2010 INFINITI QX56 change time

EXT-8
< SERVICE INFORMATION >
SQUEAK AND RATTLE TROUBLE DIAGNOSES
Most of these incidents can be repaired by adjusting, securing or insulating the item(s) or component(s) caus-
ing the noise.
SUNROOF/HEADLINING
Noises in the sunroof/headlining area c an often be traced to one of the following:
1. Sunroof lid, rail, linkage or seals making a rattle or light knocking noise
2. Sun visor shaft shaking in the holder
3. Front or rear windshield touching headliner and squeaking
Again, pressing on the components to stop the noise while duplicating the conditions can isolate most of these
incidents. Repairs usually consist of insulating with felt cloth tape.
OVERHEAD CONSOLE (FRONT AND REAR)
Overhead console noises are often caused by the c onsole panel clips not being engaged correctly. Most of
these incidents are repaired by pushing up on the c onsole at the clip locations until the clips engage.
In addition look for:
1. Loose harness or harness connectors.
2. Front console map/reading lamp lens loose.
3. Loose screws at console attachment points.
SEATS
When isolating seat noise it's important to note the pos ition the seat is in and the load placed on the seat when
the noise is present. These conditions should be duplicated when verifying and isolating the cause of the
noise.
Cause of seat noise include:
1. Headrest rods and holder
2. A squeak between the seat pad cushion and frame
3. The rear seatback lock and bracket
These noises can be isolated by moving or pressing on the suspected components while duplicating the con-
ditions under which the noise occurs. Most of thes e incidents can be repaired by repositioning the component
or applying urethane tape to the contact area.
UNDERHOOD
Some interior noise may be caused by components under the hood or on the engine wall. The noise is then
transmitted into the passenger compartment.
Causes of transmitted underhood noise include:
1. Any component installed to the engine wall
2. Components that pass through the engine wall
3. Engine wall mounts and connectors
4. Loose radiator installation pins
5. Hood bumpers out of adjustment
6. Hood striker out of adjustment
These noises can be difficult to isolate since they cannot be reached from the interior of the vehicle. The best
method is to secure, move or insulate one component at a time and test drive the \
vehicle. Also, engine RPM
or load can be changed to isolate the noise. Repairs can usually be made by moving, adjusting, securing, or
insulating the component causing the noise.
Revision: April 20092010 QX56

SERVICE INFORMATION FOR ELECTRICAL INCIDENTGI-41
< BASIC INSPECTION >
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Circuit InspectionINFOID:0000000005149608
DESCRIPTION
• In general, testing electrical circuits is an easy task if it is approached in a logical and organized method. Before beginning it is important to have all available information on the system to be tested. Also, get a thor-
ough understanding of system operation. Then you will be able to use the appropriate equipment and follow
the correct test procedure.
• You may have to simulate vehicle vibrations while te sting electrical components. Gently shake the wiring
harness or electrical component to do this.
NOTE:
Refer to GI-35, "
How to Check Terminal" to probe or check terminal.
TESTING FOR “OPENS” IN THE CIRCUIT
Before you begin to diagnose and test the system, you should rough sketch a schematic of the system. This
will help you to logically walk through the diagnosis process. Drawing the sketch will also reinforce your work-
ing knowledge of the system.
Continuity Check Method
The continuity check is used to find an open in the circui t. The digital multimeter (DMM) set on the resistance
function will indicate an open circuit as over limit (no beep tone or no ohms symbol). Make sure to always start
with the DMM at the highest resistance level.
To help in understanding the diagnosis of open circui ts, please refer to the previous schematic.
• Disconnect the battery negative cable.
• Start at one end of the circuit and work your way to the other end. (At the fuse block in this example)
• Connect one probe of the DMM to the fuse block terminal on the load side.
• Connect the other probe to the fuse block (power) side of SW1. Little or no resistance will indicate that por-
tion of the circuit has good continuity. If there were an open in the circuit, the DMM would indicate an over
limit or infinite resistance condition. (point A)
• Connect the probes between SW1 and the relay. Little or no resistance will indicate that portion of the circuit
has good continuity. If there were an open in the circuit, t he DMM would indicate an over limit or infinite resis-
tance condition. (point B)
• Connect the probes between the relay and the solenoid. Little or no resistance will indicate that portion of the
circuit has good continuity. If there were an open in the ci rcuit, the DMM would indicate an over limit or infi-
nite resistance condition. (point C)
Any circuit can be diagnosed using the approach in the previous example.
Voltage Check Method
To help in understanding the diagnosis of open circuits please refer to the previous schematic.
In any powered circuit, an open can be found by methodica lly checking the system for the presence of voltage.
This is done by switching the DMM to the voltage function.
• Connect one probe of the DMM to a known good ground.
• Begin probing at one end of the circuit and work your way to the other end.
• With SW1 open, probe at SW1 to check for voltage. voltage; open is further down the circuit than SW1.
OPEN A circuit is open when there is no continuity through a section of the circuit.
SHORT There are two types of shorts.
• SHORT CIRCUIT
When a circuit contacts another circuit and causes the normal resistance to
change.
• SHORT TO GROUND When a circuit contacts a ground source and grounds the circuit.
SGI846-A
Revision: April 20092010 QX56

SQUEAK AND RATTLE TROUBLE DIAGNOSISGW-5
< SYMPTOM DIAGNOSIS >
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2. Trunk lid striker out of adjustment
3. The trunk lid torsion bars knocking together
4. A loose license plate or bracket
Most of these incidents can be repaired by adjusting, se curing or insulating the item(s) or component(s) caus-
ing the noise.
SUNROOF/HEADLINING
Noises in the sunroof/headlining area can often be traced to one of the following:
1. Sunroof lid, rail, linkage or seals making a rattle or light knocking noise
2. Sun visor shaft shaking in the holder
3. Front or rear windshield touching headliner and squeaking
Again, pressing on the components to stop the noise while duplicating the conditions can isolate most of these
incidents. Repairs usually consist of insulating with felt cloth tape.
OVERHEAD CONSOLE (FRONT AND REAR)
Overhead console noises are often caused by the cons ole panel clips not being engaged correctly. Most of
these incidents are repaired by pushing up on the c onsole at the clip locations until the clips engage.
In addition look for:
1. Loose harness or harness connectors.
2. Front console map/reading lamp lense loose.
3. Loose screws at console attachment points.
SEATS
When isolating seat noise it's important to note the position the seat is in and the load placed on the seat when
the noise is present. These conditions should be duplicated when verifying and isolating the cause of the
noise.
Cause of seat noise include:
1. Headrest rods and holder
2. A squeak between the seat pad cushion and frame
3. The rear seatback lock and bracket
These noises can be isolated by moving or pressing on the suspected components while duplicating the con-
ditions under which the noise occurs. Most of thes e incidents can be repaired by repositioning the component
or applying urethane tape to the contact area.
UNDERHOOD
Some interior noise may be caused by components under the hood or on the engine wall. The noise is then
transmitted into the passenger compartment.
Causes of transmitted underhood noise include:
1. Any component mounted to the engine wall
2. Components that pass through the engine wall
3. Engine wall mounts and connectors
4. Loose radiator mounting pins
5. Hood bumpers out of adjustment
6. Hood striker out of adjustment
These noises can be difficult to isolate since they cannot be reached from the interior of the vehicle. The best
method is to secure, move or insulate one component at a time and test drive the vehicle. Also, engine RPM
or load can be changed to isolate the noise. Repairs can usually be made by moving, adjusting, securing, or
insulating the component causing the noise.
Revision: April 20092010 QX56

HAC-4
< BASIC INSPECTION >[AUTOMATIC AIR CONDITIONER]
INSPECTION AND ADJUSTMENT
INSPECTION AND ADJUSTMENT
Operational Check (Front)INFOID:0000000005147669
The purpose of the operational check is to
confirm that the system operates properly.
CHECKING MEMORY FUNCTION
1. Set the temperature to 32 ° (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-120, "
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-48, "
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-16, "
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-40, "
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: April 20092010 QX56

DIAGNOSIS SYSTEM (BCM)HAC-21
< FUNCTION DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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DIAGNOSIS SYSTEM (BCM)
CONSULT-III Function (BCM - COMMON ITEM)INFOID:0000000005273928
APPLICATION ITEM
CONSULT-III performs the following functions via CAN communication with BCM.
SYSTEM APPLICATION
BCM can perform the following functions for each system.
NOTE:
It can perform the diagnosis modes except the following for all sub system selection items.
CONSULT-III Function (BCM - AIR CONDITIONER)INFOID:0000000005273929
DATA MONITOR
Diagnosis mode Function Description
WORK SUPPORT Changes the setting for each system function.
SELF-DIAG RESULTS Displays the diagnosis results judged by BCM. Refer to BCS-54, "
DTCIndex".
CAN DIAG SUPPORT MNTR Monitors the reception status of CAN communication viewed from BCM.
DATA MONITOR The BCM input/output signals are displayed.
ACTIVE TEST The signals used to activate each device are forcibly supplied from BCM.
ECU IDENTIFICATION The BCM pa rt number is displayed.
CONFIGURATION • Enables to read and save the vehicle specification.
• Enables to write the vehicle specification when replacing BCM.
System
Sub system selection item Diagnosis mode
WORK SUPPORT DATA MONITOR ACTIVE TEST
BCM BCM ×
Door lock DOOR LOCK ×××
Rear window defogger REAR DEFOGGER ×
Warning chime BUZZER ××
Interior room lamp timer INT LAMP ×××
Exterior lamp HEAD LAMP ×××
Wiper and washer WIPER ×××
Turn signal and hazard warning lamps FLASHER ××
Air conditioner AIR CONDITONER ×
Intelligent Key system INTELLIGENT KEY ×
Combination switch COMB SW ×
Immobilizer IMMU ××
Interior room lamp battery saver BATTERY SAVER ×××
Back door open TRUNK ××
RAP (retained accessory power) RETAINED PWR ×××
Signal buffer system SIGNAL BUFFER ××
TPMS (tire pressure monitoring sys-
tem) AIR PRESSURE MONITOR
×××
Panic alarm system PANIC ALARM ×
Revision: April 20092010 QX56

HAC-26
< COMPONENT DIAGNOSIS >[AUTOMATIC AIR CONDITIONER]
MODE DOOR MOTOR
The mode door motor (front) is attached to the heater & cooling unit
assembly. It rotates so that air is discharged from the outlet as indi-
cated by the A/C auto amp. Motor rotation is conveyed to a link
which activates the mode door.
Mode Door Motor (Front)
Component Function CheckINFOID:0000000005147688
INSPECTION FLOW
1.CONFIRM SYMPTOM BY PERFORMING OP ERATIONAL CHECK - DISCHARGE AIR
1. Press mode switch four times and then press the (DEF) switch. Each position indicator should change shape (on display).
2. Confirm that discharge air comes out according to the air distribution table. Refer to HAC-16, "
Discharge
Air Flow (Front)".
NOTE:
Confirm that the compressor clutch is engaged (visual inspection) and intake door position is at FRESH
when DEF ( ) or D/F ( ) is selected.
Is the inspection result normal?
YES >> Inspection End.
NO >> Go to diagnosis procedure. Refer to HAC-26, "
Mode Door Motor (Front) Diagnosis Procedure".
Mode Door Motor (Front) Diagnosis ProcedureINFOID:0000000005147689
Regarding Wiring Diagram information, refer to HAC-91, "Wiring Diagram".
SYMPTOM:• Air outlet does not change.
• Mode door motor does not operate normally.
1.CHECK A/C AUTO AMP. FOR POWER AND GROUND
1. Turn ignition switch ON.
2. Press the mode switch to the B/L ( ) mode.
3. Check voltage between A/C auto amp. harness connector M49 terminal 19 and terminal 20 while pressing the mode switch to
the floor ( ) mode.
Is the inspection result normal?
YES >> GO TO 3.
NO >> GO TO 2.
2.CHECK MODE DOOR MOTOR CIRCUITS FOR SHORT TO GROUND
WJIA0587E
Connector Te r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
A/C auto amp.: M49 20
19Press
mode
switch Battery
voltage
AWIIA0095ZZ
Revision: April 20092010 QX56

OPTICAL SENSORHAC-81
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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OPTICAL SENSOR
Component DescriptionINFOID:0000000005147724
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 vary whenever the tr ees 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 t he 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:0000000005147725
Regarding Wiring Diagram information, refer to HAC-91, "Wiring Diagram".
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 OP TICAL SENSOR AND A/C AUTO AMP.
AWIIA0169ZZ
AWIIA1067GB
Revision: April 20092010 QX56

INSUFFICIENT COOLINGHAC-113
< SYMPTOM DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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dard (usual) pressure, however, differs from vehicle to vehicle, refer to above table (Ambient air temperature-
to-operating pressure table).
Both High- and Low-pressure Sides are Too High
High-pressure Side is Too High and Low-pressure Side is Too Low
High-pressure Side is Too Low and Low-pressure Side is Too High
Gauge indication Refrigerant cycleProbable causeCorrective action
Both high- and low-pressure sides
are too high. Pressure is reduced soon af-
ter water is splashed on con-
denser.
Excessive refrigerant charge in
refrigeration cycle
Reduce refrigerant until speci-
fied pressure is obtained.
Air suction by cooling fan is in-
sufficient. Insufficient condenser cooling
performance
↓
1. Condenser fins are
clogged.
2. Improper fan rotation of
cooling fan • Clean condenser.
• Check and repair cooling fan
if necessary.
• Low-pressure pipe is not cold.
• When compressor is
stopped high-pressure val-
ue quickly drops by approx-
imately 196 kPa (2 kg/cm
2 ,
28 psi). It then decreases
gradually thereafter. Poor heat exchange in con-
denser
(After compressor operation
stops, high-pressure decreas-
es too slowly.)
↓
Air in refrigeration cycle
Evacuate and recharge system.
Engine tends to overheat. Engine cooling systems mal-
function. Check and repair engine cool-
ing system.
• An area of the low-pressure pipe is colder than areas
near the evaporator outlet.
• Plates are sometimes cov- ered with frost. • Excessive liquid refrigerant
on low-pressure side
• Excessive refrigerant dis-
charge flow
• Expansion valve is open a lit- tle compared with the speci-
fication.
↓
Improper expansion valve ad-
justment Replace expansion valve.
AC359A
Gauge indication
Refrigerant cycleProbable causeCorrective action
High-pressure side is too high and
low-pressure side is too low. Upper side of condenser and
high-pressure side are hot,
however, liquid tank is not so
hot.High-pressure tube or parts lo-
cated between compressor
and condenser are clogged or
crushed.
• Check and repair or replace
malfunctioning parts.
• Check oil for contamination.
AC360A
Revision: April 20092010 QX56