Infiniti G37 Coupe. Manual - part 785

AIR CONDITIONER CONTROL

HAC-129

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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SYMPTOM DIAGNOSIS

AIR CONDITIONER CONTROL

Diagnosis Chart By Symptom

INFOID:0000000001675740

Symptom

Reference

A/C system does not activate.

Go to Trouble Diagnosis Procedure for A/C System.

HAC-101, "Diagnosis Procedure"

A/C system cannot be controlled.

Go to Preset Switch System.

AV-103, "Symptom Table"

 (BASE 

AUDIO WITHOUT NAVIGATION), 

AV-335, "Symptom Table"

 (BOSE 

AUDIO WITHOUT NAVIGATION) 

or 

AV-596, "Symptom Table"

 

(BOSE AUDIO WITH NAVIGA-

TION)

Air outlet does not change.

Go to Trouble Diagnosis Procedure for Mode Door Motor. 
(LAN)

HAC-67, "Diagnosis Procedure"

Mode door motor does not operate 
normally.

Discharge air temperature does not 
change.

Go to Trouble Diagnosis Procedure for Air Mix Door Motor. 
(LAN)

HAC-70, "WITHOUT LEFT AND 

RIGHT VENTILATION TEMPER-

ATURE SEPARATELY CONTROL 

SYSTEM : Diagnosis Procedure"

 

(Without left and right ventilation 

temperature separately control 

system) or 

HAC-72, "WITH LEFT 

AND RIGHT VENTILATION TEM-

PERATURE SEPARATELY CON-

TROL SYSTEM : Diagnosis 

Procedure"

 (With left and right 

ventilation temperature separately 

control system)

Air mix door motor does not operate 
normally.

Intake door does not change.

Go to Trouble Diagnosis Procedure for Intake Door Motor. 
(LAN)

HAC-75, "Diagnosis Procedure"

Intake door motor does not operate 
normally.

Blower motor operation is malfunc-
tioning.

Go to Trouble Diagnosis Procedure for Blower Motor.

HAC-77, "WITHOUT LEFT AND 

RIGHT VENTILATION TEMPER-

ATURE SEPARATELY CONTROL 

SYSTEM : Diagnosis Procedure"

 

(Without left and right ventilation 

temperature separately control 

system) or 

HAC-81, "WITH LEFT 

AND RIGHT VENTILATION TEM-

PERATURE SEPARATELY CON-

TROL SYSTEM : Diagnosis 

Procedure"

 (With left and right 

ventilation temperature separately 

control system)

Magnet clutch does not engage.

Go to Trouble Diagnosis Procedure for Magnet Clutch.

HAC-85, "Diagnosis Procedure"

Insufficient cooling

Go to Trouble Diagnosis Procedure for Insufficient Cooling.

HAC-130, "Inspection procedure"

Insufficient heating

Go to Trouble Diagnosis Procedure for Insufficient Heating.

HAC-133, "Inspection procedure"

Noise

Go to Trouble Diagnosis Procedure for Noise.

HAC-135, "Inspection procedure"

Self-diagnosis cannot be per-
formed.

Go to Trouble Diagnosis Procedure for Self-diagnosis.

HAC-137, "Inspection procedure"

Memory function does not operate.

Go to Trouble Diagnosis Procedure for Memory Function.

HAC-138, "Inspection procedure"

HAC-130

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

INSUFFICIENT COOLING

INSUFFICIENT COOLING

Description

INFOID:0000000001675741

Symptom

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

Inspection procedure

INFOID:0000000001675742

1.

CHECK WITH A GAUGE OF REFRIGERANT RECONERY/RECYCLING RECHARGING EQUIPMENT

Connect refrigerant recovery/recycling recharging equipment to the vehicle and perform the pressure inspec-
tion with the gauge.

Is there refrigerant?

YES

>> GO TO 2.

NO-1

>> Check for refrigerant leakages with the refrigerant leakage detecting fluorescent leak detector.

Refer to 

HA-31, "Inspection"

.

NO-2

>> GO TO 2 after repairing or replacing the parts according to the inspection results.

2.

CHECK CHARGED REFRIGERANT AMOUNT

1.

Connect refrigerant recovery/recycling recharging equipment to the vehicle and discharge the refrigerant.

2.

Recharge with the proper amount of refrigerant and perform the inspection with the refrigerant leakage
detecting fluorescent leak detector. Refer to 

HA-31, "Inspection"

.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Refill the refrigerant and repair or replace the parts according to the inspection results.

3.

CHECK REFRIGERANT CYCLE PRESSURE

Connect refrigerant recovery/recycling recharging equipment to the vehicle and perform the performance test.
Refer to 

HA-29, "Performance Chart"

.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Perform the diagnosis with the gauge pressure. Refer to 

HA-7, "Trouble Diagnosis For Unusual

Pressure"

.

4.

CHECK SETTING OF TEMPERATURE SETTING TRIMMER

Check the setting of temperature setting trimmer. Refer to 

HAC-7, "WITHOUT LEFT AND RIGHT VENTILA-

TION TEMPERATURE SEPARATELY CONTROL SYSTEM : Temperature Setting Trimmer"

 (Without left and

right ventilation temperature separately control system) or 

HAC-11, "WITH LEFT AND RIGHT VENTILATION

TEMPERATURE SEPARATELY CONTROL SYSTEM : Temperature Setting Trimmer"

 (With left and right ven-

tilation temperature separately control system).
1.

Check that the temperature setting trimmer is set to “+ direction”. 
NOTE:
The control temperature can be set with the setting of temperature setting trimmer.

2.

Set temperature control dial to “0”.

Are the symptoms solved?

YES

>> Perform the setting separately if necessary. END.

NO

>> GO TO 5.

5.

PERFORM SELF-DIAGNOSIS STEP-2

Perform self-diagnosis STEP-2. Refer to 

HAC-42, "WITHOUT LEFT AND RIGHT VENTILATION TEMPERA-

TURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (Without left and right ventilation tempera-

ture separately control system) or 

HAC-48, "WITH LEFT AND RIGHT VENTILATION TEMPERATURE

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (With left and right ventilation temperature sepa-

rately control system), see Nos. 1 to 2.

Does code No. 20 appear on the display?

YES

>> GO TO 6.

INSUFFICIENT COOLING

HAC-131

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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NO

>> Go to appropriate malfunctioning sensor circuit. Refer to 

HAC-42, "WITHOUT LEFT AND RIGHT

VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

(Without left and right ventilation temperature separately control system) or 

HAC-48, "WITH LEFT

AND RIGHT VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Diagnosis
Description"

 (With left and right ventilation temperature separately control system), see No. 11.

6.

PERFORM SELF-DIAGNOSIS STEP-4

Perform self-diagnosis STEP-4. Refer to 

HAC-42, "WITHOUT LEFT AND RIGHT VENTILATION TEMPERA-

TURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (Without left and right ventilation tempera-

ture separately control system) or 

HAC-48, "WITH LEFT AND RIGHT VENTILATION TEMPERATURE

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (With left and right ventilation temperature sepa-

rately control system), see Nos.1 to 5.
Is it operated normally?

YES

>> GO TO 7.

NO

>> Perform the diagnosis applicable to each output device. 

7.

PERFORM SELF-DIAGNOSIS STEP-5

Perform self-diagnosis STEP-5. Refer to 

HAC-42, "WITHOUT LEFT AND RIGHT VENTILATION TEMPERA-

TURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (Without left and right ventilation tempera-

ture separately control system) or 

HAC-48, "WITH LEFT AND RIGHT VENTILATION TEMPERATURE

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (With left and right ventilation temperature sepa-

rately control system), see Nos.1 to 10.
Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Go to appropriate malfunctioning sensor circuit. Refer to 

HAC-42, "WITHOUT LEFT AND RIGHT

VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

(Without left and right ventilation temperature separately control system) or 

HAC-48, "WITH LEFT

AND RIGHT VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Diagnosis
Description"

 (With left and right ventilation temperature separately control system).

8.

CHECK DRIVE BELT

Check the drive belt. Refer to 

EM-12, "Checking"

.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Adjust or replace the drive belt.

9.

CHECK AIR LEAKAGE FROM DUCT

Check duct and nozzle, etc. of A/C system for air leakage.

Is the inspection result normal?

YES

>> GO TO 10.

NO

>> Repair or replace parts according to the inspection results.

10.

CHECK POWER SUPPLY FOR ECV (ELECTRIC CONTROL VALVE)

1.

Disconnect compressor (ECV) connector.

2.

Turn ignition switch ON.

3.

Check voltage between compressor (ECV) harness connector and ground.

Is the inspection result normal?

YES

>> GO TO 12.

NO

>> GO TO 11.

11.

CHECK FUSE

(+)

(

−

)

Voltage

Compressor (ECV)

—

Connector

Terminal

F44

2

Ground

Battery voltage

HAC-132

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

INSUFFICIENT COOLING

Check power supply circuit and 10A fuse [No. 3, located in the fuse block (J/B)]. Refer to 

PG-91, "Fuse, Con-

nector and Terminal Arrangement"

.

Is the inspection result normal?

YES

>> Check harness for open circuit. Repair or replace if necessary.

NO

>> Replace fuse and check harness for short circuit. Repair or replace if necessary.

12.

CHECK ECV CONTROL SIGNAL

1.

Turn ignition switch OFF.

2.

Reconnect compressor (ECV) connector.

3.

Perform self-diagnosis. Refer to 

HAC-42, "WITHOUT LEFT AND RIGHT VENTILATION TEMPERATURE

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (Without left and right ventilation tempera-

ture separately control system) or 

HAC-48, "WITH LEFT AND RIGHT VENTILATION TEMPERATURE

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (With left and right ventilation temperature

separately control system).

4.

Set in self-diagnosis STEP-4 (Code No. 45).

5.

Confirm ECV control signal between unified meter and A/C amp
harness connector M67 terminal 65 and ground using an oscillo-
scope.

Is the inspection result normal?

YES

>> Replace compressor.

NO

>> GO TO 13.

13.

CHECK CIRCUIT CONTINUITY BETWEEN ECV AND UNIFIED METER AND A/C AMP.

1.

Turn ignition switch OFF.

2.

Disconnect compressor (ECV) connector and unified meter and A/C amp.connector.

3.

Check continuity between compressor (ECV) harness connector and unified meter and A/C amp harness
connector.

Is the inspection result normal?

YES

>> GO TO 14.

NO

>> Repair the harnesses or connectors.

14.

CHECK ECV

Check continuity between compressor (ECV) connector.

Is the inspection result normal?

YES

>> Replace the unified meter and A/C amp.

NO

>> Replace the compressor.

SJIA1765E

Compressor (ECV)

Unified meter and A/C amp.

Continuity

Connector

Terminal

Connector

Terminal

F44

3

M67

65

Existed

Compressor (ECV)

Continuity

Connector

Terminal

Connector

Terminal

F44

2

F44

3

Existed