Mitsubishi Lancer (4A9 engine). Manual — part 301

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55A-85

9

A/C control panel (Signal)

−

−

10

− 12

−

−

−

13

Battery power supply

Always

System voltage

14

Earth

Always

1 V or less

15

IG power supply

Ignition switch: ON

System voltage

16

A/C pressure sensor input

Refer to .

Refer to .

17

Interior temperature sensor

Sensor probe temperature: 25

°C

(4.0 k

Ω)

2.1 to 2.7 V

18

−

−

−

19

Sensor earth

Always

1 V or less

20

A/C pressure sensor power
supply

Ignition switch: IG2

5 V

21

Air thermo sensor earth

Always

1 V or less

22

Air thermo sensor

Sensor probe temperature: 25

°C

(4.0 k

Ω)

2.1 to 2.7 V

23

−

−

−

24

Motor for air outside/inside
air circulation switching
damper

−

−

25

Motor for air outside/inside
air circulation switching
damper

−

−

26

Motor for air outside/inside
air circulation switching
damper

−

−

27

Motor for air outside/inside
air circulation switching
damper

−

−

28

Air mix damper motor

−

−

29

Motor power supply

−

−

30

Air outlet changeover
damper motor

−

−

31

Air outlet changeover
damper motor

−

−

32

Air outlet changeover
damper motor

−

−

33

Air outlet changeover
damper motor

−

−

34

Air mix damper motor

−

−

35

Air mix damper motor

−

−

36

Air mix damper motor

−

−

Terminal
No.

Check item

Check condition

Normal condition

ON-VEHICLE SERVICE

HEATER, AIR CONDITIONER AND VENTILATION

55A-86

ON-VEHICLE SERVICE

DRIVE BELT INSPECTION

M1552001001651

Refer to GROUP 11A

− Engine Adjustment, Drive

Belt Tension Check . <1600>
Refer to GROUP 11C

− Engine Adjustment, Drive

Belt Tension Check . <1800 Petrol engine>
Refer to GROUP 11E

− Engine Adjustment, Drive

Belt Tension Check . <2000>
Refer to GROUP 11G

− Engine Adjustment, Drive

Belt Tension Check . <1800 Diesel engine>

REFRIGERANT LEVEL CHECK,
DRAINING AND CHARGING

M1559200100312

Remove the refrigerant by the flon reclaim machine
and replenish the specified quantity of refrigerant.
NOTE: Refer to the Refrigerant Recovery and Recy-
cling Unit instruction Manual for operation of the unit.

REFILLING OF OIL IN THE A/C SYSTEM

M1552020000334

Too little oil will provide inadequate compressor lubri-
cation and cause a compressor failure. Too much oil
will increase discharge air temperature.
When a compressor is installed at the factory, it con-
tains 60 mL <Except with 1600 (M/T)> or 70 mL
<Except without 1600 (M/T)> of compressor oil.
While the A/C system is in operation, the oil is carried
through the entire system by the refrigerant. Some of
this oil will be trapped and retained in various parts of
the system.
When the following system components are
changed, it is necessary to add oil to the system to
replace the oil being removed with the component.

Compressor oil: SUN PAG 56 or S10X
Quantity

Evaporator: 25 mL
Condenser: 15 mL
Each piping: 5 mL

PERFORMANCE TEST

M1552001401057

TEST CONDITION

Item

Settings

Environment
al condition

Measurement location

In a shade or indoors

Temperature

20

°C − 50°C

Humidity

Relative humidity 30

− 80% RH

Vehicle body
condition

Hood

Fully opened

Door

Fully open for door, window, and tailgate

Air
conditioning
condition

Air conditioner switch

ON

Air volume

Maximum air volume

Temperature control

MAX COOL

Air outlet

FACE

Outside/inside air selection

Air recirculation position

Engine speed

Specified idle speed after warming up

Transmission

N or P

TEST CONDITION SETTING

Check that the temperature/humidity of measure-
ment location satisfies the test conditions, and then
set the vehicle body conditions to the designated sta-
tus according to the test conditions. If the tempera-
ture/humidity is not within the test conditions, an
accurate judgment cannot be made. Therefore, post-
pone the performance test.

ON-VEHICLE SERVICE

HEATER, AIR CONDITIONER AND VENTILATION

55A-87

COOLING PERFORMANCE CHECK

AC800067

Thermometer

AB

Wet and dry bulb
thermometer

1. Insert a thermometer into the air outlet located at

the centre of instrument panel.
NOTE: Set a thermometer so that cool air from
the air outlet blows directly against the sensing
part.

2. Set a wet and dry bulb thermometer in the air

intake of the front passenger's foot area (below
the glove box).

NOTE: Set a wet and dry bulb thermometer so
that cool air does not blow against it.

3. Start the engine to warm up. Confirm that the

engine speed of the test condition is satisfied.

4. Set the A/C control panel to the mode instructed

in the test conditions.

5. Wait until the air outlet temperature is stable

(approximately 10 minutes after the A/C starts),
and measure dry-bulb/wet-bulb temperatures at
the air outlet and the air intake.

6. If the air outlet temperature is in the range

specified by the table below, it is judged normal. If
the temperature is outside the permissible range
in the table below, refer to the refrigerant gas
pressure inspection result, and check each
section according to the diagnosis chart of
refrigerant system.

Garage ambient temperature
°C

20

25

30

35

40

45

50

Discharge air temperature

°C

4.7

−

17.3

10.0

−

22.6

15.2

−

27.9

20.4

−

33.1

25.6

−

38.4

30.9

−

43.7

36.1

−

49.0

REFRIGERANT GAS PRESSURE CHECK

CAUTION

• The temperature of equipment in the engine

room is high and the refrigerant gas pressure
is also high immediately after the engine and
A/C operation are stopped, thus leave the
vehicle for a while, and then perform the
refrigerant gas pressure check.

• On completion, stop the engine and wait until

the high-pressure side of the gauge manifold
is depressurised. Then remove the quick
joints and the others.

CAUTION

•

AC106028

A

AB

Sleeve

Place the quick joint onto the service valve, and

press to fit the part A securely until the sleeve

clicks into place.

•

AC106029

Low-pressure
valve

Gauge manifold

Charging hose (red)

Quick joint
(for high-
pressure)

Quick joint
(for low-
pressure)

AB

Charging hose (blue)

High-
pressure valve

When connecting, run your hand along the
hose while pressing to ensure that there are
no bends in the hose.

1. Check that the engine and A/C are stopped.

ON-VEHICLE SERVICE

HEATER, AIR CONDITIONER AND VENTILATION

55A-88

2. Close the high-pressure valve of the gauge

manifold.

3. Connect the charging hose (red) to the hi-

pressure side of the gauge manifold.

4. Connect the quick joint (for high pressure) to the

charging hose (red).

5. Install the quick joint (for high pressure) to the

high-pressure side service valve of the vehicle.

6. Close the low-pressure valve of the gauge

manifold.

7. Connect the charging hose (blue) to the low-

pressure side of the gauge manifold.

8. Connect the quick joint (for low pressure) to the

charging hose (blue).

9. Install the quick joint (for low pressure) to the low-

pressure side service valve of the vehicle.

10.Start and fully warm up the engine, and then

check that the engine speed of the test condition
is satisfied.

11.Set the A/C control panel to the mode instructed

in the test conditions.

12.Measure the high pressure/low pressure, and

check that the measurement is within the
permissible range of the table below. If the value
is outside the permissible range, refer to the
cooling performance check result, and perform a
check according to the diagnosis chart of
refrigerant system.
NOTE: Prior to the measurement, wait until the
refrigerant pressure is stable. (Approximately 10
minutes after A/C operation start)

Garage ambient temperature
°C

20

25

30

35

40

45

50

Compressor high pressure kPa 934

− 1,

700

1, 067

−

1, 850

1,201

−

2,000

1,335

−

2,150

1,468

−

2,300

1,602

−

2,450

1,735

−

2,600

Compressor low pressure kPa 170

−

359

215

−

406

260

−

452

305

−

499

350

−

545

395

−

592

440

−

638