Mitsubishi Pajero Pinin. Manual - part 364

HEATER, AIR CONDITIONER AND VENTILATION

 – 

Troubleshooting

55-7

INSPECTION AT THE ENGINE-ECU TERMINAL

Terminal
No.

Check item

Checking requirements

Normal condition

21

Fan controller output

A/C switch: OFF

5 V

A/C switch: ON

0 V

8*

1

22*

2

A/C compressor output

A/C compressor relay: OFF

0 V

22*

2

A/C compressor relay: ON

System voltage

45

A/C switch input

A/C switch: OFF

0 V

A/C switch: ON

System voltage

73*

1
2

Air thermosensor earth

Air thermosensor detection temperature: 25

_

C

2.0 – 2.9 V

73
77*

2

Air thermosensor earth

Air thermosensor detection tem erature: 25 C

2.0   2.9 V

92

Air thermosensor input

Always

0 V

NOTE
*

1

: Vehicles with immobilizer

*

2

: Vehicles without immobilizer

*

3

: Vehicles for Hong Kong

*

4

: Except vehicles for Hong Kong

HEATER, AIR CONDITIONER AND VENTILATION

 – 

On-vehicle Service

55-8

ON-VEHICLE SERVICE 

REFRIGERANT LEVEL TEST THROUGH
PERFORMANCE TEST

1.

Park the vehicle to be tested in a place that is not in
direct sunlight.

2.

Set conditions for outside air temperature as follows:
Dry-bulb temperature: 22

_

C 

or more

Relative humidity:

 

60 to 100%

3.

Close all of the doors with the windows fully closed.

4.

Close the valves of the gauge manifold.

5.

Connect the charging hose (red) to the gauge manifold
(high-pressure side) and the quick joint (for high-pressure)
to the end of the hose.

6.

Connect the charging hose (blue) to the gauge manifold
(low-pressure side) and the quick joint (for low-pressure)
to the end of the hose.

7.

Connect the quick joints to the appropriate service valves
of the vehicle.
Caution
To connect the quick joint, press section “A” firmly
against the service valve until a click is heard.
When connecting, run your hand along the hose while
pressing the section “A” to ensure that there are no
bends in the hose.

8.

Start the engine.

9.

Turn the blower switch to HI position.

10. Turn on the A/C switch, and set the A/C control to MAX.

COOL.

11. Set the air outlet changeover to FACE mode and the inside

air/outside air changeover to the inside air recirculation
mode.

12. Adjust the engine speed to 1,500 r/min.

13. Check if the outside air temperature and air temperature

blown out of FACE duct, and the outside air temperature
and refrigerant pressure (high-pressure and low-pressure
sides) are within the normal value range shown in the
graphs.

14. If the temperature and pressure are below the given range,

replenish the refrigerant. If above, drain the refrigerant.
(For charging, refer to P.55-10.)

NOTE
In the graph below, see the following:
[A]: Refrigerant pressure (high-pressure side)
[B]: Refrigerant pressure (low-pressure side)

Low-pressure
valve

High-pressure valve

Gauge manifold

Charging
hose (red)

Charging-
hose (blue)

Quick joint (for
low-pressure)

Quick joint 
(for high-pressure)

Sleeve

A

High-pressure or-
low-pressure ser-
vice valve

Low-
pressure
service
valve

High-
pressure
service
valve

A/C system

15

20

25

30

(

_

C)

35

40

Air temperature out of FACE duct (

_

C)

0

4

8

12

16

Normal

Outside air temperature

High-pressure side

Low-pressure side

15

20

25

30

(

_

C)

35

40

490

981

1471

1961

2452

2942

0

kPa

kPa

98

196

294

392

490

588

0

686

Outside air temperature

[A]

[B]

HEATER, AIR CONDITIONER AND VENTILATION

 – 

On-vehicle Service

55-9

MAGNETIC CLUTCH TEST

1.

Disconnect the connector (1-pin) to the magnetic clutch.

2.

Connect battery (+) voltage directly to the connector for
the magnetic clutch.

3.

If the magnetic clutch is normal, there will be “click”. If
the pulley and armature do not make contact (‘click’), there
is a malfunction.

RECEIVER DRIER TEST

Operate the unit and check the piping temperature by touching
the receiver drier outlet and inlet.
If there is a difference in the temperatures, the receiver drier
is restricted.
Replace the receiver drier.

COMPRESSOR DRIVE BELT ADJUSTMENT

Refer to GROUP 11 – On-vehicle Service.

DUAL PRESSURE SWITCH CHECK

1.

Remove the dual pressure switch connector and connect
the high/low pressure side terminals located on the harness
side as shown in the illustration.

2.

Install a gauge manifold to the high

-

pressure side service

valve of the refrigerant line. (Refer to Performance Test.)

3.

When the high/low pressure sides of the dual pressure
switch are at operation pressure (ON) and there is
continuity between the respective terminals, then the
condition is normal. If there is no continuity, replace the
switch.

ON

177 

"

 20

kPa

LOW-PRESSURE
SIDE

HIGH-PRESSURE
SIDE

186 

"

 20

OFF

Dual pressure
switch

2,650

"

 200

2,050

"

 200

HEATER, AIR CONDITIONER AND VENTILATION

 – 

On-vehicle Service

55-10

CHARGING

1.

With the handles turned back all the way (valve closed),
install the adaptor valve to the low-pressure side of the
gauge manifold.

2.

Connect the charging hose (blue) to the adaptor valve.

3.

Connect the quick joint (for low

-

pressure) to the charging

hose (blue).

4.

Connect the quick joint (for low

-

pressure) to the low

-

pressure service valve.

NOTE
The low-pressure service valve should be connected to
the suction hose.

Caution
(1) Use tools that are suited to R-134a.
(2) To install the quick joint, press section “A” firmly

against the service valve until a click is heard.
When connecting, run your hand along the hose
while pressing to ensure that there are no bends
in the hose.

5.

Close the high and low

-

pressure valves of the gauge

manifold.

6.

Install the vacuum pump adaptor to the vacuum pump.

7.

Connect the vacuum pump plug to the vacuum pump
adaptor.

8.

Connect the charging hose (yellow) to the R-134a
connection port of the vacuum pump adaptor.

9.

Tighten the adaptor valve handle (valve open).

10. Open the low

-

pressure valve of the gauge manifold.

11. Turn the power switch of the vacuum pump to the ON

position.

NOTE
Even if the vacuum pump power switch is turned ON,
the vacuum pump will not operate because of the power
supply connection in step (7).

Low-pressure
valve

High-pressure
valve

Gauge manifold

Adapter
valve

Charging hose
(yellow)

Charging hose
(blue)

R-12 con-
nection
port

Switch

R-134a
connection
port

Vacuum
pump
adaptor

Vacuum
pump

Power supply
plug

Switch

Quick
joint (for
low pres-
sure)

Low-pressure
service valve

Sleeve

A