Infiniti G35 (V35). Manual - part 102

TROUBLE DIAGNOSIS

ATC-79

ATC

Blower Speed Compensation

Sunload
When the in-vehicle temperature and the set temperature are very close, the blower will be operating at low
speed. The low speed will vary depending on the sunload. During conditions of low or no sunload, the blower
low speed is at duty ratio 25%. During high sunload conditions, the display and A/C auto amp. raise the blower
speed (duty ratio 49%).

Fan Speed Control Specification

COMPONENT DESCRIPTION
Brush-less Motor

The blower motor utilizes a brush-less motor with a rotating magnet.
Quietness is improved over previous motors where the brush was
the point of contact and the coil rotated.

DIAGNOSIS PROCEDURE FOR BLOWER MOTOR

SYMPTOM: Blower motor operation is malfunctioning.

RJIA1609E

ZHA152H

RJIA3509E

ATC-80

TROUBLE DIAGNOSIS

CHECK POWER SUPPLY FOR BLOWER MOTOR

Disconnect blower motor connector.

Turn ignition switch ON.

Check voltage between blower motor harness connector M62
terminal 1 and ground.

OK or NG

>> GO TO 2.

>> Check power supply circuit and 15A fuses [Nos. 10 and

11, located in the fuse block (J/B)]. Refer to

PG-73,

"FUSE BLOCK - JUNCTION BOX (J/B)"

●

If fuses are OK, check harness for open circuit. Repair or replace if necessary.

●

If fuses are NG, check harness for short circuit and replace fuse.

CHECK GROUND CIRCUIT FOR BLOWER MOTOR

Turn ignition switch OFF.

Check continuity between blower motor harness connector M62
terminal 3 and ground.

OK or NG

>> GO TO 3.

>> Repair harness or connector.

CHECK CIRCUIT CONTINUITY BLOWER MOTOR AND DISPLAY AND A/C AUTO AMP.

Disconnect display and A/C auto amp. connector.

Check continuity between blower motor harness connector M62
terminal 2 and display and A/C auto amp. harness connector
M31 terminal 25.

OK or NG

>> GO TO 4.

>> Repair harness or connector.

1 – Ground

: Battery voltage

RJIA1997E

3 – Ground

: Continuity should exist.

RJIA1998E

2 – 25

: Continuity should exist.

RJIA3510E

TROUBLE DIAGNOSIS

ATC-81

ATC

CHECK DISPLAY AND A/C AUTO AMP. OUTPUT SIGNAL

Reconnect blower motor connector and display and A/C auto
amp. connector.

Turn ignition switch ON.

Change the fan speed from Lo to Hi, and check the duty ratios
between blower motor harness connector M62 terminal 2 and
ground by using an oscilloscope. Normal terminal 2 drive signal
duty ratios are shown in the table below.

OK or NG

>> Replace blower motor after confirming the fan air flow does not change.

>> Replace display and A/C auto amp.

COMPONENT INSPECTION
Blower Motor

Confirm smooth rotation of the blower motor.

●

Ensure that there are no foreign particles inside the blower unit.

RJIA2000E

RJIA3511E

RJIA0905E