2005 INFINITI FX35 air

ATC-72
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
Mode Door Control Specification
COMPONENT DESCRIPTION
Mode Door Motor
The mode door motor is attached to the heater & cooling unit. 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 acti-
vates the mode door.
DIAGNOSIS PROCEDURE FOR MODE DOOR MOTOR
SYMPTOM: Mode door motor does not operate normally.
Perform diagnosis procedure. Refer to AT C - 6 6 , "
DIAGNOSIS PROCEDURE FOR LAN CIRCUIT" .
RJIA1778E
RJIA0890E

TROUBLE DIAGNOSIS ATC-73
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D E
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G H
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K L
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AT C
Revision: 2005 July 2005 FX
Air Mix Door Motor CircuitAJS0014U
SYMPTOM:

Discharge air temperature does not change.

Air mix door motor does not operate normally.
INSPECTION FLOW
*1ATC-54, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 4 to 6. *2
ATC-104, "
Ambient Sensor Circuit"*3 ATC-107, "In-vehicle Sensor Circuit"
*4ATC-110, "Sunload Sensor Circuit"*5ATC-73, "Air Mix Door Motor Circuit"*6 ATC-54, "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.
*7 ATC-66, "
LAN System Circuit".*8 ATC-61, "Operational Check"*9ATC-42, "SYMPTOM TABLE"
*10ATC-113, "Intake Sensor Circuit"
SJIA0546E

ATC-74
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
SYSTEM DESCRIPTION
Component Parts
Air mix door control system components are:

Unified meter and A/C amp.

Air mix door motor (LCU)

A/C LAN system (PBR built-in mode door motor, air mix door motor and intake door motor)

In-vehicle sensor

Ambient sensor

Sunload sensor

Intake sensor
System Operation
The unified meter and A/C amp. receives data from each of the sensors. The unified meter and A/C amp.
sends air mix door, mode door and intake door motor opening angle data to the air mix door motor LCU, mode
door motor LCU and intake door motor LCU.
The air mix door motor, mode door motor and intake door motor read their respective signals according to the
address signal. Opening angle indication signals received from the unified meter and A/C amp. and each of
the motor position sensors are compared by the LCUs in each door motor with the existing decision and open-
ing angles. Subsequently, HOT/COLD, DEF/VENT and FRESH/RECIRCULATION operation is selected. The
new selection data are returned to the unified meter and A/C amp.
Air Mix Door Control Specification
RJIA1781E
RJIA1782E

TROUBLE DIAGNOSIS ATC-75
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D E
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G H
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K L
M A
B
AT C
Revision: 2005 July 2005 FX
COMPONENT DESCRIPTION
Air Mix Door Motor
The air mix door motor is attached to the heater & cooling unit. It
rotates so that the air mix door is opened or closed to a position set
by the unified meter and A/C amp. Motor rotation is then sent con-
veyed through a shaft and the air mix door position feedback is then
sent to the unified meter and A/C amp. by PBR built-in air mix door
motor.
DIAGNOSIS PROCEDURE FOR AIR MIX DOOR MOTOR
SYMPTOM: Discharge air temperature does not change.
Perform diagnosis procedure. Refer to AT C - 6 6 , "
DIAGNOSIS PROCEDURE FOR LAN CIRCUIT" .
Air Mix Door Motor PBR CircuitAJS0014V
SYMPTOM:

Discharge air temperature does not change.

PBR circuit is open or shorted.
DIAGNOSIS PROCEDURE FOR AIR MIX DOOR MOTOR PBR
Perform diagnosis procedure. Refer to AT C - 6 6 , "DIAGNOSIS PROCEDURE FOR LAN CIRCUIT" .
RJIA0893E
RJIA0894E

ATC-76
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
Intake Door Motor CircuitAJS0014W
SYMPTOM:

Intake door does not change.

Intake door motor does not operate normally.
INSPECTION FLOW
*1AT C - 5 4 , "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 4 to 6. *2
ATC-104, "
Ambient Sensor Circuit"*3 ATC-107, "In-vehicle Sensor Circuit"
*4 AT C - 11 0 , "Sunload Sensor Circuit"*5AT C - 7 3 , "Air Mix Door Motor Circuit"*6 AT C - 5 4 , "FUNCTION CONFIRMA-
TION PROCEDURE", see No. 13.
*7 AT C - 6 6 , "
LAN System Circuit"*8ATC-124, "INTAKE DOOR MOTOR"*9 AT C - 6 1 , "Operational Check"
*10 AT C - 4 2 , "SYMPTOM TABLE"*11AT C - 11 3 , "Intake Sensor Circuit"
RJIA1993E

TROUBLE DIAGNOSIS ATC-77
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D E
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G H
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K L
M A
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AT C
Revision: 2005 July 2005 FX
SYSTEM DESCRIPTION
Component Parts
Intake door control system components are:

Unified meter and A/C amp.

Intake door motor (LCU)

A/C LAN system (PBR built-in mode door motor, air mix door motor and intake door motor)

In-vehicle sensor

Ambient sensor

Sunload sensor

Intake sensor
System Operation
The intake door control determines intake door position based on the ambient temperature, the intake air tem-
perature and the in-vehicle temperature. When the DEF, or OFF switches are pressed or A/C switch is OFF,
the unified meter and A/C amp. sets the intake door at the FRESH position.
Intake Door Control Specification
RJIA1786E
RJIA1787E

ATC-78
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
COMPONENT DESCRIPTION
Intake Door Motor
The intake door motor is attached to the blower unit. It rotates so that
air is drawn from inlets set by the unified meter and A/C amp. Motor
rotation is conveyed to a lever which activates the intake door.
DIAGNOSIS PROCEDURE FOR INTAKE DOOR MOTOR
SYMPTOM: Intake door motor does not operate normally.
Perform diagnosis procedure. Refer to AT C - 6 6 , "
DIAGNOSIS PROCEDURE FOR LAN CIRCUIT" .
RJIA0897E

ATC-80
TROUBLE DIAGNOSIS
Revision: 2005 July 2005 FX
SYSTEM DESCRIPTION
Component Parts
Fan speed control system components are:

Unified meter and A/C amp.

A/C LAN system (PBR built-in mode door motor, air mix door motor and intake door motor)

In-vehicle sensor

Ambient sensor

Sunload sensor

Intake sensor
System Operation
Automatic Mode
In the automatic mode, the blower motor speed is calculated by the unified meter and A/C amp. based on the
input from the PBR, in-vehicle sensor, sunload sensor, intake sensor and ambient sensor.
When the air flow is increased, the duty ratio of the blower fan motor’s drive signal is changed at 8%/sec. to
prevent a sudden increase in air flow.
In addition to manual air flow control and the usual automatic air flow control, starting air flow control, low
water temperature starting control and high passenger compartment temperature starting control are avail-
able.
RJIA1995E