2004 INFINITI QX56 ESP

AV-76
NAVIGATION SYSTEM
Revision: August 20072004 QX56
TIRE PRESSURE

Pressure indication in psi on the screen indicates that the
pressure is being measured. After a few trips, the pressures for
all four tires will be displayed.

The order of tire pressure figures displayed on the screen does
not correspond with the actual order of tire position.

Tire pressure rises and falls depending on the heat caused by
the vehicle's traveling condition and the temperature.

In case of low tire pressure, the low tire pressure warning light
will come on and/or a warning is displayed on the screen.

FLAT TIRE – very low tire pressure.
NOTE:

In a case of FLAT TIRE pressure, interrupt screen is not shown on the display.

On the screen of TIRE PRESSURE, "FLAT TIRE Check All tires" is displayed.
WARNING INDICATIONS
Warning signal (Door switch signal) is received from BCM through
CAN communication line.
CAN Communication System DescriptionEKS008IM
Refer to LAN-5, "CAN COMMUNICATION" .
WKIA1809E
WKIA1957E
Warning indicatorsWarning lamps in
instrument panelWarning detection and cancel conditions Cases of malfunction
DOOR OPEN DoorDetection conditionVehicle is running [approx. 5 km/h
(3 MPH) or faster] and door ajar of
any of the doors is detected.
Door is open
Cancel conditionVehicle is stopped and all the
doors lock.

AV-112
NAVIGATION SYSTEM
Revision: August 20072004 QX56
NAVIGATION
1. The navigation screen will be shown, and items “Display Longi-
tude & Latitude”, “Speed Calibration”, “Angle Adjustment” and
“Initialize Location” will become selective.
2. Select each switch on “NAVIGATION” screen to display the rele-
vant diagnosis screen.
GPS RTC
malfunctionClock IC in GPS substrate is malfunctioning.

Correct time may not be displayed.

After the power is turned on, the system
always takes some time until GPS positioning
becomes possible. (The GPS receiver starts
positioning without re-collecting the whole sat-
ellite information when it judged the data
stored in the receiver is correct.)

Correct time of error occurrence may not be
stored in the ″History of Errors″.

Perform self-diagnosis.

When the NAVI control unit is judged normal by self-diagnosis,
the symptom may be intermittent, caused by strong radio inter-
ference.
GPS antenna
disconnectedMalfunctioning connection between GPS substrate in NAVI control
unit and GPS antenna.

Navigation location detection performance
has deteriorated.
(Location correction using GPS is not per-
formed.)

GPS receiving status remains gray.

Perform self-diagnosis.

When connection between NAVI control unit and GPS antenna
is judged normal by self-diagnosis, the symptom may be inter-
mittent, caused by impact or vibration.
Low voltage
of GPSThe power voltage supplied to the GPS circuit board has
decreased.

Navigation location detection performance
has deteriorated.
(Location correction using GPS is not per-
formed.)

GPS receiving status remains gray.

Perform self-diagnosis.

When connection between NAVI control unit and GPS antenna
is judged normal by self-diagnosis, the symptom may be inter-
mittent, caused by impact or vibration.
DVD-ROM
Malfunction
DVD-ROM
Read error
DVD-ROM
Response
ErrorMalfunctioning NAVI control unit. -
Dedicated map DVD-ROM is in the system, but the data cannot be
read.

The map of a particular location cannot be dis-
played.

Specific guidance information cannot be dis-
played.

Map display is slow.

Guidance information display is slow.

System has been affected by vibration.

Is map DVD-ROM damaged, warped, or dirty?
–If damaged or warped, the map DVD-ROM is malfunctioning.
–If dirty, wipe the DVD-ROM clean with a soft cloth.

Perform self-diagnosis.

When NAVI control unit is judged normal by self-diagnosis, the
symptom is judged intermittent, caused by vibration. Error itemPossible causes
Example of symptom
Action/symptom
SKIA4576E

BCM (BODY CONTROL MODULE)
BCS-3
C
D
E
F
G
H
I
J
L
MA
B
BCS
Revision: August 20072004 QX56
BCM (BODY CONTROL MODULE)PFP:284B2
System DescriptionEKS007GE

BCM (body control module) controls the operation of various electrical units installed on the vehicle.
BCM FUNCTION
BCM has a combination switch reading function for reading the operation of combination switches (light, wiper
washer, turn signal) in addition to the function for controlling the operation of various electrical components.
Also, it functions as an interface that receives signals from the front air control, and sends signals to ECM
using CAN communication.
COMBINATION SWITCH READING FUNCTION
1. Description

BCM reads combination switch (light, wiper) status, and controls various electrical components accord-
ing to the results.

BCM reads information of a maximum of 20 switches by combining five output terminals (OUTPUT 1-5)
and five input terminals (INPUT 1-5).
2. Operation description

BCM activates transistors of output terminals (OUTPUT 1-5) periodically and allows current to flow in
turn.

If any (1 or more) of the switches are turned ON, circuit of output terminals (OUTPUT 1-5) and input ter-
minals (INPUT 1-5) becomes active.

At this time, transistors of output terminals (OUTPUT 1-5) are activated to allow current to flow. When
voltage of input terminals (INPUT 1-5) corresponding to that switch changes, interface in BCM detects
voltage change and BCM determines that switch is ON.
3. BCM - Operation table of combination switch

BCM reads operation status of combination switch by the combination shown in the following table.
LIIA0757E

BL-6
SQUEAK AND RATTLE TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
SQUEAK AND RATTLE TROUBLE DIAGNOSISPFP:00000
Work FlowEIS0 02 R1
CUSTOMER INTERVIEW
Interview the customer if possible, to determine the conditions that exist when the noise occurs. Use the Diag-
nostic Worksheet during the interview to document the facts and conditions when the noise occurs and any
customer's comments; refer BL-10, "
Diagnostic Worksheet" . This information is necessary to duplicate the
conditions that exist when the noise occurs.

The customer may not be able to provide a detailed description or the location of the noise. Attempt to
obtain all the facts and conditions that exist when the noise occurs (or does not occur).

If there is more than one noise in the vehicle, be sure to diagnose and repair the noise that the customer
is concerned about. This can be accomplished by test driving the vehicle with the customer.

After identifying the type of noise, isolate the noise in terms of its characteristics.The noise characteristics
are provided so the customer, service adviser and technician are all speaking the same language when
defining the noise.

Squeak —(Like tennis shoes on a clean floor)
Squeak characteristics include the light contact/fast movement/brought on by road conditions/hard sur-
faces = higher pitch noise/softer surfaces = lower pitch noises/edge to surface = chirping

Creak—(Like walking on an old wooden floor)
Creak characteristics include firm contact/slow movement/twisting with a rotational movement/pitch
dependent on materials/often brought on by activity.

Rattle—(Like shaking a baby rattle)
Rattle characteristics include the fast repeated contact/vibration or similar movement/loose parts/missing
clip or fastener/incorrect clearance.

Knock —(Like a knock on a door)
Knock characteristics include hollow sounding/sometimes repeating/often brought on by driver action.

Tick—(Like a clock second hand)
Tick characteristics include gentle contacting of light materials/loose components/can be caused by driver
action or road conditions.

Thump—(Heavy, muffled knock noise)
Thump characteristics include softer knock/dead sound often drought on by activity.

Buzz—(Like a bumble bee)
Buzz characteristics include high frequency rattle/firm contact.

Often the degree of acceptable noise level will vary depending upon the person. A noise that you may
judge as acceptable may be very irritating to the customer.

Weather conditions, especially humidity and temperature, may have a great effect on noise level.
SBT 8 42

BL-66
REMOTE KEYLESS ENTRY SYSTEM
Revision: August 20072004 QX56
2. CHECK KEYFOB FUNCTION
With CONSULT-II
Check keyfob function in “DATA MONITOR” mode with CONSULT-II.
When pushing each button of keyfob, the corresponding monitor item should
be turned as follows.
Without CONSULT-II
Check keyfob function using Remote Keyless Entry Tester J-43241.
OK or NG
OK >> WITH CONSULT-II: Keyfob, remote keyless entry receiver and wiring harness between BCM and
remote keyless entry receiver are OK. Replace BCM. Refer to BCS-19, "
Removal and Installation
of BCM" .
OK >> WITHOUT CONSULT-II: Keyfob is OK. Further inspection is necessary. Refer to BL-60, "
Trouble
Diagnoses" .
NG >> WITH CONSULT-II: Further inspection is necessary. Refer to BL-60, "
Trouble Diagnoses" .
NG >> WITHOUT CONSULT-II: Replace keyfob. Refer to BL-71, "
ID Code Entry Procedure" .
Remote Keyless Entry Receiver System CheckEIS005X1
1. REMOTE KEYLESS ENTRY RECEIVER SIGNAL
Check signal voltage waveform between BCM connector M18 termi-
nal 20 and ground using an oscilloscope.
OK or NG
OK >> Remote keyless entry receiver signal power supply, ground and signal circuits are OK. Replace
BCM. Refer to BCS-19, "
Removal and Installation of BCM" .
NG >> GO TO 2.Condition Monitor item
Pushing LOCK KEYLESS LOCK : ON
Pushing UNLOCK KEYLESS UNLOCK : ON
Keep pushing UNLOCKRKE KEEP UNLK
turns to ON 3 seconds
after UNLOCK button
is pushed.
Pushing PANIC KEYLESS PANIC : ON
Pushing LOCK and UNLOCK
at the same timeRKE LCK-UNLCK : ON
Pushing Power Back Door KEYLESS PBD : ON
LIIA1487E
Condition:
Keyfob buttons released : Refer to BL-53, "
Te r m i -
nals and Reference Value
for BCM" .
Keyfob buttons pressed : Refer to BL-53, "
Te r m i -
nals and Reference Value
for BCM" .LIIA1275E

AUTOMATIC BACK DOOR SYSTEM
BL-115
C
D
E
F
G
H
J
K
L
MA
B
BL
Revision: August 20072004 QX56
Trouble Diagnosis ProcedureEIS002T0
1. Check the symptom and customer's requests.
2. Understand outline of system. Refer to BL-45, "
System Description" .
3. Confirm system operation.
4. Perform self-diagnosis procedures. Refer to BL-115, "
Self-Diagnosis Procedures" .
5. Refer to diagnosis chart by symptom, repair or replace any malfunctioning parts. Refer to BL-116, "
Diag-
nosis Chart" .
6. Inspection End.
Self-Diagnosis ProceduresEIS005X4
INPUT SIGNAL CHECK MODE
Input signal check mode allows testing of switch input signal to the back door control unit.
To activate input signal check mode on the automatic back door, perform the following steps:
1. Turn ignition switch OFF.
2. Turn back door close switch to CANCEL (system cancelled).
3. Place A/T selector lever in P position.
4. Using the inside emergency release lever, open the back door.
5. Have an assistant press and hold the back door handle switch.
6. While the assistant continues to hold the back door handle switch, turn ignition switch ON (DO NOT start
engine).
7. After approximately 5 seconds, the back door warning chime will sound for 0.5 seconds.
8. Release the back door handle switch.
9. Within 8 seconds of the back door warning chime sounding, press and hold the power liftgate switch.
10. After approximately 5 seconds, the back door warning chime will sound for 1 second.
11. Release the power liftgate switch.
12. The input signal check mode is now initialized.
The input signal check mode can test the following inputs. The back door warning chime will sound for approx-
imately 0.5 seconds each time a switch signal input occurs. Use this test when one of these inputs is not
responding during normal automatic back door operation.
*Back door warning chime should sound as soon as vehicle moves.
Turn ignition switch OFF to end input signal check mode.
OPERATING CHECK MODE
Operating check mode allows self-diagnosis of the automatic back door system.
To activate operating check mode on the automatic back door, perform the following steps:
1. Turn ignition switch OFF.
2. Turn back door close switch to CANCEL (system cancelled).
3. Place A/T selector lever in P position.
Switch signal Operation Refer to
Power liftgate switch OFF → ONBL-118
Back door close switch (CLOSE) OFF → ONBL-120
Back door close switch (CANCEL) OFF → ONBL-121
Back door handle switch OFF → ONBL-127
Glass switch OFF → ONBL-36
A/T device (park switch) P position → other than P positionAT- 1 9 1
Vehicle speed* Vehicle speedAT-6 8
Remote keyless entry signal Keyfob switch OFF → ONBL-66
Door lock/unlock signal LOCK → UNLOCKBL-34
Pinch strip LH signal OFF → ONBL-122
Pinch strip RH signal OFF → ONBL-122

BR-20
VACUUM LINES
Revision: August 20072004 QX56
VACUUM LINESPFP:41920
Removal and InstallationEFS003PL
1. Disconnect vacuum hose from hose clip.
2. Release clamps and disconnect vacuum hose.
3. Remove check valve from brake booster.
4. Installation is in the reverse order of removal.
CAUTION:

Insert vacuum hose for at least 24 mm (0.94 in).

Do not use lubricating oil during assembly.
InspectionEFS003PM
VISUAL INSPECTION
Check for improper assembly, damage and deterioration.
CHECK VALVE INSPECTION
Airtightness Inspection
Use a suitable vacuum pump to check. Connect to brake booster
side of check valve.
1. Hose clip 2. Clamp 3. Vacuum hose
4. Check valve
LFIA0216E
SBR2 25 B
Check
valve
specifi-
cation: Vacuum decrease should be within 1.3
kPa (10 mmHg, 0.39 inHg) for 15 seconds
under a vacuum of – 66.7 kPa (– 500 mmHg,
– 19.69 inHg)
LFIA0217E

TROUBLE DIAGNOSIS
BRC-11
[VDC/TCS/ABS]
C
D
E
G
H
I
J
K
L
MA
B
BRC
Revision: August 20072004 QX56
TROUBLE DIAGNOSISPFP:00000
How to Perform Trouble Diagnoses for Quick and Accurate RepairEFS003QQ
INTRODUCTION
The ABS/TCS/VDC system has an electronic control unit to control
major functions. The control unit accepts input signals from sensors
and controls actuator operation. It is also important to check for con-
ventional problems such as air leaks in the booster or lines, lack of
brake fluid, or other problems with the brake system.
It is much more difficult to diagnose a problem that occurs intermit-
tently rather than continuously. Most intermittent problems are
caused by poor electrical connections or faulty wiring. In this case,
careful checking of suspicious circuits may help prevent the replace-
ment of good parts.
A visual check only may not find the cause of the problem, so a road
test should be performed.
Before undertaking actual checks, take just a few minutes to talk with
a customer who approaches with an ABS/TCS/VDC complaint. The
customer is a very good source of information on such problems,
especially intermittent ones. Through the talks with the customer,
find out what symptoms are present and under what conditions they
occur.
Start your diagnosis by looking for “conventional” problems first. This
is one of the best ways to troubleshoot brake problems on an ABS/
TCS/VDC equipped vehicle. Also check related Service Bulletins for
information.
SEF 2 33 G
SEF 2 34 G