Nissan Qashqai J11. Manual - part 1096

HAC-20

< SYSTEM DESCRIPTION >

[AUTOMATIC AIR CONDITIONING]

COMPONENT PARTS

• The refrigerant pressure sensor converts high-pressure side refrigerant pressure into voltage and outputs it

to ECM.

• ECM operates cooler cycle protection and cooling fan speed control according to voltage value that is input.

STRUCTURE AND OPERATION

• The refrigerant pressure sensor is a capacitance type sensor. It consists of a pressure detection area and a

signal processing area.

• The pressure detection area, which is a variable capacity condenser, changes internal static capacitance

according to pressure force.

• The signal processing area detects the static capacitance of the pressure detection area, converts the static

capacitance into a voltage value, and transmits the voltage value to ECM.

PBIB2657E

SYSTEM

HAC-21

< SYSTEM DESCRIPTION >

[AUTOMATIC AIR CONDITIONING]

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SYSTEM

AUTOMATIC AIR CONDITIONING SYSTEM

AUTOMATIC AIR CONDITIONING SYSTEM : System Description

INFOID:0000000010432170

SYSTEM DIAGRAM

DESCRIPTION

• Automatic air conditioning system is controlled by each function of A/C auto amp., ECM and IPDM E/R.
• Each operation of air conditioning system can be controlled by A/C control.

CONTROL BY A/C AUTO AMP.

•

HAC-22, "AUTOMATIC AIR CONDITIONING SYSTEM : Temperature Control"

•

HAC-23, "AUTOMATIC AIR CONDITIONING SYSTEM : Air Outlet Control"

•

HAC-23, "AUTOMATIC AIR CONDITIONING SYSTEM : Air Flow Control"

•

HAC-24, "AUTOMATIC AIR CONDITIONING SYSTEM : Air Inlet Control"

•

HAC-24, "AUTOMATIC AIR CONDITIONING SYSTEM : Compressor Control"

•

HAC-25, "AUTOMATIC AIR CONDITIONING SYSTEM : Door Control"

•

HAC-29, "AUTOMATIC AIR CONDITIONING SYSTEM : Cooling Fan Control"

•

HAC-30, "AUTOMATIC AIR CONDITIONING SYSTEM : Door Motor Starting Position Reset Control"

JMIIA3567GB

HAC-22

< SYSTEM DESCRIPTION >

[AUTOMATIC AIR CONDITIONING]

SYSTEM

• Correction for input value

Ambient temperature correction

- A/C auto amp. inputs the temperature detected by ambient sensor as the ambient temperature. 
- A/C auto amp. performs the correction of the temperature detected by ambient sensor for air conditioning

control. 

- A/C auto amp. selects and uses the initial value of ambient temperature data depending on the engine cool-

ant temperature when turning the ignition switch from OFF to ON. The detection temperature of the ambient
sensor is used when engine coolant temperature is low [less than approximately 56

°

C (133

°

F)]. The mem-

ory data (before the ignition switch is OFF) when the engine is warmed up [approximately 56

°

C (133

°

F) or

more]. 

- The correction of the ambient temperature is not performed when the detection temperature of the ambient

temperature is less than approximately 

−

20

°

C (–4

°

F). 

In-vehicle temperature correction

- A/C auto amp. inputs the temperature detected by in-vehicle sensor as the in-vehicle temperature. 
- A/C auto amp. performs the correction of the temperature detected by in-vehicle sensor for air conditioning

control. 

- A/C auto amp. performs the correction so that the recognition passenger room temperature changes

depending on the difference between the detected passenger room temperature and the recognition pas-
senger room temperature. If the difference is large, the changing is early. The changing becomes slow as
the difference becomes small. 

Intake temperature correction

- A/C auto amp. inputs the temperature detected by intake sensor as the intake temperature (evaporator tem-

perature).

- A/C auto amp. performs the correction of the temperature detected by intake sensor for air conditioning con-

trol. 

- A/C auto amp. performs the correction so that the recognition intake temperature changes depending on the

difference between the detected intake temperature and the recognition intake temperature. If the difference
is large, the changing is early. The changing becomes slow as the difference becomes small. 

Sunload amount correction

- A/C auto amp. inputs the sunload amount detected by sunload sensor. 
- A/C auto amp. performs the correction of the sunload amount detected by sunload sensor for air condition-

ing control. 

- When the sunload amount suddenly changes, for example when entering a tunnel, perform the correction so

that the recognition sunload amount of the A/C auto amp. changes slowly. 

Set temperature correction

- A/C auto amp. performs the correction to the target temperature set by the temperature control switch so as

to match the temperature felt by the passengers depending on the ambient temperature detected by ambi-
ent sensor and controls it so that the in-vehicle temperature is always the most suitable. 

CONTROL BY ECM

HAC-24, "AUTOMATIC AIR CONDITIONING SYSTEM : Compressor Control"

CONTROL BY IPDM E/R

HAC-24, "AUTOMATIC AIR CONDITIONING SYSTEM : Compressor Control"

AUTOMATIC AIR CONDITIONING SYSTEM : Temperature Control

INFOID:0000000010432171

• When ignition switch is in the ON position, A/C auto amp. always

automatically controls temperature regardless of air conditioner
operational state.

• A/C auto amp. calculates the target air mix door opening angle

depending on set temperature, in-vehicle temperature, ambient
temperature, and sunload. 

• Air mix door is controlled depending on the comparison of current

air mix door opening angle and target air mix door opening angle.

• Regardless of in-vehicle temperature, ambient temperature, and

sunload, air mix door is fixed at the fully cold position when set
temperature is 16.0

°

C, and at the fully hot position when set tem-

perature is 30.0

°

C.

JPIIA0633GB

SYSTEM

HAC-23

< SYSTEM DESCRIPTION >

[AUTOMATIC AIR CONDITIONING]

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AUTOMATIC AIR CONDITIONING SYSTEM : Air Outlet Control

INFOID:0000000010432172

• While air outlet is in automatic control, A/C auto amp. selects the

mode door position depending on a target air mix door angle and
outlet air temperature calculated from sunload.

• If ambient temperature is excessively low, D/F is selected to pre-

vent windshield fogging when air outlet is set to FOOT.

AUTOMATIC AIR CONDITIONING SYSTEM : Air Flow Control

INFOID:0000000010432173

DESCRIPTION

• A/C auto amp. changes gate voltage of power transistor and controls air flow continuously. When air flow is

increased, voltage of blower motor gradually increases to prevent a sudden increase in air flow.

• In addition to manual control and automatic control, air flow control is compose of starting fan speed control,

low coolant temperature starting control, high in-vehicle temperature starting control, and blower speed con-
trol at door motor operation.

AUTOMATIC AIR FLOW CONTROL

• A/C auto amp. decides target air flow depending on target air mix door opening angle.
• A/C auto amp. changes voltage of blower motor and controls air flow continuously so that air flow matches to

target air flow.

• When air outlet is VENT or B/L, the minimum air flow is changed

depending on sunload.

STARTING FAN SPEED CONTROL

When blower motor is activated, A/C auto amp. gradually increases voltage of blower motor to prevent a sud-
den increase in discharge air flow. [T

1 –

 T

2

 = approximately 5 seconds (for Europe and Russia), approximately

7 seconds (except for Europe and Russia)]
NOTE:
Do not perform the starting air flow control when the discharge outlet
is set to DEF.

LOW COOLANT TEMPERATURE STARTING CONTROL

JMIIA0710GB

JMIIA1129GB

JMIIA1130GB