Nissan Quest E52. Manual - part 758

HAC-162

< SYSTEM DESCRIPTION >

[MANUAL AIR CONDITIONING]

SYSTEM

SYSTEM

FRONT MANUAL AIR CONDITIONING SYSTEM

FRONT MANUAL AIR CONDITIONING SYSTEM : System Description

INFOID:0000000009652625

SYSTEM DIAGRAM

DESCRIPTION

• Front manual air conditioning system is controlled by each function of A/C amp., BCM, ECM and IPDM E/R.
• Each operation of front air conditioning can be controlled by front A/C control (built-in A/C amp.).

CONTROL BY A/C AMP.

•

HAC-163, "FRONT MANUAL AIR CONDITIONING SYSTEM : Air Flow Control"

•

HAC-163, "FRONT MANUAL AIR CONDITIONING SYSTEM : Air Inlet Control"

•

HAC-163, "FRONT MANUAL AIR CONDITIONING SYSTEM : Compressor Control"

•

HAC-164, "FRONT MANUAL AIR CONDITIONING SYSTEM : Door Control"

• Correction for input value

Intake temperature correction

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

perature).

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

trol. 

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

ference 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. 

CONTROL BY BCM

•

HAC-163, "FRONT MANUAL AIR CONDITIONING SYSTEM : Compressor Control"

CONTROL BY ECM

•

HAC-163, "FRONT MANUAL AIR CONDITIONING SYSTEM : Compressor Control"

JMIIA1789GB

SYSTEM

HAC-163

< SYSTEM DESCRIPTION >

[MANUAL AIR CONDITIONING]

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• Cooling fan control. Refer to 

EC-45, "COOLING FAN CONTROL : System Description"

.

CONTROL BY IPDM E/R

•

HAC-163, "FRONT MANUAL AIR CONDITIONING SYSTEM : Compressor Control"

• Cooling fan control. Refer to 

PCS-5, "RELAY CONTROL SYSTEM : System Description"

.

FRONT MANUAL AIR CONDITIONING SYSTEM : Air Flow Control

INFOID:0000000009652626

DESCRIPTION

• A/C amp. changes duty ratio of front blower motor control signal to control air flow continuously. When air

flow is increased, duty ratio of front blower motor control signal gradually increases to prevent a sudden
increase in air flow.

• In addition to manual control, air flow control is compose of fan speed control at door motor operation.

FAN SPEED CONTROL AT DOOR MOTOR OPERATION

When front mode door motor is activated while air flow is more than the specified value, A/C amp. reduces
temporarily fan speed so that front mode door moves smoothly.

FRONT MANUAL AIR CONDITIONING SYSTEM : Air Inlet Control

INFOID:0000000009652627

A/C amp. controls air inlet to fresh air intake (FRE), when engine coolant temperature is 105

°

C (221

°

F) or

more.

FRONT MANUAL AIR CONDITIONING SYSTEM : Compressor Control

INFOID:0000000009652628

DESCRIPTION

• When the compressor activation condition is satisfied while front blower motor is activated, A/C amp. trans-

mits A/C ON signal and blower fan ON signal to BCM.

• BCM transmits the A/C ON signal and blower fan ON signal to ECM via CAN communication line. Refer to

BCS-12, "SIGNAL BUFFER SYSTEM : System Description"

.

• ECM judges the conditions of each sensor (refrigerant pressure sensor signal, accelerator position signal,

etc.), and transmits the A/C compressor request signal to IPDM E/R via CAN communication line.

• By receiving the A/C compressor request signal from ECM, IPDM E/R turns the A/C relay to ON, and acti-

vates the compressor. Refer to 

PCS-5, "RELAY CONTROL SYSTEM : System Description"

.

CONTROL BY A/C AMP.

Low Temperature Protection Control

When intake sensor detects that front evaporator fin temperature is
2.5

°

C (37

°

F) or less, A/C amp. requests ECM to turn the compressor

OFF, and stops the compressor.
When the front evaporator fin temperature returns to 4.0

°

C (39

°

F) or

more, the compressor is activated.

CONTROL BY ECM

Compressor Protection Control at Pressure Malfunction

When the high-pressure side value that is detected by refrigerant pressure sensor is as per the following state,
ECM requests IPDM E/R to turn A/C relay OFF and stops the compressor.
• 3.12 MPa (31.8 kg/cm

2

, 452 psi) or more (When the engine speed is less than 1,500 rpm)

• 2.74 MPa (27.9 kg/cm

2

, 397 psi) or more (When the engine speed is 1,500 rpm or more)

• 0.14 MPa (1.4 kg/cm

2

, 20 psi) or less

Compressor Oil Circulation Control

When the engine starts while the engine coolant temperature is 56

°

C (133

°

F) or less, ECM activates the com-

pressor for approximately 6 seconds and circulates the compressor oil once.

JMIIA1774GB

HAC-164

< SYSTEM DESCRIPTION >

[MANUAL AIR CONDITIONING]

SYSTEM

Air Conditioning Cut Control

When the engine condition is high load, ECM transmit A/C relay OFF request to IPDM E/R, and stops the
compressor. Refer to 

EC-43, "AIR CONDITIONING CUT CONTROL : System Description"

.

FRONT MANUAL AIR CONDITIONING SYSTEM : Door Control

INFOID:0000000009652629

DOOR MOTOR CONTROL

• LCU (Local Control Unit) is built into each door motor. And detects door position by PBR (Potentio Balance

Resistor). 

• A/C amp. communicates with each LCU via communication line. And receives each door position feedback

signal from each LCU.

• Each LCU controls each door to the appropriate position depending on the control signal from A/C amp. 
• Each LCU transmits the signal of door movement completion to A/C amp., when the door movement is com-

pleted.

SWITCH AND THEIR CONTROL FUNCTION

JMIIA1777GB

JMIIA1778ZZ

SYSTEM

HAC-165

< SYSTEM DESCRIPTION >

[MANUAL AIR CONDITIONING]

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AIR DISTRIBUTION

1.

Intake door

2.

Front blower motor

3.

In-cabin microfilter

4.

Front evaporator

5.

Front air mix door

6.

Front heater core

7.

Foot door

8.

Ventilator door

9.

Defroster door

10. Max. cool door

Fresh air

Recirculation air

Discharge air

Defroster

Center ventilator

Side ventilator

Front foot

Rear foot

Switch position

Door position

Front mode door

In

ta

ke

 do

or

Fro

n

t ai

r m

ix 

do

or

V

e

nt

ila

to

r do

or

Ma

x. co

ol

 d

o

o

r

Def

ros

te

r do

or

Fo

ot

 do

or

MODE switch

A

A

A

A

—

—

B

B

A

B

C

C

B

B

C

B

B

B

DEF switch

C

A

C

C

REC switch

—

—

—

—

A

FRE switch

B

Temperature control switch

Full cold

—

A

Full hot

B

ON·OFF switch

OFF

C

C

B

B

—

Discharge air flow

MODE/DEF set po-

sition

Air outlet/distribution

Ventilator

Foot

Defroster

Center

Side

Front

Rear

50%

50%

—

—

26%

30%

30%

14%

—

—

14%

40%

16.5%

29.5%

—

14%

35%

16%

35%

—

12%

—

88%