securely again. Then 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 col-
lapsed terminals. If any malfunction is detected, repair applicable part. After repair, erase DTC
and perform ICC system running test. Then perform self-diagnosis of ICC system again.
NG >> GO TO 3.
98 GEAR POSITION××

TCM malfunction

AT turbine revolution sensor mal-
function

AT vehicle speed sensor mal-
functionACS-49
102 LASER STAIN×× ×
ICC sensor body window has
contaminationACS-49
103 LASER SENSOR FAIL×× ×
ICC sensor internal malfunctionACS-50
104 LASER AIMING INCMP×× ×
Laser beam aiming of ICC sensor
is not adjustedACS-50
107 LASER COMM FAIL×× ×

CAN data received by ICC sen-
sor is strange (from ICC unit,
combination meter or ECM)ACS-51
109 LASER HIGH TEMP×× ×
Temperature around ICC sensor
is excessively highACS-51
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
assist
(with pre-
view
function)