Infiniti QX56 (Z62). Manual - part 811

REAR AUTOMATIC AIR CONDITIONING SYSTEM

HAC-135

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONING]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

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P

REAR AUTOMATIC AIR CONDITIONING SYSTEM

Diagnosis Chart By Symptom

INFOID:0000000006275981

NOTE:
• Perform the self-diagnoses with CONSULT-III before performing the symptom diagnosis. If DTC is detected,

perform the corresponding diagnosis.

• The following table is based on the condition that front automatic air conditioning system operates normally.

Symptom

Corresponding malfunction part

Reference

• Rear air conditioning system cannot be controlled.

(Front A/C control)

• Operation status of rear air conditioning system is 

not indicated on front display.

Multi AV system

AV-199, "Symptom Table"

Rear air conditioning sys-
tem cannot be controlled. 
(Rear A/C control)

Operation status of 
rear air conditioning 
system is not indicated 
on rear A/C control 
display

• Power supply system of rear A/C 

control

• Rear A/C control

HAC-115, "REAR A/C CONTROL : 
Diagnosis Procedure"

Operation status of 
rear air conditioning 
system is indicated on 
rear A/C control dis-
play

• Communication circuit between rear 

A/C control and A/C auto amp.

• A/C auto amp.

HAC-127, "Diagnosis Procedure"

• Air outlet does not change.
• Rear mode door motor does not operate normally.

• Circuit between rear mode door mo-

tor and A/C auto amp. 

• Rear mode door motor control link-

age

• Front mode door motor
• A/C auto amp.

HAC-116, "REAR MODE DOOR 
MOTOR : Diagnosis Procedure"

• Discharge air temperature does not change.
• Rear air mix door motor does not operate normally.

• Circuit between rear air mix door 

motor and A/C auto amp. 

• Rear air mix door motor installation 

condition

• Rear air mix door motor
• A/C auto amp.

HAC-114, "REAR AIR MIX DOOR 
MOTOR : Diagnosis Procedure"

Rear blower motor operation is malfunctioning.

• Power supply system of rear blower 

motor

• Circuit between rear blower motor 

and A/C auto amp..

• Rear blower motor
• A/C auto amp.

HAC-131, "Diagnosis Procedure"

• Insufficient cooling.
• No cool air comes out. (Air flow volume is normal.)

• Power supply system of rear A/C re-

lay

• Circuit between rear A/C relay and 

A/C auto amp..

• Circuit between rear A/C relay and 

rear A/C solenoid valve.

• Circuit between rear A/C solenoid 

valve and ground.

• Rear A/C relay
• Rear A/C solenoid valve
• A/C auto amp.
• Refrigerant cycle
• Air leakage from each duct
• Temperature setting trimmer (rear)

HAC-139, "REAR AIR CONDI-
TIONER : Diagnosis Procedure"

HAC-136

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONING]

REAR AUTOMATIC AIR CONDITIONING SYSTEM

• Insufficient heating.
• No warm air comes out. (Air flow volume is nor-

mal.)

• Engine cooling system
• Heater hose
• Rear heater core
• Air leakage from each duct
• Temperature setting trimmer (rear)

HAC-141, "REAR AIR CONDI-
TIONER : Diagnosis Procedure"

Noise is heard when rear blower motor operates.

• Mixing any foreign object in rear 

blower motor

• Rear blower motor fan breakage
• Rear blower motor rotation inferiori-

ty

HAC-132, "Component Inspection"

Symptom

Corresponding malfunction part

Reference

ACCS (ADVANCE CLIMATE CONTROL SYSTEM)

HAC-137

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONING]

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D

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ACCS (ADVANCE CLIMATE CONTROL SYSTEM)

Symptom Table

INFOID:0000000006275982

NOTE:
• Perform the self-diagnoses with CONSULT-III before performing the symptom diagnosis. If DTC is detected,

perform the corresponding diagnosis.

• The following table is based on the condition that front automatic air conditioning system operates normally.

Symptom

Corresponding malfunction part

Reference

Auto intake switch cannot be operated. [Automatic 
intake control (exhaust gas / outside odor detecting 
mechanism) does not operate]

Multi AV system

AV-199, "Symptom Table"

Plasmacluster

™

 control does not operate.

NOTE:

• Plasmacluster

™

 ion technology developed by 

Sharp Corporation is installed in this item.

• Plasmacluster

™

 is a trademark of Sharp Corpora-

tion.

• Power supply system of ionizer
• The circuit between ionizer and A/C 

auto amp.

• Ionizer
• A/C auto amp.

HAC-124, "Diagnosis Procedure"

Operation status of Plasmacluster

™

 control does not 

switch according to air flow.
NOTE:

• Plasmacluster

™

 ion technology developed by 

Sharp Corporation is installed in this item.

• Plasmacluster

™

 is a trademark of Sharp Corpora-

tion.

A/C auto amp.

Replace A/C auto amp.. Refer to 

HAC-146, "Removal and Installa-
tion"

.

HAC-138

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONING]

INSUFFICIENT COOLING

INSUFFICIENT COOLING

FRONT AIR CONDITIONER

FRONT AIR CONDITIONER : Description

INFOID:0000000006275984

Symptom

• Insufficient cooling
• No cool air comes out. (Air flow volume is normal.)

FRONT AIR CONDITIONER : Diagnosis Procedure

INFOID:0000000006275985

NOTE:
Perform self-diagnoses with CONSULT-III before performing symptom diagnosis. If any DTC is detected, per-
form the corresponding diagnosis.

1.

CHECK MAGNET CLUTCH OPERATION

1.

Turn ignition switch ON.

2.

Operate fan switch.

3.

Press A/C switch.

4.

Check that A/C indicator turns ON. Check visually and by sound that compressor operates.

5.

Press A/C switch again.

6.

Check that A/C indicator turns OFF. Check that compressor stops.

Is the inspection result normal?

YES

>> GO TO 2.

NO

>> Perform diagnosis of “COMPRESSOR DOSE NOT OPERATE” in “SYMPTOM DIAGNOSIS”.

Refer to 

HAC-142, "Diagnosis Procedure"

.

2.

CHECK DRIVE BELT

Check tension of drive belt. Refer to 

EM-20, "Checking"

.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Adjust or replace drive belt depending on the inspection results.

3.

CHECK REFRIGERANT CYCLE

Connect recovery/recycling recharging equipment to the vehicle and perform pressure inspection with gauge.
Refer to 

HA-27, "Symptom Table"

.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace parts depending on the inspection results.

4.

CHECK AIR LEAKAGE FROM EACH DUCT

Check duct and nozzle, etc. of the front air conditioning system for leakage.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Repair or replace parts depending on the inspection results.

5.

CHECK AMBIENT TEMPERATURE DISPLAY

Check that there is not much diference between actual ambient temperature and indicated temperature on
information display in combination meter.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Perform diagnosis for the A/C auto amp. connection recognition signal circuit. Refer to 

MWI-74,

"Diagnosis Procedure"

.

6.

CHECK SETTING OF TEMPERATURE SETTING TRIMMER (FRONT)

1.

Check setting value of temperature setting trimmer (front). Refer to 

HAC-68, "FRONT AUTOMATIC AIR

CONDITIONING SYSTEM : Temperature Setting Trimmer (Front)"

. 

2.

Check that temperature setting trimmer (front) is set to “+ direction”.