Content .. 111 112 113 114 ..

Mitsubishi Lancer Evolution VI. Manual - part 113

HEATER AND MANUAL AIR CONDITIONER –

Troubleshooting

55-4

TROUBLESHOOTING

TROUBLESHOOTING PROCEDURES

Check air ducts, control rods, etc. for improper connection.

Check that the electrical connectors of the relevant components are connected securely and the
fuse is not blown.

Perform the troubleshooting as follows; first understand the items to be inspected and the the procedures
comprehensively using Trouble Symptom/Failed Component Cross-Reference Table and then inspect
the appropriate items sequentially.

Be sure to perform each component check after disconnecting the relevant connector.

Trouble Symptom/Failed Component Cross-Reference Table

Items to be checked

1.
When the igni-
tion switch is
“ON”, the A/C
does not oper-
ate.

2.
When the A/C
is operating,
temperature
inside the pas-
senger
compartment
does not
decrease (cool
air is not
emitted).

3.
Blower fan
motor does not
turn.

4.
Blower fan
motor does not
stop turning.

5.
When A/C is
operating,
radiator fan
and condenser
fan do not run.

Fuse

Harness, connector

Amount of refrigerant

A/C compressor relay

A/C compressor magnet
clutch

Dual pressure switch

A/C switch

Blower switch

Blower relay

Resistor

Blower motor

Air thermo-sensor

Condenser fan relay

Condenser fan motor

Radiator fan relay (HI, LO)

Radiator fan motor

Refrigerant temperature
switch

Auto compressor control
unit

Engine-ECU

HEATER AND MANUAL AIR CONDITIONER –

Troubleshooting

55-5

No.

Trouble symp-
tom

Problem cause

Remedy

Refer-
ence
page

When the igni-
tion switch is
“ON”, the A/C
does not oper

Refrigerant leak or overfilling of refriger-
ant

Replenish the refrigerant, repair the
leak or take out some of the
refrigerant

55-6

does not oper-
ate.

A/C compressor relay is defective

Replace the A/C compressor relay

55-14

ate.

A/C compressor magnetic clutch is
defective

Replace the A/C compressor magnet
clutch

55-26

Dual pressure switch is defective

Replace the dual pressure switch

55-13

A/C switch is defective

Replace the A/C switch

55-17

Blower switch is defective

Replace the blower switch

55-17

Air thermo-sensor is defective

Replace the air thermo-sensor

55-22

Refrigerant temperature switch is defec-
tive

Replace the refrigerant temperature
switch

55-25

Automatic compressor-ECU is defective

Replace the automatic compressor-
ECU

–

When the A/C is
operating, tem-
perat re inside

Refrigerant leak

Replenish the refrigerant and repair
the leak

55-6

perature inside
the passenger

Dual pressure switch is defective

Replace the dual pressure switch

55-13

the passenger
compartment
doesn’t

de-

Air thermo-sensor is defective

Replace the air thermo-sensor

–

doesn t

de-

crease (cool air
is not emitted)

Condenser fan relay is defective

Replace the condenser fan relay

55-14

is not emitted).

Condenser fan motor is defective

Replace the condenser fan motor

55-29

Radiator fan relay (HI, LO) is defective

Replace the radiator fan relay (HI, LO)

55-14

Radiator fan motor is defective

Replace the radiator fan motor

–

Refrigerant temperature switch is defec-
tive

Replace the refrigerant temperature
switch

55-25

Automatic compressor-ECU is defective

Replace the automatic compressor-
ECU

–

Blower fan mo-
tor doesn’t turn

Blower switch is defective

Replace the blower switch

55-17

tor doesn’t turn.

Blower relay is defective

Replace the blower relay

55-13

Resistor is defective

Replace the resistor

55-21

Blower fan motor is defective

Replace the blower fan motor

55-21

Blower fan mo-
tor doesn’t stop
t rning

Defective harness between the blower
fan motor and the blower switch

Repair the harness

–

turning.

Blower switch is defective

Replace the blower switch

55-17

Resistor is defective

Replace the resistor

55-21

When the A/C is
operating

con

Condenser fan relay is defective

Replace the condenser fan relay

55-14

operating con-
denser fan or

Condenser fan motor is defective

Replace the condenser fan motor

55-29

denser

an or

radiator fan
does not run

Radiator fan relay (HI, LO) is defective

Replace the radiator fan relay (HI, LO)

55-14

does not run.

Radiator fan motor is defective

Replace the radiator fan motor

–

Dual pressure switch is defective

Replace the dual pressure switch

55-13

Engine-ECU is defective

Replace the engine-ECU

–

HEATER AND MANUAL AIR CONDITIONER –

Troubleshooting /
On-vehicle Service

55-6

INSPECTION AT THE AUTOMATIC COMPRESSOR-ECU TERMINAL

Terminal
No.

Check item

Checking requirements

Normal condition

Output from ECU to A/C compressor
relay

A/C compressor relay: OFF

System voltage

relay

A/C compressor relay: ON

0 V

Input from A/C switch to ECU

A/C switch: OFF

0 V

A/C switch: ON

System voltage

Earth

Always

0 V

ON-VEHICLE SERVICE

REFRIGERANT CHARGING

Caution
The refrigerant generates toxic gases when it is expored
to a heat source such as fire. Keep flames away from
the refrigerant. Perform refrigerant charging at a
well-ventilated place.

Recommended charging tools

The following commercially available tools are recommended
for discharging and charging refrigerant.

Gas charging set [No. EA95 (R134a)]

Gas charging set case [No. EA101CS-2]

Gauge manifold [No. EA101N-1]

Charging valve [No. EA108N]

Adapter valve [No. EA104AD-3]

NOTE
The adapter valve opens when the handle is turned
clockwise and closes when it is turned counter-clockwise.

Quick joint (for low pressure) [No. EA413L]

Quick joint (for high pressure) [No. EA413H]

Charging hose (red) [No. EA104N-1]

Charging hose (blue) [No. EA104N-2]

Charging hose (yellow) [No. EA104N-3]

Vacuum pump [No. EA112A]

Vacuum pump adaptor [No. EA112X]

Gauge manifold

Adapter valve
(for low pressure)

Charging hose

Vacuum
pump adaptor

Quick joint
(for low pressure)

Charging valve

Quick joint
(for high pressure)

Vacuum pump

HEATER AND MANUAL AIR CONDITIONER –

On-vehicle Service

55-7

Charging

Open the low-pressure valve of the gauge manifold. Keep
the high-pressure valve closed.

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

Connect the charging hose (blue) to the adaptor valve
1.

Connect the quick joint 2 to the charging hose (blue).

Connect the quick joint 2 to the low pressure service
valve.

NOTE
The low-pressure service valve is provided on the suction
pipe.

Caution
(1) To install the quick joint, press section “A” firmly

against the service valve until a click is heard.

(2) When connecting, run your hand along the hose

while pressing to ensure that there are no bends
in the hose.

Connect the charging hose (yellow) to the valve 3 of
the gauge manifold.

Install the vacuum pump adaptor to the vacuum pump.

Caution
To supply the power, connect the power supply plug
of the vacuum pump to the vacuum pump adapter
and then the power supply plug of the vacuum pump
adapter to a 100 V power outlet.

Connect the charging hose (yellow) to the R134a
connection port of the vacuum pump adaptor.

Tighten the adaptor valve 1 handle (valve closed).

10. 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).

11. Turn the vacuum pump adaptor switch to the R134a side

to start the vacuum pump.

Low-
pressure
valve

High-
pressure
valve

Gauge
manifold

Adapter
valve (for low
pressure)

Charging hose (yellow)

Charging hose
(blue)

To 100 V
power
outlet

Switch

R134a
connec-
tion port

Vacuum
pump
adaptor

Vacuum
pump

Power
supply
plug

Quick joint
(for low
pressure)

Low-
pressure
service
valve

Sleeve

Low-
pressure
gauge

High-
pressure
gauge

Valve

High-
pressure
service
valve

Air
condi-
tioning
system

Power
supply
plug

Switch

Content .. 111 112 113 114 ..