INFINITI QX56 2004 Factory User Guide

ACS-2Revision: August 20072004 QX56 DTC 90 STOP LAMP RLY FIX ............................... 43
DTC 92 ECM CIRCUIT ........................................... 47
DTC 96 NP RANGE ............................................... 48
DTC 97 AT CIRCUIT .............................................. 48
DTC 98 GEAR POSITION ...................................... 49
DTC 102 LASER STAIN ......................................... 49
DTC 103 LASER SENSOR FAIL ............................ 50
DTC 104 LASER AIMING INCMP .......................... 50
DTC 107 LASER COMM FAIL ................................ 51
DTC 109 LASER HIGH TEMP ............................... 51
TROUBLE DIAGNOSIS FOR SYMPTOMS .............. 52
Symptom Chart ....................................................... 52
Symptom 1: ON/OFF Switch Does Not Switch ON*
1
, ON/OFF Switch Does Not Switch OFF*
2 .............. 53
Symptom 2: The ICC System Cannot Be Set (ON/
OFF Switch Turns On/Off) ...................................... 53
Symptom 3: The ICC System Cannot Be Operated
by the CANCEL Switch, ACCEL/RES Switch, or DISTANCE Switch ..................................................54
Symptom 4: The ICC System Is Not Cancelled
When the Gear Is in Other Than ‘D’ ........................55
Symptom 5: Chime Does Not Sound ......................55
Symptom 6: Driving Force Is Hunting .....................56
Symptom 7: The ICC System Frequently Cannot
Detect the Vehicle Ahead/The Detection Zone is
Short .......................................................................56
Symptom 8: The System Does Not Detect the Vehi-
cle Ahead at All .......................................................56
ELECTRICAL COMPONENT INSPECTION .............58
ICC Steering Switch ................................................58
ICC Brake Switch and Stop Lamp Switch ...............58
Parking Brake Switch ..............................................58
REMOVAL AND INSTALLATION ..............................59
ICC Unit ..................................................................59
ICC Sensor .............................................................59
ICC Steering Switch ................................................59

AUTOMATIC SPEED CONTROL DEVICE (ASCD)
ACS-3
[ASCD]
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AUTOMATIC SPEED CONTROL DEVICE (ASCD)PFP:18930
DescriptionEKS007NI
Regarding the information for ASCD system, refer to EC-647, "AUTOMATIC SPEED CONTROL DEVICE
(ASCD)" .

ACS-4
[ICC]
PRECAUTIONS
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PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EKS007YA
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WAR NIN G:

To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions for ICC System ServiceEKS007YB

Do not look straight into the laser beam discharger when adjusting laser beam aiming.

Turn the ON/OFF switch OFF during chassis dynamometer testing.

Do not remove, disassemble, or reposition the ICC sensor unless told to do so.

Erase DTC when replacing parts of ICC system, then check the operation of ICC system after adjusting
laser beam aiming if necessary.
Wiring Diagrams and Trouble Diagnosis EKS007YC
When you read wiring diagrams, refer to the following:

Refer to GI-15, "How to Read Wiring Diagrams" in GI section.

Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT" for power distribution circuit in PG section.
When you perform trouble diagnosis, refer to the following:

Refer to GI-11, "HOW TO FOLLOW TEST GROUPS IN TROUBLE DIAGNOSES" in GI section.

Refer to GI-27, "How to Perform Efficient Diagnosis for an Electrical Incident" in GI section.

PREPARATION
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Special Service ToolEKS007YD
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
KV99110100
(J-45718)
ICC target boardPerforming laser beam aiming ad-
justment
PKIA0358J

ACS-6
[ICC]
DESCRIPTION
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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
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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-8
[ICC]
DESCRIPTION
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Switch OperationEKS007RM
The system is operated by a master ON/OFF switch and four control switches, all mounted on the steering
wheel.
ICC System DisplayEKS007RN
No. Switch name Description
1 ACCEL/RES switch Resumes set speed or increases speed incrementally.
2 COAST/SET switch Sets desired cruise speed, reduces speed incrementally.
3 ON/OFF switch Master switch to activate the system.
4 CANCEL switch Deactivates system without erasing set speed.
5 DISTANCE switch Changes the following distance from: Long, Middle, Short.
SKIA5973E
WKIA1977E
No. Component Description
1 Set vehicle speed indicator Indicates the set vehicle speed.
2 Vehicle ahead detection indicator Indicates whether it detects a vehicle ahead.
3 Set distance indicatorDisplay the selected distance between vehicles set with the DISTANCE
switch.
4 Own vehicle indicator Indicates the base vehicle.
5 ON/OFF switch indicator lamp (Green) Indicates that the system is ON.
6Intelligent cruise control system warning
lamp (Orange)The light comes on if there is a malfunction in the ICC system.
7 Cruise set switch indicator lamp Indicates that the conventional cruise control mode is on.

ACTION TEST
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ACTION TESTPFP:00000
ICC System Running TestEKS007YE
VEHICLE-TO-VEHICLE DISTANCE CONTROL MODE
SET CHECKING
1. Press the ON/OFF switch for less than 1.5 seconds.
2. Drive the vehicle between 25 MPH (40 km/h) and 89 MPH (144 km/h).
3. Push the COAST/SET switch.
4. Confirm that the desired speed is set as the COAST/SET switch is released.
NOTE:

When there is no vehicle ahead, drive at the set speed steadily.

When there is a vehicle ahead, control to maintain distance from the vehicle ahead, watching its speed.

The set vehicle speed is displayed on the ICC system indicator in the combination meter.
CHECK FOR INCREASE OF THE CRUISING SPEED
1. Set vehicle-to-vehicle distance control mode at desired speed.
2. Check if the set speed increases by 1 MPH (1 km/h) as ACCEL/RES switch is pushed.
NOTE:
The maximum set speed of the vehicle-to-vehicle distance control mode is 89 MPH (144 km/h).
CHECK FOR DECREASE OF THE CRUISING SPEED
1. Set vehicle-to-vehicle distance control mode at desired speed.
2. Check if the set speed decreases by 1 MPH (1 km/h) as COAST/SET switch is pushed.
NOTE:

Vehicle-to-vehicle distance control mode is automatically turned off when the driving speed lowers to 20
MPH (32 km/h) due to the deceleration of the vehicle ahead.

The minimum set speed of the vehicle-to-vehicle distance control mode is 25 MPH (40 km/h).
CHECK FOR THE CANCELLATION OF VEHICLE-TO-VEHICLE DISTANCE CONTROL MODE
(NORMAL DRIVING CONDITION) IN THE FOLLOWING CASES:
1. When the brake pedal is depressed after the system is turned on.
2. When the A/T select lever is shifted into gears other than “D”, including manual shifts.
3. When the system is turned off.
4. When CANCEL switch is operated.
CHECK FOR RESTORING THE SPEED THAT IS SET BY VEHICLE-TO-VEHICLE DISTANCE
CONTROL MODE BEFORE CANCELLATION
1. Cancel the system by depressing the brake. Then, check that the speed before cancellation is restored
when pressing ACCEL/RES switch with vehicle speed at 25 MPH (40 km/h) or above.
2. Cancel the system by shifting the select lever into other than “D”. Then, check if the speed set before the
cancellation is restored when ACCEL/RES switch is pressed.
3. Check if the speed previously set is restored when ACCEL/RES switch is operated when driving 25 MPH
(40 km/h) or above, after canceling vehicle-to-vehicle distance control mode by operating the CANCEL
switch.
CHECK ON/OFF SWITCH OPERATION
1. Start the engine. Then, check that the following operations are
performed correctly.
2. Vehicle-to-vehicle distance control mode is displayed when ON/
OFF switch is pressed ON. Vehicle-to-vehicle distance control
mode goes off when ON/OFF switch is turned to OFF.
3. Turn off the ignition switch while ON/OFF switch is ON. Turn the
ignition switch back to ON and confirm that CRUISE lamp and
ICC system display are OFF.
WKIA1978E

ACS-10
[ICC]
ACTION TEST
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CHECK FOR ACCEL/RES, COAST/SET, CANCEL SWITCHES
1. Check if ACCEL/RES, COAST/SET, CANCEL switches operate smoothly.
2. Check if switch buttons rebound as the buttons are released.
CHECK FOR DISTANCE SWITCH
1. Start the engine.
2. Press the ON/OFF switch for less than 1.5 seconds.
3. Press the DISTANCE switch.
4. Check if the set distance indicator changes display in order of:
(long)→(middle)→(short).
NOTE:
The set distance indicator shows long immediately after the engine starts.
CONVENTIONAL (FIXED SPEED) CRUISE CONTROL MODE
SET CHECKING
1. Press the ON/OFF switch for more than 1.5 seconds.
2. Drive the vehicle between 25 MPH (40 km/h) and 89 MPH (144 km/h).
3. Push the COAST/SET switch.
4. Confirm that the desired speed is set when the COAST/SET switch is released.
NOTE:

ICC system display in the combination meter shows nothing.
SKIA6178E

ACTION TEST
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CHECK FOR INCREASE OF THE CRUISING SPEED
1. Set the conventional (fixed speed) cruise control mode at desired speed.
2. Check if the set speed increases by 1 MPH (1.6 km/h) as ACCEL/RES switch is pushed.
NOTE:

If the ACCEL/RES switch is held, the vehicle speed increases until the switch is released.

The maximum set speed is 89 MPH (144 km/h).
CHECK FOR DECREASE OF THE CRUISING SPEED
1. Set the conventional (fixed speed) cruise control mode at desired speed.
2. Check if the set speed decreases by 1 MPH (1.6 km/h) as COAST/SET switch is pushed.
NOTE:

Conventional (fixed speed) cruise control mode is automatically turned off when the driving speed lowers
to 20 MPH (32 km/h).

The lowest set speed is 25 MPH (40 km/h).
CHECK FOR THE CANCELLATION OF CONVENTIONAL (FIXED SPEED) CRUISE CONTROL
MODE (NORMAL DRIVING CONDITION) IN THE FOLLOWING CASES:
Refer to ACS-9, "CHECK FOR THE CANCELLATION OF VEHICLE-TO-VEHICLE DISTANCE CONTROL
MODE (NORMAL DRIVING CONDITION) IN THE FOLLOWING CASES:"
CHECK FOR RESTORING THE SPEED THAT IS SET BY CONVENTIONAL (FIXED SPEED)
CRUISE CONTROL MODE BEFORE ICC CANCELLATION
Refer to ACS-9, "CHECK FOR RESTORING THE SPEED THAT IS SET BY VEHICLE-TO-VEHICLE DIS-
TANCE CONTROL MODE BEFORE CANCELLATION"
CHECK ON/OFF SWITCH OPERATION
1. Start the engine. Then, check that the following operations are
performed correctly.
2. CRUISE lamp (green) illuminates and ICC system indicator
goes off when ON/OFF switch is pressed ON for more than 1.5
seconds. The CRUISE lamp goes off when ON/OFF switch is
turned to OFF.
3. Turn off the ignition switch while ON/OFF switch is ON. Turn the
ignition switch back to ON and confirm that CRUISE lamp is
OFF.
CHECK FOR ACCEL/RES, COAST/SET, CANCEL SWITCHES
1. Check if ACCEL/RES, COAST/SET, CANCEL switches operate smoothly.
2. Check if switch buttons rebound as the buttons are released.
WKIA2038E