Infiniti G35 (V35) Sedan. Manual - part 774

HAC-68

< FUNCTION DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

MAGNET CLUTCH CONTROL SYSTEM

MAGNET CLUTCH CONTROL SYSTEM

Description

INFOID:0000000000959927

SYSTEM DESCRIPTION

Unified meter and A/C amp. controls compressor operation by ambient temperature, intake air temperature
and signal from ECM.

Magnet Clutch Circuit

Low Temperature Protection Control

Unified meter and A/C amp. will turn compressor ON or OFF as determined by a signal detected by ambient
sensor and intake sensor.
When ambient temperature is higher than 

−

2

°

C (28

°

F), the compres-

sor turns ON. The compressor turns OFF when ambient temperature
is lower than 

−

5

°

C (23

°

F).

When intake air temperature is higher than 1

°

C (34

°

F), the compres-

sor turns ON. The compressor turns OFF when intake air tempera-
ture is lower than 

−

5

°

C (23

°

F).

JSIIA0141GB

RHA094GB

SJIA0267E

MODE DOOR MOTOR

HAC-69

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

COMPONENT DIAGNOSIS

MODE DOOR MOTOR

Description

INFOID:0000000000959928

COMPONENT DESCRIPTION

Mode Door Motor

The mode door motor (1) are attached to the heater & cooling unit
assembly. It rotates so that air is discharged from the outlet set by
the unified meter and A/C amp. Motor rotation is conveyed to a link
which activates the mode door.

Component Function Check

INFOID:0000000000959929

1.

CONFIRM SYMPTOM BY PERFORMING THE FOLLOWING OPERATIONAL CHECK

1.

Press MODE switch(es) and DEF switch.

2.

Each position indicator should change shape.

3.

Confirm that discharge air comes out according to the air distribution table at below. Refer to 

HAC-23,

"WITHOUT LEFT AND RIGHT VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM :
System Description"

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

HAC-32,

"WITH LEFT AND RIGHT VENTILATION TEMPERATURE SEPARATELY CONTROL SYSTEM : System
Description"

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

NOTE:
Confirm that the compressor clutch is engaged (Sound or visual inspection) and intake door position is at FRE
when DEF 

 or D/F 

 is selected.

Is the inspection result normal?

YES

>> END.

NO

>> Go to diagnosis procedure. Refer to 

HAC-69, "Diagnosis Procedure"

.

Diagnosis Procedure

INFOID:0000000000959930

1.

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"

 (With 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 2.

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.

2.

PERFORM SELF-DIAGNOSIS STEP-3

Perform self-diagnosis STEP-3. 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) 

HAC-50, "WITH LEFT AND RIGHT VENTILATION TEMPERATURE

:

Vehicle front

JSIIA0005GB

HAC-70

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

MODE DOOR MOTOR

SEPARATELY CONTROL SYSTEM : Diagnosis Description"

 (With left and right ventilation temperature sepa-

rately control system), see No. 1 to 3.
Does code No. 30 appear on the display?

YES

>> GO TO 8.

NO-1

>> Code No. 31 or 32 appear on the display: GO TO 3.

NO-2

>> Code No. 37, 38 or 39 appear on the display: Go to Intake Door Motor Circuit. Refer to 

HAC-80,

"Diagnosis Procedure"

.

3.

CHECK POWER SUPPLY FOR UNIFIED METER AND A/C AMP.

1.

Turn ignition switch ON.

2.

Check voltage between unified meter and A/C amp. harness connector M67 terminal 70 and ground.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Replace unified meter and A/C amp.

4.

CHECK SIGNAL FOR UNIFIED METER AND A/C AMP.

Confirm A/C LAN signal between unified meter and A/C amp. harness connector M67 terminal 69 and ground
using an oscilloscope.

Is the inspection result normal?

YES

>> GO TO 5.

NO

>> Replace unified meter and A/C amp.

5.

CHECK POWER SUPPLY FOR MODE DOOR MOTOR

Check voltage between mode door motor harness connector M253 terminal 1 and ground.

Is the inspection result normal?

YES

>> GO TO 6.

NO

>> Repair harness or connector.

6.

CHECK SIGNAL FOR MODE DOOR MOTOR

Confirm A/C LAN signal between mode door motor harness connector M253 terminal 3 and ground using an
oscilloscope.

(+)

(

−

)

Voltage

Unified meter and A/C amp.

—

Connector

Terminal

M67

70

Ground

Battery voltage

(+)

(

−

)

Voltage

Unified meter and A/C amp.

—

Connector

Terminal

M67

69

Ground

SJIA1453J

(+)

(

−

)

Voltage

Mode door motor

—

Connector

Terminal

M253

1

Ground

Battery voltage

MODE DOOR MOTOR

HAC-71

< COMPONENT DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

C

D

E

F

G

H

J

K

L

M

A

B

HAC

N

O

P

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Repair harness or connector.

7.

CHECK MODE DOOR MOTOR GROUND CIRCUIT

1.

Turn ignition switch OFF.

2.

Disconnect mode door motor connector.

3.

Check continuity between mode door motor harness connector M253 terminal 2 and ground.

Is the inspection result normal?

YES

>> Replace mode door motor.

NO

>> Repair harness or connector.

8.

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) 

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

>> END.

NO

>> GO TO 9.

9.

CHECK MODE DOOR CONTROL LINKAGE

Check mode door control linkage.
Is it installed normally?

YES

>> Refer to 

VTL-38, "Exploded View"

.

NO

>> Repair or adjust control linkage.

(+)

(

−

)

Voltage

Mode door motor

—

Connector

Terminal

M253

3

Ground

SJIA1453J

(+)

(

−

)

Continuity

Mode door motor

—

Connector

Terminal

M253

2

Ground

Continuity should exist