Nissan Qashqai (2007-2010). Manual - part 920

HAC-40

< FUNCTION DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

AIR MIX DOOR CONTROL SYSTEM

LAN System Circuit

Air Mix Door Control Specification

When ignition switch is ON, auto amp. continuously and automati-
cally controls temperatures regardless of air conditioner operational
condition. When setting a target temperature with temperature con-
trol dial, auto amp. corrects the set temperature and decides a target
air mix door opening angle. Auto amp. controls air mix door accord-
ing to the target air mix door opening angle and current air mix door
opening angle in order to keep an optimum air mix door opening
angle. When a temperature is set at 16.0

°

C, air mix door is fixed at

full cold, and when a temperature is set at 30.0

°

C, it is set at full hot.

JPIIA0122GB

RHA457H

INTAKE DOOR CONTROL SYSTEM

HAC-41

< FUNCTION DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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INTAKE DOOR CONTROL SYSTEM

Description

INFOID:0000000000954640

SYSTEM DESCRIPTION

Component Parts

Intake door control system components are:

• Auto amp.
• Intake door motor (LCU)
• A/C LAN system (PBR built-in mode door motor, high-level ventilator door motor, air mix door motor and

intake door motor)

• In-vehicle sensor
• OAT sensor
• Sunload sensor
• Intake sensor

System Operation

• The auto amp. receives data from each of the sensors.
• The auto amp. sends air mix doors, mode door, high-level ventilator door and intake door opening angle

data to the air mix door motor LCUs, mode door motor LCU, high-level ventilator door motor LCU and intake
door motor LCU.

• The air mix door motors, mode door motor, high-level ventilator door motor and intake door motor read their

respective signals according to the address signal. Opening angle indication signals received from the auto
amp. and each of the motor position sensors are compared by the LCUs in each door motor with the existing
decision and opening angles.

• Subsequently, HOT/COLD, DEF/VENT, OPEN/SHUT and FRE/REC operation is selected. The new selec-

tion data are returned to the auto amp.

• The intake door control determines intake door position based on the ambient temperature, the intake air

temperature and the in-vehicle temperature. When shifting mode position D/F, when the DEF or OFF
switches are pressed, or when A/C switch is OFF, the auto amp. sets the intake door at the FRE position.

JPIIA0166GB

HAC-42

< FUNCTION DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

INTAKE DOOR CONTROL SYSTEM

LAN System Circuit

Intake Door Control Specification

Intake door position is basically fixed at FRE when FRE indicator
lamps of DEF switch and intake switch turn ON, and fixed at REC
when REC indicator lamp of intake switch turns ON.
Intake door automatic control selects FRE, 20%FRE, or REC
depending on a target air mix door opening angle, based on in-vehi-
cle temperature, ambient temperature, and sunload.

JPIIA0122GB

RHA383H

BLOWER MOTOR CONTROL SYSTEM

HAC-43

< FUNCTION DIAGNOSIS >

[AUTOMATIC AIR CONDITIONER]

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BLOWER MOTOR CONTROL SYSTEM

Description

INFOID:0000000000954641

SYSTEM DESCRIPTION

Component Parts

Fan speed control system components are:

• Auto amp.
• A/C LAN system (PBR built-in mode door motor, air mix door motors and intake door motor)
• In-vehicle sensor
• OAT sensor
• Sunload sensor
• Intake sensor

System Operation

Blower motor circuit

Automatic Mode

In the automatic mode, the blower motor speed is calculated by the auto amp. based on the input from the
PBR, in-vehicle sensor, sunload sensor, intake sensor and OAT sensor.
The blower motor applied voltage ranges from approximately 4 V (lowest speed) to 12 V (highest speed).
The control blower speed (in the range of 4 to 12 V), auto amp. supplies a gate voltage to the fan control amp. 
Based on this voltage, fan control amp. control voltage supplied to the blower motor.

Starting Fan Speed Control

Start up from COLD SOAK Condition (Automatic mode)
In a cold start up condition where the engine coolant temperature is below 56

°

C (133

°

F), the blower will not

operate for a short period of time (up to 150 seconds). The exact start delay time varies depending on the
ambient and engine coolant temperature.

JPIIA0167GB

JPIIA0168GB