2004 INFINITI QX56 Light

BRC-8
[VDC/TCS/ABS]
SYSTEM DESCRIPTION
Revision: August 20072004 QX56
ABS FunctionEFS003QJ

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 FunctionEFS003QK

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 FunctionEFS003QL

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 FunctionEFS003QM

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 FunctionEFS003QN
CAUTION:
If the Fail-Safe function is activated, perform the Self Diagnosis for ABS/TCS/VDC system.

DI-1
DRIVER INFORMATION SYSTEM
K ELECTRICAL
CONTENTS
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SECTION DI
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Revision: August 20072004 QX56 PRECAUTION ............................................................ 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 3
Wiring Diagrams and Trouble Diagnosis .................. 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
Circuit Diagram ........................................................ 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 .................... 21Engine Speed Signal Inspection ............................. 21
Fuel 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

DI-2Revision: August 20072004 QX56 CAN Communication System Description .............. 45
Wiring Diagram — CHIME — ................................. 46
Terminals and Reference Value for BCM ................ 48
Terminals and Reference Value for Combination
Meter ...................................................................... 49
How to Proceed With Trouble Diagnosis ................ 49
Preliminary Check .................................................. 49
INSPECTION FOR POWER SUPPLY AND
GROUND CIRCUIT ............................................. 49
CONSULT-II Function (BCM) .................................. 51
CONSULT-II BASIC OPERATION PROCEDURE
... 51
DATA MONITOR .................................................. 52
ACTIVE TEST ..................................................... 52
SELF-DIAGNOSTIC RESULTS ........................... 52
All Warning Chimes Do Not Operate ...................... 53
Key Warning Chime and Light Warning Chime Do
Not Operate (Seat Belt Warning Chime Does Oper-
ate) ......................................................................... 53
Key Warning Chime Does Not Operate .................. 54
Light Warning Chime Does Not Operate ................ 56
Seat Belt Warning Chime Does Not Operate ......... 57
REAR SONAR SYSTEM ........................................... 59
Component Parts and Harness Connector Location ... 59
System Description ................................................. 60
FUNCTION .......................................................... 60
REAR SONAR SYSTEM OFF SWITCH .............. 60
SONAR BUZZER ................................................ 60
REAR SONAR SENSOR ..................................... 61
Wiring Diagram — SONAR — ................................ 62
Terminals And Reference Value For Sonar Control
Unit ......................................................................... 64
How to Proceed With Trouble Diagnosis ................ 64
Pre-diagnosis Inspection ........................................ 65
SENSOR STATUS CHECK ................................. 65
Self-diagnosis Function .......................................... 65
ENTERING DIAGNOSTICS MODE .................... 65
REQUESTING NUMBER OF FAULT CODES
MODE .................................................................. 65
REQUESTING FAULT CODES MODE ............... 66
IDLING OR CLEARING FAULT CODES MODE ... 66
Preliminary Check .................................................. 67INSPECTION FOR POWER SUPPLY AND
GROUND CIRCUIT .............................................67
Symptom Chart .......................................................68
Component Inspection ............................................69
SONAR BUZZER .................................................69
REAR SONAR SYSTEM OFF SWITCH ..............69
REAR SONAR SYSTEM OFF INDICATOR .........69
Removal and Installation of Rear Sonar System ....69
REAR SONAR SENSORS ...................................69
SONAR CONTROL UNIT ....................................69
CLOCK ......................................................................70
Wiring Diagram — CLOCK — .................................70
Removal and Installation of Clock ...........................71
REMOVAL ............................................................71
INSTALLATION ....................................................71
REAR VIEW MONITOR .............................................72
System Description .................................................72
POWER SUPPLY AND GROUND .......................72
AV COMMUNICATION LINE ...............................72
REAR VIEW CAMERA OPERATION ..................72
Component Parts and Harness Connector Location ...73
Schematic ...............................................................74
Wiring Diagram — R/VIEW — ................................75
Terminals and Reference Value for Rear View Cam-
era Control Unit .......................................................78
CONSULT-II Function (REARVIEW CAMERA) ......79
CONSULT-II BASIC OPERATION .......................79
WORK SUPPORT ...............................................80
DATA MONITOR ..................................................80
Side Distance Guideline Correction ........................81
SIDE DISTANCE GUIDELINE CORRECTION
PROCEDURE ......................................................81
Power Supply and Ground Circuit Inspection .........83
Rear View Is Not Displayed With The A/T Selector
Lever In R Position ..................................................84
Removal and Installation of Rear View Camera Con-
trol Unit ....................................................................88
REMOVAL ............................................................88
INSTALLATION ....................................................88
Removal and Installation of Rear View Camera .....88
REMOVAL ............................................................88
INSTALLATION ....................................................88

COMBINATION METERS
DI-5
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Revision: August 20072004 QX56
COMBINATION METERSPFP:24814
System DescriptionEKS007DL
UNIFIED METER CONTROL UNIT

Speedometer, odometer, tachometer, fuel gauge, oil pressure gauge, voltage meter, A/T 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-152,
"System Description" .

DI-12
COMBINATION METERS
Revision: August 20072004 QX56
Terminals and Reference Value for Combination MeterEKS007DQ
Te r m i n a l
No.Wire
colorItemCondition
Reference value (V)
(Approx.) Ignition
switchOperation or condition
1OIgnition switch ACC or
ONACC — Battery voltage
8 Y/R Battery power supply OFF — Battery voltage
11 W C A N - H — — —
12 R CAN-L — — —
15 Y/L Fuel level sensor signal — —Refer to DI-22, "
Fuel Level Sensor
Unit Inspection" .
16 B/PFuel level sensor and oil
pressure sensor groundON — 0V
17 B Ground OFF — 0V
18 BR Illumination control switch — Lighting switch ONRefer to LT-153, "
ILLUMINATION
OPERATION BY LIGHTING
SWITCH" .
20 YOil pressure sensor sig-
nalON — 0 - 5V
22 GR/LOil pressure sensor refer-
ence voltageON — 5V
24 O/LIgnition switch ON or
STARTON — Battery voltage

COMBINATION METERS
DI-13
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Revision: August 20072004 QX56
Meter/Gauge Operation and Odo/Trip MeterEKS007DR
SELF-DIAGNOSIS FUNCTION
The following items can be checked during Combination Meter Self-Diagnosis Mode.

Gauge sweep and present gauge values.

Illuminates all odometer, fuel, and engine temperature segments.

Illuminates all micro controlled lamps/LED's regardless of switch configuration.

Displays estimated present battery voltage.

Displays seat belt buckle switch LH status.
HOW TO INITIATE COMBINATION METER SELF- DIAGNOSIS MODE
NOTE:
Once entered, Combination Meter Self-Diagnosis Mode will function with the ignition switch in ON or START.
Combination Meter Self-Diagnosis Mode will exit upon turning the ignition switch to OFF or ACC.
To initiate Combination Meter Self-Diagnosis Mode, refer to the following procedure.
1. Turn the ignition switch ON, while holding the odometer/trip meter switch for 5 - 8 seconds.
NOTE:
If the diagnosis function is activated the odometer/trip meter will display tESt.
COMBINATION METER SELF-DIAGNOSIS MODE FUNCTIONS
To interpret Combination Meter Self-Diagnosis Mode functions, refer to the following table.
Event Odometer Display Description of Test/Data Notes:
Odometer/trip meter A/B
switch held from 5 to 8
seconds (or until
released)tESt Initiating self-diagnosis mode
Odometer/trip meter A/B
switch engaged and
released = next test
requestedrXXXX, FAILReturn to normal opera-
tion of all lamps/LEDs and
displays hex ROM rev. If
a ROM checksum fault
exists, display alternates
between "r XXXX" and
"FAIL".
Next test requested nrXXXXDisplays hex ROM rev as
stored in NVM.
Next test requested GAGEPerforms sweep of all
gauges, then displays
present gauge values.
Performs checksum tests
on ROM and EE.Gauges sweep within 10 sec-
onds
Next test requested (All segments illuminated)Lights all odometer/trip
meter, fuel, and engine
temperature display seg-
ments.Initiating self-diagnosis mode
complete
Next test requested bulbIlluminates all micro-con-
trolled lamps/LEDs
regardless of SW configu-
ration.
Next test requested EE XX, FAILHex EE level. If EE
checksum fault exists,
display alternates
between "EE XX" and
"FAIL".
Next test requested dtXXXXHex coding of final manu-
facturing test date.

DI-44
WARNING CHIME
Revision: August 20072004 QX56
System DescriptionEKS007EF
FUNCTION
Power is supplied at all times

through 50A fusible link (letter f , located in the fuse and fusible link box)

to BCM terminal 70, and

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

to key switch and key lock solenoid terminal 3.
With ignition switch in ON or START position, power is supplied

through 10A fuse [No. 59, located in the fuse and relay box)

to BCM terminal 38.
Ground is supplied

to BCM terminal 67

through body grounds M57, M61, and M79.
NOTE:
When ignition key warning chime, light warning chime, and seat belt warning chime are required at the same
time, the priorities for each chime are the following.
1. Light warning chime
2. Ignition key warning chime
3. Seat belt warning chime
IGNITION KEY WARNING CHIME
With the key inserted in the ignition switch, the ignition switch in OFF position, and the driver's door open, the
warning chime will sound.
Power is supplied

through key switch and key lock solenoid terminal 4

to BCM terminal 37.
Ground is supplied

to BCM terminal 47

through front door switch LH terminal 2.
Front door switch LH is case grounded.
BCM detects key inserted into the ignition switch, and sends key warning signal to combination meter via CAN
communication lines. When the combination meter receives key warning signal, it sounds warning chime.
LIGHT WARNING CHIME
With the key removed from the ignition switch, the driver's door open, and the lighting switch (part of the com-
bination switch) in 1st or 2nd position, the warning chime will sound. [Except when headlamp battery saver
control operates (5 minutes after ignition switch is turned to OFF or ACC position) and headlamps do not illu-
minate.]
Signal is supplied

from combination switch (lighting switch) terminals 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10

to BCM terminals 2, 3, 4, 5, 6, 32, 33, 34, 35 and 36.
NOTE:
BCM detected lighting switch in 1st or 2nd position. Refer to BCS-3, "
COMBINATION SWITCH READING
FUNCTION" .
Ground is supplied

to BCM terminal 47

through front door switch LH terminal 2.
Front door switch LH is case grounded.
BCM detects headlamps are illuminated, and sends light warning signal to combination meter CAN communi-
cation lines. When the combination meter receives light warning signal, it sounds warning chime.
SEAT BELT WARNING CHIME
When the ignition switch is turned ON with the seat belt unfastened (seat belt buckle switch LH unfastened),
warning chime will sound for approximately 6 seconds.

DI-48
WARNING CHIME
Revision: August 20072004 QX56
Terminals and Reference Value for BCMEKS007EI
Terminal
No.Wire
colorItem Condition
Reference value (V)
(Approx.) Ignition
switchMeasurement method
2 SB Combination switch input 5 ON

Light switch and wiper switch
OFF

Wiper dial position 4
3 G/Y Combination switch input 4 ON

Light switch and wiper switch
OFF

Wiper dial position 4
4 Y Combination switch input 3 ON

Light switch and wiper switch
OFF

Wiper dial position 4
5 G/B Combination switch input 2
ON

Light switch and wiper switch
OFF

Wiper dial position 4 6 V Combination switch input 1
32 R/G Combination switch output 5 ON

Light switch and wiper switch
OFF

Wiper dial position 4
33 R/Y Combination switch output 4 ON

Light switch and wiper switch
OFF

Wiper dial position 4
34 L Combination switch output 3 ON

Light switch and wiper switch
OFF

Wiper dial position 4
SKIA5291E
SKIA5292E
SKIA5291E
SKIA5292E
SKIA5291E
SKIA5292E
SKIA5291E