Mitsubishi Galant (2004+). Manual - part 1703

55-1

GROUP 55

HEATER, AIR 

CONDITIONING AND 

VENTILATION

CONTENTS

GENERAL DESCRIPTION. . . . . . . . .

55-2

HEATER AND AIR CONDITIONING 
SYSTEM . . . . . . . . . . . . . . . . . . . . . . .

55-4

HEATER CONTROL  . . . . . . . . . . . . .

55-8

A/C COMPRESSOR . . . . . . . . . . . . . .

55-10

CONDENSER . . . . . . . . . . . . . . . . . . .

55-11

DUCT. . . . . . . . . . . . . . . . . . . . . . . . . .

55-11

VENTILATION SYSTEM. . . . . . . . . . .

55-12

GENERAL DESCRIPTION

HEATER, AIR CONDITIONING AND VENTILATION

55-2

GENERAL DESCRIPTION

M2551001500017

For the heater and air conditioning system, the 
heater and cooling unit are combined in a single unit, 
which, with the mode film damper and flow rate con-
trol valve in the heater unit, reduces ventilation resis-
tance, increases fan power, and reduces noise. Two 
types of air conditioner are available, manual and 
automatic.

FEATURES

.

Improvements in comfort

•

Flow rate control valve

•

Maximum A/C damper

•

Heater and blower combined into in a single unit

.

Improvements in operation performance

•

Enlargement of heater control dial

•

Enlargement of label for heater control dial

•

Electronics incorporated in temperature control 
dial and mode selection dial for heater control 
<vehicles with manual A/C>

•

A/C system display added to multi center display 
<vehicles with multi-center display (middle grade 
type)>

•

Green used for air conditioner indicator

•

Maximum A/C position added to temperature 
control dial for heater control <vehicles with man-
ual A/C>

.

Reliability

•

External temperature prioritization control for 
linked defroster control

•

New model of heater unit

•

Blower type defroster

.

Improvements in fuel economy

•

Scrolling compressor

•

Larger condenser

•

Reduced the wiring and lightened vehicle weight 
by using CAN communication system

.

Global environment protection

•

New refrigerant system

•

Detection control for refrigerant leaks

•

Integration of condenser with receiver

.

Improvements in service quality

•

Used one-shot coupling at the joints of the flexi-
ble suction hose and suction pipe

SPECIFICATIONS

ITEM

SPECIFICATION

Air conditioning switch type

Push button type

Compressor type

MSC105CA

Cooling output

5.5 kw

Heating output

5.7 kw

Refrigerant

Type

R134a (HFC-134a)

Charge quantity g (oz.)

610 

±

 20 (21.51 

±

 0.71)

GENERAL DESCRIPTION

HEATER, AIR CONDITIONING AND VENTILATION

55-3

CONSTRUCTION DIAGRAM

AC305034 AC

A/C PRESSURE SENSOR

GENERATOR

AC305246

INTERIOR 
TEMPERATURE
SENSOR

AC

<AUTOMATIC AIR CONDITIONING>

AC305245AC

<AUTOMATIC AIR CONDITIONING>

PHOTO SENSOR

AC305040AC

AMBIENT AIR 
TEMPERATURE SENSOR

AC206365

AIR THERMO SENSOR

MODE SELECTION DAMPER 
CONTROL MOTOR AND 
POTENTIOMETER

AIR MIXING DAMPER CONTROL 
MOTOR AND POTENTIOMETER

RESISTOR <MANUAL LOW TYPE>, 
POWER TRANSISTOR <MANUAL MIDDLE TYPE AND AUTO A/C>

OUTSIDE/INSIDE AIR SELECTION 
DAMPER CONTROL MOTOR

BLOWER MOTOR

AC

HEATER AND AIR CONDITIONING SYSTEM

HEATER, AIR CONDITIONING AND VENTILATION

55-4

HEATER AND AIR CONDITIONING SYSTEM

M2551001000283

AIR CONDITIONING SYSTEM

.

The following features improve maintenance, reduce vibration 
transmissibility, and improve cooling and heating performance.

•

A scrolling compressor is used for greater compression effi-
ciency of the refrigerant and improvement of cooling perfor-
mance when idling.

•

The scrolling portion of the A/C compressor was made 
more durable and longer lasting.

•

Air conditioner piping layout was simplified for fewer refrig-
erant leaks. 

•

For better maintenance, one-shot coupling is used at the 
joints of the flexible suction hose and suction pipe.

.

ONE-SHOT COUPLING
The refrigerant line maintenance was simplified by affixing the 
points of pipe connection with polymer hooks.

AC305986

HEATER UNIT

LIQUID PIPE

SUCTION PIPE

SUCTION FLEXIBLE HOSE

DISCHARGE 
FLEXIBLE HOSE

CONDENSER

A/C COMPRESSOR

AB

LOW-PRESSURE SIDE VALVE

HIGH-PRESSURE 
SIDE VALVE

CONDENSER FAN

AC209788

SUCTION 
FLEXIBLE HOSE

ONE-SHOT COUPLING

AC