Mitsubishi Montero (1991+). Manual — part 21

Switch Position Terminal Numbers Continuity

Colt Vista

OFF . . . . . . . 1-7 . . . . . No

Low . . . . . .. 1, 2 & 7 . . . .. Yes

Medium 1 . . . . ... 2 & 4 . . . ... Yes

Medium 2 . . . . ... 2 & 5 . . . ... Yes

High . . . . . ... 2 & 6 . . . ... Yes

Montero

OFF . . . . . . . 1-7 . . . . . No

Low . . . . . .. 1, 2 & 7 . . . .. Yes

Medium 1 . . . . . 2, 4 & 7 . . . .. Yes

Medium 2 . . . . . 1, 5 & 7 . . . .. Yes

High . . . . . . 2, 6 & 7 . . . .. Yes

Pickup & Ram-50

OFF . . . . . . . 1-6 . . . . . No

Low . . . . . .. 1, 2 & 6 . . . .. Yes

Medium 1 . . . . . 1, 3 & 6 . . . .. Yes

Medium 2 . . . . . 1, 4 & 6 . . . .. Yes

High . . . . . . 1, 5 & 6 . . . .. Yes

Fig. 6: Blower Switch Terminal ID (Pickup, Ram-50)

Courtesy of Mitsubishi Motor Sales of America.

Fig. 7: Front Blower Switch Terminal ID (Colt Vista & Montero)

Courtesy of Mitsubishi Motor Sales of America.

DUAL PRESSURE SWITCH

Montero, Pickup & Ram-50

1) Turn engine off. Disconnect harness connector at dual

pressure switch (located near condenser). Jumper harness connector.

Turn A/C switch and blower switch to ON positions. Momentarily turn

ignition on and listen for compressor clutch engagement.

2) If compressor clutch does not engage, check evaporator

thermistor and engine coolant temperature switch. Check for a faulty

fuse. Repair or replace components as necessary. If compressor clutch

engages, go to next step.

3) Connect manifold gauge set to system, and check operating

pressures. Dual pressure switch should allow compressor operation if

system pressure is 30-384 psi (2-27 kg/cm

). If dual pressure switch

does not operate within specified pressure range, discharge system

using approved refrigerant recovery/recycling equipment, and replace

switch.

4) After replacing switch, recharge system, and monitor

pressures for proper compressor operation. If dual pressure switch

cuts power to compressor clutch while driving even though temperatures

inside have not yet decreased, high pressure side of dual pressure

switch has possibly been activated. Go to next step.

5) Discharge system using approved refrigerant

recovery/recycling equipment. Replace switch, and recharge system.

Ensure compressor clutch operates within 30-384 psi (2-27 kg/cm

).

Check for sufficient system cooling.

ENGINE COOLANT TEMPERATURE SWITCH

1) Turn engine off. Disconnect connector at engine coolant

temperature switch. Jumper wires on harness side of connector. If

vehicle uses a single connector, ground connector.

2) Press A/C switch to ON position and turn blower switch to

ON position. Momentarily turn ignition on and listen for compressor

clutch engagement. Clutch should engage. If clutch does not engage,

check fuse and other components wired in series with compressor

clutch.

EVAPORATOR THERMISTOR

Disconnect connector and remove thermo relay from evaporator

core. Jumper wires on harness side connector. Turn A/C switch to ON

position and turn on blower. Momentarily turn ignition on and listen

for compressor clutch engagement. If clutch does not engage, check

fuse and other components wired in series with compressor clutch.

HIGH PRESSURE SWITCH

Colt Vista

Disconnect high pressure switch connector. Jumper wires on

harness side of connector. Momentarily turn ignition on and listen for

compressor clutch engagement. If clutch does not engage, check fuse

and other components wired in series with compressor clutch.

HIGH/LOW PRESSURE CUT-OFF SWITCH

Pickup & Ram-50

1) Turn engine off. Disconnect High/Low Pressure Cut-Off

(HLPCO) switch, located on refrigerant line near condenser. Jumper

HLPCO wiring harness connector. Turn A/C switch and blower switch to

ON positions. Momentarily turn ignition on and listen for compressor

clutch engagement.

2) If compressor clutch does not engage, check evaporator

thermistor and engine coolant temperature switch. Check for a faulty

fuse. Repair or replace as necessary. If compressor clutch engages, go

to next step.

3) Connect manifold gauge set to system, and check operating

pressures. HLPCO switch should allow compressor operation if system

pressure is 28-385 psi (1.9-27 kg/cm

). If HLPCO switch does not

operate within specified pressure range, discharge system using

approved refrigerant recovery/recycling equipment, and replace switch.

4) After replacing switch, recharge system, and monitor

pressures for proper compressor function. If HLPCO switch cuts power

to compressor clutch while driving even though temperatures inside

have not yet decreased, high pressure side of new HLPCO switch has

possibly been activated. Go to next step.

5) Discharge system using approved refrigerant

recovery/recycling equipment. Replace switch, and recharge system.

Ensure compressor clutch operates within 28-385 psi (1.9-27 kg/cm

).

Check for sufficient system cooling.

LOW PRESSURE SWITCH

Colt Vista

Disconnect low pressure switch connector. Jumper wires on

harness side of connector. Momentarily turn ignition on and listen for

compressor clutch engagement. If clutch does not engage, check fuse

and other components wired in series with compressor clutch.

COMPRESSOR CLUTCH

Disconnect wiring to compressor clutch. Connect battery

voltage directly to A/C compressor clutch wiring harness connector

terminals. If a click is heard, clutch engagement is okay. If click is

not heard, pulley and armature are not making contact. Repair or

replace as necessary.

REAR BLOWER SWITCH

Montero

With blower switch in position indicated in REAR BLOWER

SWITCH CONTINUITY TEST table, ensure continuity exists between

terminals listed. See Fig. 8.

REAR BLOWER SWITCH CONTINUITY TEST TABLE

Switch Terminal

Position Numbers Continuity

OFF . . . . . 1-6 . . . . . No

Low . . . .. 1, 2 & 6 . . . .. Yes

Medium 1 . . . 1, 3 & 6 . . . .. Yes

Medium 2 . . . 1, 4 & 6 . . . .. Yes

High . . . . 1, 5 & 6 . . . .. Yes

Fig. 8: Identifying Rear Blower Switch Terminals (Montero)

Courtesy of Mitsubishi Motor Sales of America.

REFRIGERANT TEMPERATURE SENSOR

Disconnect refrigerant temperature sensor electrical

connector. Using an ohmmeter, measure resistance between terminals. At