2008 INFINITI QX56 light

HAC-4
< BASIC INSPECTION >[AUTOMATIC AIR CONDITIONER]
INSPECTION AND ADJUSTMENT
INSPECTION AND ADJUSTMENT
Operational Check (Front)INFOID:0000000001679764
The purpose of the operational check is to
confirm that the system operates properly.
CHECKING MEMORY FUNCTION
1. Set the temperature to 32 °C (90 °F).
2. Press the OFF switch.
3. Turn ignition switch OFF.
4. Turn ignition switch ON.
5. Press the AUTO switch.
6. Confirm that the set temperature remains at previous temperature.
7. Press the OFF switch.
If NG, go to trouble diagnosis procedure for HAC-121, "
Memory Function Check".
If OK, continue with next check.
CHECKING BLOWER
1. Press the blower speed control switch (+) once, blower should operate on low speed. The fan display should have one bar lit (on display).
2. Press the blower speed control switch (+) again, and continue checking blower speed and fan display until
all speeds are checked.
3. Leave blower on maximum speed.
If NG, go to trouble diagnosis procedure for HAC-51, "
Front Blower Motor Diagnosis Procedure".
If OK, continue with next check.
CHECKING DISCHARGE AIR
1. Press MODE switch four times and the DEF switch.
2. Each position indicator should change shape (on display).
3. Confirm that discharge air comes out according to the air distribution table. Refer to HAC-15, "
Discharge
Air Flow (Front)".
Mode door position is checked in the next step.
If NG, go to trouble diagnosis procedure for HAC-26, "
Mode Door Motor (Front) Diagnosis Procedure".
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual inspection) and intake door position is at
fresh when the DEF or D/F is selected.
CHECKING RECIRCULATION ( , ONLY)
1. Press recirculation ( ) switch one time. Recirculation indicator should illuminate.
2. Press recirculation ( ) switch one more time. Recirculation indicator should go off.
3. Listen for intake door position change (blower sound should change slightly).
If NG, go to trouble diagnosis procedure for HAC-42, "
Intake Door Motor Diagnosis Procedure".
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or vis ual inspection) and intake door position is at fresh
when the DEF or D/F is selected. REC ( ) is not allowed in DEF ( ) D/F ( ) or FOOT ( ).
CHECKING TEMPERATURE DECREASE
1. Rotate temperature control dial (drive or passenger) counterclockwise until 18° C (60°F) is displayed.
2. Check for cold air at appropriate discharge air outlets. Conditions : Engine running and at normal operating temperature
Revision: March 2010
2008 QX56

INTAKE DOOR MOTORHAC-41
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
C
D
E
F
G H
J
K L
M A
B
HAC
N
O P
COMPONENT DESCRIPTION
Intake door motor
The intake door motor is attached to the intake unit. It rotates so that
air is drawn from inlets set by the A/C auto amp. Motor rotation is
conveyed to a lever which activates the intake door.
Intake Door Motor Component Function CheckINFOID:0000000001679790
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OPERATIONAL CHECK - REC ( )
1. Press the mode switch to vent mode( ).
2. Press REC ( ) switch. The REC ( )indicator should illuminate.
3. Press REC ( ) switch again. The REC ( ) indicator should go out.
4. Listen for intake door position change (you should hear blower sound change slightly).
Can a symptom be duplicated?
YES >> GO TO 3.
NO >> GO TO 2.
2.PERFORM COMPLETE OPERATIONAL CHECK
Perform a complete operational check and check for any symptoms. Refer to HAC-4, "
Operational Check
(Front)".
Can a symptom be duplicated?
YES >> Refer to HAC-3, "How to Perform Trouble Diagnosis For Quick And Accurate Repair".
NO >> System OK.
3.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 4.
4.CHECK INTAKE DOOR OPERATION
Check and verify intake door me chanism for smooth operation.
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair intake door mechanism.
5.PERFORM SELF-DIAGNOSIS
Perform self-diagnosis to check for any codes. Refer to HAC-22, "
A/C and AV Switch Assembly Self-Diagno-
sis".
Are any self-diagnosis codes present?
YES >> Refer to HAC-23, "A/C System Self-Diagnosis Code Chart".
NO >> GO TO 6.
6.RECHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to HAC-4, "
Operational Check (Front)".
Does another symptom exist?
YES >> Refer to HAC-3, "How to Perform Trouble Diagnosis For Quick And Accurate Repair".
NO >> Replace A/C auto amp. Refer to VTL-7, "
Removal and Installation".
WJIA0552E
Revision: March 2010 2008 QX56

DEFROSTER DOOR MOTOR CIRCUITHAC-45
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
C
D
E
F
G H
J
K L
M A
B
HAC
N
O P
Defroster Door Motor Co mponent Function CheckINFOID:0000000001679793
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING O PERATIONAL CHECK - DEFROSTER DOOR
1. Press the mode switch and select vent ( ).
2. Press the defrost switch ( ). Defroster indicator should illuminate (on display).
3. Listen for defroster door position change (blower sound should change slightly).
Can the symptom be duplicated?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK FOR ANY SYMPTOMS
Perform a complete operational check for any symptoms. Refer to HAC-4, "
Operational Check (Front)".
Does another symptom exist?
YES >> Refer to HAC-3, "How to Perform Trouble Diagnosis For Quick And Accurate Repair".
NO >> SYSTEM OK.
3.CHECK FOR SERVICE BULLETINS
Check for any service bulletins.
>> GO TO 4.
4.CHECK DEFROSTER DOOR MOTOR
Perform diagnostic procedure for defroster door motor. Refer to HAC-45, "
Defroster Door Motor Component
Function Check".
Is the inspection result normal?
YES >> GO TO 5.
NO >> Repair PBR circuit or replace defroster door motor. Refer to VTL-21, "
Removal and Installation".
5.CHECK DEFROSTER DOOR OPERATION
Check and verify defroster door mechanism for smooth operation.
Is the inspection result normal?
YES >> Replace defroster door motor. Refer to VTL-21, "Removal and Installation".
NO >> Repair defroster door mechanism.
Defroster Door Motor Diagnosis ProcedureINFOID:0000000001679794
SYMPTOM:
• Defroster door does not change.
• Defroster door motor does not operate normally.
DIAGNOSTIC PROCEDURE FOR DEFROSTER DOOR MOTOR
1.CHECK A/C AUTO AMP. FOR POWER AND GROUND
1. Turn ignition switch ON.
2. Press the defroster switch ( ).
3. Check voltage between A/C auto amp. harness connector M49 terminal 24 and terminal 23 and press the defroster switch ( )
again.
Connector Te r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
A/C auto amp.: M49 24 23 Press de-
froster switch Battery
voltage
AWIIA0152ZZ
Revision: March 2010 2008 QX56

HAC-84
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
OPTICAL SENSOR
OPTICAL SENSOR
Component DescriptionINFOID:0000000001679819
COMPONENT DESCRIPTION
The optical sensor (1) is located in
the center of the defroster grille. It
detects sunload entering through windshield by means of a photo
diode. The sensor converts the sunload into a current value which is
then input into the A/C auto amp.
OPTICAL INPUT PROCESS
The A/C auto amp. includes a processing circuit which averages the variations in detected sunload over a
period of time. This prevents adjustments in the ATC system operation due to small or quick variations in
detected sunload.
For example, consider driving along a road bordered by an occasional group of large trees. The sunload
detected by the optical sensor will va ry whenever the trees obstruct the sunlight. The processing circuit aver-
ages the detected sunload over a period of time, so that the (insignificant) effect of the trees momentarily
obstructing the sunlight does not cause any change in the ATC system operation. On the other hand, shortly
after entering a long tunnel, the system will recognize the change in sunload, and the system will react accord-
ingly.
Optical Sensor Diagnosis ProcedureINFOID:0000000001679820
DIAGNOSTIC PROCEDURE FOR OPTICAL SENSOR
SYMPTOM: Optical sensor circuit is open or shorted. Using the
CONSULT-III, DTC B257F or B2580 is displayed. Without a CON-
SULT-III, code 50 or 52 is indicated on A/C auto amp. as a result of
conducting self-diagnosis.
1.CHECK CIRCUIT CONTINUITY BETWEEN OPTICAL SENSOR AND A/C AUTO AMP.
1. Turn ignition switch OFF.
2. Disconnect A/C auto amp. connector and optical sensor connec- tor.
3. Check continuity between optical sensor harness connector M302 (B) terminals 1 and 2 and A/C auto amp. harness connec-
tor M50 (C) terminal 42 and M49 (A) terminal 1.
4. Check continuity between optical sensor harness connector M302 (B) terminal 1 and 2 and ground.
AWIIA0169ZZ
AWIIA0205GB
1 - 1 : Continuity should exist.
2 - 42 : Continuity should exist.
AWIIA0206ZZ
Revision: March 2010 2008 QX56

INSUFFICIENT COOLINGHAC-115
< SYMPTOM DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
C
D
E
F
G H
J
K L
M A
B
HAC
N
O P
Both High- and Low-pressure Sides are Too Low
Low-pressure Side Some
times Becomes Negative
Gauge indication Refrigerant cycleProbable causeCorrective action
High-pressure side is too low and
low-pressure side is too high. High- and low-pressure sides
become equal soon after com-
pressor operation stops.Compressor pressure opera-
tion is improper.
↓
Damaged inside compressor
packings.
Replace compressor.
No temperature difference be-
tween high- and low-pressure
sides. Compressor pressure opera-
tion is improper.
↓
Damaged inside compressor
packings.
Replace compressor.
AC356A
Gauge indication
Refrigerant cycleProbable causeCorrective action
Both high- and low-pressure sides
are too low. • There is a big temperature
difference between liquid
tank outlet and inlet. Outlet
temperature is extremely
low.
• Liquid tank inlet and expan- sion valve are frosted. Liquid tank inside is slightly
clogged.
• Replace liquid tank.
• Check oil for contamination.
• Temperature of expansion valve inlet is extremely low
as compared with areas
near liquid tank.
• Expansion valve inlet may be frosted.
• Temperature difference oc-
curs somewhere in high-
pressure side. High-pressure pipe located be-
tween liquid tank and expan-
sion valve is clogged.
• Check and repair malfunc-
tioning parts.
• Check oil for contamination.
Expansion valve and liquid
tank are warm or only cool
when touched. Low refrigerant charge.
↓
Leaking fittings or compo-
nents.Check refrigerant system for
leaks. Refer to HA-24, "
Check-
ing of Refrigerant Leaks".
There is a big temperature dif-
ference between expansion
valve inlet and outlet while the
valve itself is frosted. Expansion valve closes a little
compared with the specifica-
tion.
↓
1. Improper expansion
valve adjustment.
2. Malfunctioning expansion valve.
3. Outlet and inlet may be clogged. • Remove foreign particles by
using compressed air.
• Check oil for contamination.
An area of the low-pressure
pipe is colder than areas near
the evaporator outlet. Low-pressure pipe is clogged
or crushed.• Check and repair malfunc-
tioning parts.
• Check oil for contamination.
Air flow volume is too low. Evaporator is frozen. • Check intake sensor circuit.
Refer to HAC-86, "
Intake
Sensor Diagnosis Proce-
dure".
• Repair evaporator fins.
• Replace evaporator.
• Refer to HAC-50, "
Front
Blower Motor Component
Function Check".
AC353A
Revision: March 2010 2008 QX56

INL-1
DRIVER CONTROLS
C
DE
F
G H
I
J
K
M
SECTION INL
A
B
INL
N
O P
CONTENTS
INTERIOR LIGHTING SYSTEM
BASIC INSPECTION ....... .............................3
DIAGNOSIS AND REPAIR WORKFLOW ..... .....3
Work Flow ........................................................... ......3
FUNCTION DIAGNOSIS ...............................6
INTERIOR ROOM LAMP CONTROL SYSTEM
.....
6
System Diagram .................................................. ......6
System Description ...................................................6
Component Parts Location ........................................7
Component Description .............................................8
ILLUMINATION CONTROL SYSTEM .................9
System Diagram .................................................. ......9
System Description ...................................................9
Component Parts Location ........................................9
Component Description ...........................................10
DIAGNOSIS SYSTEM (BCM) ............................11
COMMON ITEM ..................................................... ....11
COMMON ITEM : CONSULT-III Function ...............11
INT LAMP .............................................................. ....11
INT LAMP : CONSULT-III Function ........................11
BATTERY SAVER ................................................. ....13
BATTERY SAVER : CONSULT-III Function ...........13
COMPONENT DIAGNOSIS .........................14
POWER SUPPLY AND GROUND CIRCUIT .. ....14
BCM ....................................................................... ....14
BCM : Inspection Procedure ...................................14
INTERIOR ROOM LAMP POWER SUPPLY
CIRCUIT ......................................................... ....
15
Description .......................................................... ....15
Component Function Check ....................................15
Diagnosis Procedure ...............................................15
INTERIOR ROOM LAMP CONTROL CIRCUIT
...
17
Description ........................................................... ....17
Component Function Check ....................................17
Diagnosis Procedure ...............................................17
STEP LAMP CIRCUIT .......................................19
Description ........................................................... ....19
Component Function Check ....................................19
Diagnosis Procedure ...............................................19
CARGO LAMP CONTROL CIRCUIT ................21
Description ...............................................................21
Component Function Check ....................................21
Diagnosis Procedure ...............................................21
IGNITION KEYHOLE ILLUMINATION CON-
TROL CIRCUIT .................................................
23
Description ...............................................................23
Component Function Check ....................................23
Diagnosis Procedure ...............................................23
INTERIOR ROOM LAMP CONTROL SYSTEM
...
25
Wiring Diagram .................................................... ....25
ILLUMINATION .................................................41
Wiring Diagram ........................................................41
ECU DIAGNOSIS .........................................55
BCM (BODY CONTROL MODULE) .................55
Description ........................................................... ....55
SYMPTOM DIAGNOSIS ..............................56
INTERIOR LIGHTING SYSTEM SYMPTOMS ...56
Symptom Table ................................................... ....56
PRECAUTION ..............................................57
PRECAUTIONS .................................................57
Revision: March 2010 2008 QX56

ILLUMINATION CONTROL SYSTEMINL-9
< FUNCTION DIAGNOSIS >
C
DE
F
G H
I
J
K
M A
B
INL
N
O P
ILLUMINATION CONTROL SYSTEM
System DiagramINFOID:0000000001601379
System DescriptionINFOID:0000000001601380
The illumination lamps operation is dependent upon the posit ion of the lighting switch (combination switch).
When the lighting switch is placed in the 1ST or 2ND posit ion (or if the auto light system is activated) the BCM
(body control module) receives input requesting the park ing lamps to illuminate. This input is communicated to
the IPDM E/R (intelligent power distribution module engine room) via the CAN communication lines. The CPU
(central processing unit) of the IPDM E/R controls the tail lamp relay coil. When energized, this relay directs
power to the parking and illumination lamps, which then illuminate.
BATTERY SAVER CONTROL
When the lighting switch (combination switch) is in t he 1ST or 2ND position and the ignition switch is turned
from ON or ACC to OFF, the battery saver control feat ure is activated. Under this condition, the illumination
lamps remain illuminated for 30 minutes unless the light ing switch position is changed. If the lighting switch
position is changed, then the illumination lamps are turned off after a 30 second delay. When the lighting
switch is turned from OFF to 1ST or 2ND position (or if auto light system is activated) after illumination lamps
have been turned off by the battery saver control, the illumination lamps illuminate again.
Component Parts LocationINFOID:0000000001601381
ALLIA0424GB
1. BCM M18, M20 (view with instrument
lower panel LH removed) 2. IPDM E/R E122, E123, E124 3. Combination switch M28
4. Combination meter (illumination con- trol switch) M23, M24
AWLIA0398ZZ
Revision: March 2010 2008 QX56

INL-10
< FUNCTION DIAGNOSIS >
ILLUMINATION CONTROL SYSTEM
Component Description
INFOID:0000000001601382
Part name Description
BCM The BCM monitors the lighting switch position with the combina-
tion switch reading function. The BCM requests, via CAN com-
munication, that the IPDM E/R activate the tail lamp relay.
IPDM E/R The IPDM E/R activates the tail lamp relay based on inputs re-
ceived from the BCM via the CAN communication network.
Combination meter (illumination control switch) The illumination control switch is a part of the combination meter.
The combination meter controls illumination intensity by varying
ground to the illumination lamps based on the illumination control
switch position.
Combination switch The combination switch provides input to the BCM about the light-
ing switch position.
Revision: March 2010
2008 QX56