2006 INFINITI QX56 fuel pressure

ACS-12
[ICC]
LASER BEAM AIMING ADJUSTMENT
Revision: November 20092006 QX56
LASER BEAM AIMING ADJUSTMENTPFP:00026
Outline of Laser Beam Aiming Adjustment ProcedureEKS00BLN
CAUTION:

The laser beam aiming adjustment cannot be performed without CONSULT-II.

The laser beam aiming adjustment must be performed every time the ICC sensor is removed,
installed or has been moved as a result of a collision.
1. Prepare the vehicle and the work area.
2. Set up the ICC target board. For details, refer to Technical Service Bulletin.
3. Adjust the sensor following the procedure on CONSULT-II.
4. Check system operation after the adjustment.
PreparationEKS00BLO

Place the vehicle on level ground. Shift the transmission into "P" position and release the parking brake.

Adjust the tire pressure to the specified value.

See that there is no load in the vehicle. Coolant, engine oil and fuel should be filled to correct level.

Check that the vehicle suspension has been adjusted to the standard height by the load leveling rear air
suspension system. Refer to RSU-12, "
Basic Inspection" .

Clean the sensor with a soft cloth.
Setting up the ICC Target BoardEKS00BLP
CAUTION:
Accuracy in setting up the ICC target board is essential for the laser beam aiming adjustment.
For details, refer to Technical Service Bulletin.
ADJUSTING HEIGHT OF THE TARGET
1. Attach a triangle scale as shown.Tool number : KV99110100 (J-45718)
LKIA0632E
WKIA1849E

A/T CONTROL SYSTEMAT-35
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Revision: November 2009 2006 QX56
Lock-up Applied

In the lock-up applied state, the torque converter clutch control valve is set into the locked state by the
torque converter clutch solenoid and lock-up apply pressure is generated.
In this way, the torque converter clutch piston is pressed and coupled.
SMOOTH LOCK-UP CONTROL
When shifting from the lock-up released state to the lock-up applied state, the current output to the torque con-
verter clutch solenoid is controlled with the TCM. In this way, when shifting to the lock-up applied state, the
torque converter clutch is temporarily set to the half-clutched state to reduce the shock.
Half-clutched State

The current output from the TCM to the torque converter clutch solenoid is varied to gradually increase
the torque converter clutch solenoid pressure.
In this way, the lock-up apply pressure gradually rises and while the torque converter clutch piston is put
into half-clutched status, the torque converter clutch piston operating pressure is increased and the cou-
pling is completed smoothly.
Slip Lock-up Control

In the slip region, the torque converter clutch solenoid current is controlled with the TCM to put it into the
half-clutched state. This absorbs the engine torque fluctuation and lock-up operates from low speed.
This raises the fuel efficiency for 4th and 5th gears at both low speed and when the accelerator has a low
degree of opening.

BRC-8
[VDC/TCS/ABS]
SYSTEM DESCRIPTION
Revision: November 20092006 QX56
ABS FunctionEFS004XC

The Anti-Lock Brake System detects wheel revolution while braking and improves handling stability during
sudden braking by electrically preventing wheel lockup. Maneuverability is also improved for avoiding
obstacles.

If the electrical system malfunctions, the Fail-Safe function is activated, the ABS becomes inoperative and
the ABS warning lamp turns on.

The electrical system can be diagnosed using CONSULT-II.

During ABS operation, the brake pedal may vibrate lightly and a mechanical noise may be heard. This is
normal.

Just after starting the vehicle, the brake pedal may vibrate or a motor operating noise may be heard from
engine compartment. This is a normal status of operation check.

Stopping distance may be longer than that of vehicles without ABS when vehicle drives on rough, gravel,
or snow-covered (fresh, deep snow) roads.
EBD FunctionEFS004XD

Electronic Brake Distribution is a function that detects subtle slippages between the front and rear wheels
during braking, and it improves handling stability by electronically controlling the brake fluid pressure
which results in reduced rear wheel slippage.

If the electrical system malfunctions, the Fail-Safe function is activated, the EBD and ABS become inoper-
ative, and the ABS warning lamp and BRAKE warning lamp are turned on.

The electrical system can be diagnosed using CONSULT-II.

During EBD operation, the brake pedal may vibrate lightly and a mechanical noise may be heard. This is
normal.

Just after starting the vehicle, the brake pedal may vibrate or a motor operating noise may be heard from
engine compartment. This is a normal status of operation check.
TCS FunctionEFS004XE

Spinning of the drive wheels is detected by the ABS actuator and electric unit (control unit) using inputs
from the wheel speed sensors. If wheel spin occurs, the drive wheel right and left brake fluid pressure
control and engine fuel cut are activated while the throttle value is restricted to reduce the engine torque
and decrease the amount of wheel spin. In addition, the throttle opening is controlled to achieve the opti-
mum engine torque.

Depending on road condition, the vehicle may have a sluggish feel. This is normal, because optimum trac-
tion has the highest priority during TCS operation.

TCS may be activated during sudden vehicle acceleration, wide open throttle acceleration, sudden trans-
mission shifts or when the vehicle is driven on a road with a varying surface friction coefficient.

The SLIP indicator lamp flashes to inform the driver of TCS operation.
VDC FunctionEFS004XF

In addition to the ABS/TCS function, the driver steering amount and brake operation amount are detected
from the steering angle sensor and front and rear pressure sensors, and the vehicle's driving status
(amount of under steering/over steering) is determined using inputs from the yaw rate sensor/side G sen-
sor, wheel speed sensors, etc. and this information is used to improve vehicle stability by controlling the
braking and engine torque application to the wheels.

The SLIP indicator lamp flashes to inform the driver of VDC operation.

During VDC operation, the vehicle body and brake pedal may vibrate lightly and a mechanical noise may
be heard. This is normal.

The ABS warning lamp, VDC OFF indicator lamp and SLIP indicator lamp may turn on when the vehicle is
subject to strong shaking or large vibration, such as when the vehicle is on a turn table or a ship while the
engine is running or on a steep slope. In this case, restart the engine on a normal road and if the ABS
warning lamp, VDC OFF indicator lamp and SLIP indicator lamp turn off, there is no problem.
Fail-Safe FunctionEFS004XG
CAUTION:
If the Fail-Safe function is activated, perform the Self Diagnosis for ABS/TCS/VDC system.

BRC-32
[VDC/TCS/ABS]
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
Note 1. If wheel sensor 2 for each wheel is indicated, check ABS actuator and electric unit (control unit) power
supply voltage in addition to wheel sensor circuit check.
Note 2. If multiple malfunctions are detected including CAN communication line [U1000], perform diagnosis for
CAN communication line first.
DATA MONITOR
Operation Procedure
1. After turning OFF the ignition switch, connect CONSULT-II and the CONSULT-II CONVERTER to the data
link connector.
CAUTION:
If CONSULT-II is used with no connection of CONSULT-II CONVERTER, malfunctions might be
detected in self-diagnosis depending on control unit which carries out CAN communication.
2. Touch “START (NISSAN BASED VHCL) ”, “ABS”, “DATA MONITOR ” in order on the CONSULT-II screen.
If “ABS” is not indicated, go to GI-40, "
CONSULT-II Data Link Connector (DLC) Circuit" .
BR FLUID LEVEL LOW
[C1155] Brake fluid level drops or circuit between ABS actuator and elec-
tric unit (control unit) and brake fluid level switch is open or
shorted. BRC-47, "Brake Fluid
Level Switch System
Inspection"
ENGINE SIGNAL 1
[C1130]
Based on the signal from ECM, ABS actuator and electric unit
(control unit) judges that engine fuel cut system is malfunction-
ing.
BRC-39, "
Engine Sys-
tem Inspection"
ENGINE SIGNAL 2
[C1131]Based on the signal from ECM, ABS actuator and electric unit
(control unit) judges that engine fuel cut system is malfunction-
ing.
ENGINE SIGNAL 3
[C1132] Based on the signal from ECM, ABS actuator and electric unit
(control unit) judges that engine fuel cut system is malfunction-
ing.
ENGINE SIGNAL 4
[C1133] Based on the signal from ECM, ABS actuator and electric unit
(control unit) judges that engine fuel cut system is malfunction-
ing.
ENGINE SIGNAL 6
[C1136] Based on the signal from ECM, ABS actuator and electric unit
(control unit) judges that engine fuel cut system is malfunction-
ing.
ACTUATOR RLY
[C1140] ABS actuator relay or circuit malfunction. BRC-44, "
Actuator
Motor, Motor Relay, and
Circuit Inspection"
PRESS SEN CIRCUIT
[C1142]
ABS pressure sensor circuit malfunction.
BRC-51, "Pressure Sen-
sor System Inspection"
VARIANT CODING
[C1170]V coding is not malfunctioning. BRC-40, "ABS/TCS/
VDC Control Unit
Inspection"
ABS ACTIVE BOOSTER SV NG
[C1178]Active booster solenoid is malfunctioning, or signal line of active
booster servo is open or shorted. BRC-48, "Active Booster
System Inspection"
ABS DELTA S SEN NG
[C1179]Delta stroke sensor malfunctioning, or signal line of delta stroke
sensor is open or shorted. BRC-49, "Delta Stroke
Sensor System Inspec-
tion"
ABS ACTIVE BOOSTER
RESPONSE NG
[C1181]Active booster response is malfunctioning, or signal line of active
booster response is open or shorted.
BRC-48, "Active Booster
System Inspection"
ABS BRAKE RELEASE SW NG
[C1184]Brake release switch is malfunctioning, or signal line of brake
release switch is open or shorted. BRC-48, "Active Booster
System Inspection"
ABS ACC CU INTERNAL NG
[C1185]
ICC control unit internal malfunction.
BRC-54, "ICC System
Inspection"
ABS BRAKE BOOSTER DEFECT
[C1189]Brake booster is defective or malfunctioning. BRC-48, "Active Booster
System Inspection"
Self-diagnostic item
Malfunction detecting condition Check system

DI-1
DRIVER INFORMATION SYSTEM
K ELECTRICAL
CONTENTS
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Revision: November 2009 2006 QX56
PRECAUTION .......................................................
..... 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ............................................................. ..... 3
PREPARATION ...................................................... ..... 4
Commercial Service Tool .................................... ..... 4
COMBINATION METERS ...................................... ..... 5
System Description ............................................. ..... 5
UNIFIED METER CONTROL UNIT ................. ..... 5
POWER SUPPLY AND GROUND CIRCUIT ... ..... 6
WATER TEMPERATURE GAUGE ................... ..... 6
ENGINE OIL PRESSURE GAUGE .................. ..... 6
A/T OIL TEMPERATURE GAUGE ................... ..... 6
VOLTAGE GAUGE ........................................... ..... 6
TACHOMETER ................................................ ..... 6
FUEL GAUGE ....................................................... 6
SPEEDOMETER .............................................. ..... 6
CAN COMMUNICATION SYSTEM DESCRIP-
TION ................................................................. ..... 6
Component Parts and Harness Connector Location ..... 7
Combination Meter .............................................. ..... 8
CHECK ............................................................. ..... 8
Schematic ........................................................... ..... 9
Wiring Diagram — METER — ............................. ... 10
Terminals and Reference Value for Combination
Meter ................................................................... ... 12
Meter/Gauge Operation and Odo/Trip Meter ...... ... 13
SELF-DIAGNOSIS FUNCTION ....................... ... 13
HOW TO INITIATE COMBINATION METER
SELF- DIAGNOSIS MODE .............................. ... 13
COMBINATION METER SELF-DIAGNOSIS
MODE FUNCTIONS ........................................ ... 13
How to Proceed With Trouble Diagnosis ............. ... 17
Diagnosis Flow .................................................... ... 17
Power Supply and Ground Circuit Inspection ..... ... 18
Symptom Chart ................................................... ... 19
Vehicle Speed Signal Inspection ......................... ... 19
Engine Oil Pressure Signal Inspection ................ ... 19
Water Temperature Signal Inspection ................. ... 21
Engine Speed Signal Inspection ......................... ... 21Fuel Level Sensor Unit Inspection .......................
... 22
FUEL LEVEL SENSOR UNIT .......................... ... 22
LOW-FUEL WARNING LAMP .......................... ... 22
Fuel Gauge Fluctuates, Indicates Wrong Value, or
Varies ................................................................... ... 24
Fuel Gauge Does Not Move to Full-position ........ ... 24
Electrical Components Inspection ....................... ... 25
FUEL LEVEL SENSOR UNIT CHECK ............. ... 25
Removal and Installation of Combination Meter .. ... 25
COMPASS AND THERMOMETER ........................ ... 26
System Description .............................................. ... 26
OUTSIDE TEMPERATURE DISPLAY .............. ... 26
DIRECTION DISPLAY ...................................... ... 26
Wiring Diagram — COMPAS — .......................... ... 27
Trouble Diagnoses .............................................. ... 28
PRELIMINARY CHECK FOR THERMOMETER ... 28
INSPECTION/COMPASS AND THERMOME-
TER .................................................................. ... 28
Calibration Procedure for Compass .................... ... 29
CORRECTION FUNCTIONS OF COMPASS ... ... 29
INITIAL CORRECTION PROCEDURE FOR
COMPASS ........................................................ ... 30
WARNING LAMPS ................................................. ... 31
Schematic ............................................................ ... 31
Wiring Diagram — WARN — ............................... ... 32
Oil Pressure Warning Lamp Stays Off (Ignition
Switch ON) .......................................................... ... 38
Oil Pressure Warning Lamp Does Not Turn Off (Oil
Pressure Is Normal) ............................................. ... 40
A/T INDICATOR ..................................................... ... 41
Wiring Diagram — AT/IND — .............................. ... 41
A/T Indicator Does Not Illuminate ........................... 42
WARNING CHIME .................................................. ... 43
Component Parts and Harness Connector Location ... 43
System Description .............................................. ... 44
FUNCTION ....................................................... ... 44
IGNITION KEY WARNING CHIME .................. ... 44
LIGHT WARNING CHIME ................................ ... 44
SEAT BELT WARNING CHIME ........................ ... 44
CAN Communication System Description ........... ... 45

COMBINATION METERSDI-5
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COMBINATION METERSPFP:24814
System DescriptionEKS00BBU
UNIFIED METER CONTROL UNIT

Speedometer, odometer, tachometer, fuel gauge, oil pressure gauge, voltage gauge, A/T oil temperature
gauge, and water temperature gauge are controlled by the unified meter control unit, which is built into the
combination meter.

Warning indicators are controlled by signals drawn from the CAN communication system, BCM (body con-
trol module), and components connected directly to the combination meter.

Digital meter is adopted for odometer/trip meters*, as well as the A/T position indicator display.
*The record of the odometer is kept even if the battery cable is disconnected.

Odometer/trip meters and A/T indicator segments can be checked in diagnosis mode.

Meters/gauges can be checked in diagnosis mode.
Illumination control
The unified meter control unit outputs the speedometer, odometer/trip meters, tachometer, oil pressure gauge,
voltage meter, A/T indicator, A/T temperature gauge, fuel and temperature gauge lighting when the ignition
switch is turned on. When the lighting switch is turned on, the illumination control switch can be used to adjust
the brightness of the combination meter illumination and the odometer/trip meters and meter illumination.
When the ignition switch is turned from the OFF to the ON position, the combination meter dial lighting will
remain off for 0.7 seconds. For additional combination meter illumination control information, refer to LT- 1 5 7 ,
"System Description" .

DI-6
COMBINATION METERS
Revision: November 20092006 QX56
POWER SUPPLY AND GROUND CIRCUIT
Power is supplied at all times

through 10A fuse [No.19, located in the fuse block (J/B)]

to combination meter terminal 8.
With the ignition switch in the ON or START position, power is supplied

through 10A fuse [No.14, located in the fuse block (J/B)]

to combination meter terminal 24.
With the ignition switch in the ACC or ON position, power is supplied

through 10A fuse [No.4, located in the fuse block (J/B)]

to combination meter terminal 1.
Ground is supplied

to combination meter terminal 17

through body grounds M57, M61 and M79.
WATER TEMPERATURE GAUGE
The water temperature gauge indicates the engine coolant temperature.
ECM provides an engine coolant temperature signal to combination meter via CAN communication lines.
ENGINE OIL PRESSURE GAUGE
The engine oil pressure gauge indicates the engine oil pressure.
The engine oil pressure gauge is regulated by the unified meter control unit and input from the oil pressure
sensor.
A/T OIL TEMPERATURE GAUGE
The A/T oil temperature gauge indicates the A/T fluid temperature.
TCM (transmission control module) provides an A/T fluid temperature signal to combination meter via CAN
communication lines.
V O LTA G E G A U G E
The voltage gauge indicates the battery/charging system voltage.
The voltage gauge is regulated by the unified meter control unit.
TACHOMETER
The tachometer indicates engine speed in revolutions per minute (rpm).
ECM provides an engine speed signal to combination meter via CAN communication lines.
FUEL GAUGE
The fuel gauge indicates the approximate fuel level in the fuel tank.
The fuel gauge is regulated by the unified meter control unit and a variable resistor signal supplied

to combination meter terminal 15.

through fuel level sensor unit and fuel pump terminal 2

through fuel level sensor unit and fuel pump terminal 5

from combination meter terminal 16
SPEEDOMETER
ABS actuator and electric unit (control unit) provides a vehicle speed signal to the combination meter via CAN
communication lines.
CAN COMMUNICATION SYSTEM DESCRIPTION
Refer to LAN-26, "CAN COMMUNICATION" .

COMBINATION METERSDI-7
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Component Parts and Harness Connector LocationEKS00BBV
1. Fuse block (J/B)2. Combination meter M243. Fuel level sensor unit and fuel pump
C5 (view with inspection hole cover
removed)
4. ECM E16 (view with battery removed) 5. ABS actuator and electric unit (con-
trol unit) E125 6. Oil pressure sensor F4
A. Oil pan (upper)
7. A/T assembly F9
WKIA4591E