Infiniti G35 (V35) Sedan. Manual - part 787

HAC-120

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

INSUFFICIENT COOLING

NO

>> Go to appropriate malfunctioning sensor circuit. Refer to 

HAC-44, "WITHOUT LEFT AND RIGHT

VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

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

HAC-50, "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-44, "WITHOUT LEFT AND RIGHT VENTILATION TEMPERA-

TURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (Without left and right ventilation tempera-

ture separately control system) or 

HAC-50, "WITH LEFT AND RIGHT VENTILATION TEMPERATURE

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (With left and right ventilation temperature sepa-

rately control system), see No.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-44, "WITHOUT LEFT AND RIGHT VENTILATION TEMPERA-

TURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (Without left and right ventilation tempera-

ture separately control system) or 

HAC-50, "WITH LEFT AND RIGHT VENTILATION TEMPERATURE

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (With left and right ventilation temperature sepa-

rately control system), see No.1 to 10.
Is the inspection result normal?

YES

>> GO TO 8.

NO

>> Go to appropriate malfunctioning sensor circuit. Refer to 

HAC-44, "WITHOUT LEFT AND RIGHT

VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

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

HAC-50, "WITH LEFT

AND RIGHT VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Diagnosis
Description"

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

8.

CHECK A/C COMPRESSOR BELT

Check the A/C compressor belt. Refer to 

EM-12, "Checking"

.

Is the inspection result normal?

YES

>> GO TO 9.

NO

>> Adjust or replace the A/C compressor 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 F43 terminal 2 and ground.

Is the inspection result normal?

YES

>> GO TO 12.

NO

>> GO TO 11.

11.

CHECK FUSE

(+)

(

−

)

Voltage

Compressor (ECV)

—

Connector

Terminal

F43

2

Ground

Battery voltage

INSUFFICIENT COOLING

HAC-121

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

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

PG-93, "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-44, "WITHOUT LEFT AND RIGHT VENTILATION TEMPERATURE

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (Without left and right ventilation tempera-

ture separately control system) or 

HAC-50, "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 F43 terminals 3 and unified meter and A/
C amp harness connector M67 terminal 65.

Is the inspection result normal?

YES

>> GO TO 14.

NO

>> Repair the harnesses or connectors.

14.

CHECK ECV

Check continuity between compressor (ECV) connector F43 terminals 2 and 3.

Is the inspection result normal?

YES

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

NO

>> Replace the compressor.

SJIA1765E

(+)

(

−

)

Continuity

Compressor (ECV)

Unified meter and A/C amp.

Connector

Terminal

Connector

Terminal

F43

3

M67

65

Continuity should exist

(+)

(

−

)

Continuity

Mode door motor

Mode door motor

Connector

Terminal

Connector

Terminal

M253

2

F43

3

Continuity should exist

HAC-122

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

INSUFFICIENT HEATING

INSUFFICIENT HEATING

Description

INFOID:0000000000959977

Symptom

• Insufficient heating
• No warm air comes out. (Air flow volume is normal.)

Inspection procedure

INFOID:0000000000959978

1.

CHECK COOLING SYSTEM

1.

Check engine coolant level and check for leakage. Refer to 

CO-8, "Inspection"

.

2.

Check radiator cap. Refer to 

CO-12, "RADIATOR CAP : Inspection"

.

3.

Check water flow sounds of engine coolant. Refer to 

CO-9, "Refilling"

.

Is the inspection result normal?

YES

>> GO TO 2.

NO

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

2.

CHECK SETTING OF TEMPERATURE SETTING TRIMMER

1.

Check the setting of temperature setting trimmer. Refer to 

HAC-5, "WITHOUT LEFT AND RIGHT VENTI-

LATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Description & Inspection"

 (Without left

and right ventilation temperature separately control system) or 

HAC-9, "WITH LEFT AND RIGHT VENTI-

LATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Description & Inspection"

 (With left and

right ventilation temperature separately control system).

2.

Check that the temperature setting trimmer is set to “

−

 direction”. 

NOTE:
The control temperature can be set with the setting of temperature setting trimmer.

3.

Set temperature control dial to “0”.

Are the symptoms solved?

YES

>> Perform the setting separately if necessary. END.

NO

>> GO TO 3.

3.

CHECK OPERATION

1.

Turn temperature dial (driver side) and raise temperature setting to 32

°

C (90

°

F) after warming up the

engine.

2.

Check that warm air blows from outlets.

Is the inspection result normal?

YES

>> END.

NO

>> GO TO 4.

4.

PERFORM SELF-DIAGNOSIS STEP-2

Perform self-diagnosis STEP-2. Refer to 

HAC-44, "WITHOUT LEFT AND RIGHT VENTILATION TEMPERA-

TURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (Without left and right ventilation tempera-

ture separately control system) or 

HAC-50, "WITH LEFT AND RIGHT VENTILATION TEMPERATURE

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (Witt left and right ventilation temperature sepa-

rately control system), see No. 1 to 2.

Does code No. 20 appear on the display?

YES

>> GO TO 5.

NO

>> Go to appropriate malfunctioning sensor circuit. Refer to 

HAC-44, "WITHOUT LEFT AND RIGHT

VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

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

HAC-50, "WITH LEFT

AND RIGHT VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Diagnosis
Description"

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

5.

PERFORM SELF-DIAGNOSIS STEP-4

Perform self-diagnosis STEP-4. Refer to 

HAC-44, "WITHOUT LEFT AND RIGHT VENTILATION TEMPERA-

TURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (Without left and right ventilation tempera-

ture separately control system) or 

HAC-50, "WITH LEFT AND RIGHT VENTILATION TEMPERATURE

INSUFFICIENT HEATING

HAC-123

< SYMPTOM DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (With left and right ventilation temperature sepa-

rately control system), see No. 1 to 5.
Is it installed normally?

YES

>> GO TO 6.

NO

>> Perform the diagnosis applicable to each output device. 

6.

PERFORM SELF-DIAGNOSIS STEP-5

Perform self-diagnosis STEP-5. Refer to 

HAC-44, "WITHOUT LEFT AND RIGHT VENTILATION TEMPERA-

TURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (Without left and right ventilation tempera-

ture separately control system) or 

HAC-50, "WITH LEFT AND RIGHT VENTILATION TEMPERATURE

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (With left and right ventilation temperature sepa-

rately control system).
Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Go to appropriate malfunctioning sensor circuit. Refer to 

HAC-44, "WITHOUT LEFT AND RIGHT

VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Diagnosis Description"

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

HAC-50, "WITH LEFT

AND RIGHT VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : Diagnosis
Description"

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

7.

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 8.

NO

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

8.

CHECK HEATER HOSE INSTALLATION CONDITION

Check the heater hose installation condition visually (for twist, crush, etc.).

Is the inspection result normal?

YES

>> GO TO 9.

NO

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

9.

CHECK TEMPERATURE OF HEATER HOSE

1.

Check the temperature of inlet hose and outlet hose of heater core.

2.

Check that the inlet side of heater core is hot and the outlet side is slightly lower than/almost equal to the
inlet side.

CAUTION:

The temperature inspection should be performed in a short time because the engine coolant tem-
perature is too hot.

Is the inspection result normal?

YES

>> GO TO 10.

NO

>> Replace the heater core after performing the procedures after the cooling system inspection

again. GO TO 1.

10.

REPLACE HEATER CORE

Replace the heater core. Refer to heater core. Refer to 

VTL-43, "Removal and Installation"

.

Are the symptoms solved?

YES

>> END

NO

>> Perform the procedures after the cooling system inspection again. GO TO 1.