Mitsubishi Evolution X. Manual — part 72

HEATER CONTROL

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HEATER, AIR CONDITIONING AND VENTILATION

55-8

HEATER CONTROL

M2551000900584

HEATER CONTROLLER

.

The features of the heater controller described below
have been designed for better appearance, easier
operation, and enhanced visibility.

• Each dial for the air outlet switching, fan volume

control, and temperature adjustment has been
enlarged to enhance operability.

• Ring lights have been adopted to inside the dials

to enhance appearance during nighttime.

• AUTO and OFF positions of the fan volume con-

trol dial have been exchanged with one another.
This change prevents the dial to pass the AUTO
position when the fan volume control is turned
OFF, and eliminates the necessity of manual
reselection when switching the inside/outside air
selection manually, thus enhancing the operabil-
ity.

• When the air outlet switching dial and fan volume

control dial are turned to the AUTO position, the
A/C switch has been made to automatically turn
ON to enhance convenience. (Using the custom-
ize function, this function can be cancelled. Refer
to

P.55-9

.)

AC608069

AC608068

AC708613

<Vehicles for USA>

Outside/Inside air
selection switch

Temperature adjustment knob

A/C switch

Blower knob

Mode selection knob

Rear window defogger switch

<Vehicles for CANADA>

Outside/Inside air
selection switch

Temperature
adjustment knob

Blower knob

A/C switch

Mode selection knob

Rear window
defogger switch

AB

A/C-ECU

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A/C-ECU

M2551001200403

CONTROL

.

FORCED DEF CONTROL

When air outlet position is switched to DEF, A/C is
automatically turned ON, and outside/inside air
selection damper is set to the fresh air position to
quickly defrost the windshield screen.

.

OUTLET AIR TEMPERATURE CONTROL

The engine coolant and evaporator temperature
have been additionally calibrated to stabilize the tem-
perature at vents and improve A/C controllability.

.

COOLING FAN SPEED CONTROL

According to the refrigerant pressure and the vehicle
speed, the cooling fan speed is controlled to reduce
the exterior noise and the load of the generator for
fuel economy.

.

MAX COOL, MAX HOT CONTROL

When the set temperature is at 18.0

°C <61°F>

(MAX COOL) or at 32.0

°C <89°F> (MAX HOT) with

the air outlet and air volume at the AUTO positions,
the following controls are made automatically by the
A/C-ECU.

NOTE: "*" indicates that when the automatic control
is not cancelled using the customize function, the
manual operation is disabled.

.

REAR WINDOW DEFOGGER TIMER
CONTROL

In order to prevent battery consumption, the defog-
ger is automatically turned OFF, 20 minutes after it is
turned ON.

.

IDLE-UP CONTROL

A/C-ECU and the engine ECU communicate with
each other through the CAN communication. The
idle-up speed of the engine is controlled in two steps
depending on the A/C load to secure the air cooling
performance during summer and to enhance fuel
economy in moderate seasons moderate.

.

DETECTION CONTROL FOR
REFRIGERANT LEAKS

A/C-ECU determines if the refrigerant amount is less
than specified or refrigerant pressure is abnormal by
using the ambient temperature (ambient temperature
sensor to measure refrigerant inflation rate) and
refrigerant pressure (measured by the A/C pressure
sensor). When refrigerant amount or refrigerant pres-
sure is judged abnormal, the compressor is cut-off to
protect the A/C system.
NOTE: When abnormality occurs, the A/C indicator
flashes.

.

PROTECTION CONTROL AT AIR BAG
DEPLOYMENT (DURING COLLISION)

When the air bag open is detected, the A/C system
will shut down automatically.

.

CUSTOMIZED FUNCTIONS

Depending on the user's preference, the following
functions can be adjusted. The programmed informa-
tion is held even when the battery is disconnected.

• Automatic control for inside/outside air selection

Press and hold (approximately for 10 seconds)
the inside/outside air selection switch to cancel or
resume the automatic control for inside/outside
air selection.

• A/C automatic control

Press and hold (approximately for 10 seconds)
the A/C switch to cancel or resume the A/C auto-
matic control.

COMMUNICATION

A/C-ECU performs the signal transmission and
reception with each ECU via CAN (Controller Area
Network)*. Also, with the heater control panel, it
transmits and receives signals via serial communica-
tion.
NOTE: *: For details of CAN communication, refer to
GROUP 54C

−

Controller Area Network

P.54C-2

.

Subject to
control

MAX COOL

MAX HOT

Air mix
damper

MAX COOL
position

MAX HOT
position

Air outlet
mode

FACE position

FOOT position

Air volume

Maximum

Maximum

Outside/insid
e air
selection
damper

Air recirculation
position*

Fresh air
position*

Air
conditioning
switch

ON*

OFF*

A/C COMPRESSOR

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DIAGNOSTIC FUNCTION

A/C-ECU has the following functions for easier sys-
tem checks.

• Diagnostic function

• Service data output

• Actuator test

NOTE: For each item, refer to the Workshop Manual.

A/C COMPRESSOR

M2551001100354

HIGH EFFICIENCY COMPRESSOR WITH
INTEGRATED OIL SEPARATOR

High efficiency compressor with integrated oil sepa-
rator has been adopted to enhance fuel economy by
reducing the A/C workload.

MAGNETIC CLUTCH WITH THERMAL
FUSE

At the compressor lock, the thermal fuse integrated
in the magnet clutch is blown due to the frictional
heat against the compressor in order to reduce risk
of snapping off accessory belt. The thermal fuse,
together with the coil, is coated with resin to enhance
resistance to corrosion.

2-STEP PROFILE COMPRESSOR

The center area of the scroll in the compressor pro-
vides 2-step profile, and thickness of area "B" shown
in the figure has been increased to enhance
strength. With this feature, thickness of area "A"
shown where lesser load is applied is reduced, thus
compressor performance is enhanced by compress-
ing refrigerant even in central area, comparing to the
previous model.

AC507301

a

a

b

b

A

A

B

B

AC

Section a - a

Section b - b

Front view

Front view

<Previous model>

<2-step profile
compressor>

CONDENSER

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CONDENSER

M2551001400214

The condenser has been integrated with the radiator (cooling
module) to optimize air flow and reduce weight.

DUCT

M2551001300518

The rear heater duct has been introduced, and the
air distribution ratio to front and rear seats has been
optimized in order to enhance the air heating perfor-
mance for the rear seats, and to prevent the circula-
tion of cooled air back to the front seats.

AC608768

Condenser

AB

Radiator

AC708628

To front door window
(Side defroster)

Side ventilator

Center ventilator

To windshield (Defroster)

To front door window
(Side defroster)

To passenger seat footwell

To driver seat footwell

To rear seat footwell

To rear seat footwell

Side ventilator

AB