A/C SWITCH
When turned on, the A/C system will operate if blower motor
control lever is in a position other than OFF. When activated, A/C
switch allows A/C compressor clutch to engage and operate the
compressor.
A/C ENGINE COOLANT TEMPERATURE SWITCH
The A/C engine coolant temperature switch, located on
thermostat housing, is wired in series with compressor clutch. When
coolant temperature is greater than switch control temperature, power
to compressor is cut and compressor is turned off until temperature
returns to operating range. Switch will turn on at 226
F (108C) and
off at 235-243F (112-118C).
AIR SELECTOR LEVER
The lever moves horizontally to select source of air used
inside passenger compartment. Lever moves from position on left
(outside air mode) to position on right (recirculated air mode). Lev\
er
should be set in recirculated air mode for maximum A/C cooling.
BLOWER MOTOR CONTROL SWITCH
Blower motor control switch rotates to select blower motor
speeds. As switch is rotated from left or OFF position, increasing
speeds of blower operation are selected. In order for A/C system to
operate, blower motor control switch must be in a position other than
OFF.
MODE SELECTOR KNOB
Mode selector knob has six modes available to achieve desired
distribution of air from various outlets. When knob is rotated fully
to left (counterclockwise), airflow is directed to upper passenger
area. In second position (clockwise), airflow is directed to upper
passenger area and slightly to leg area. Position 3, directs air
mostly to leg area and slightly to upper passenger area. Position 4,
directs air exclusively to leg area. Position 5, directs air to leg
area and to windshield and door windows. Position 6, directs air
exclusively to windshield and door windows.
TEMPERATURE CONTROL KNOB
Temperature control knob operates blend-air door in
heater/air conditioning unit, mixing cooled and heated air so that
selected air temperature can be obtained. The system will provide
cooled air when A/C switch is in ON position and blower motor is in
any position other than OFF. Temperature control knob should be on far
left (maximum cooling) side of temperature selection scale when
maximum A/C cooling is desired.
DUAL-PRESSURE SWITCH
The dual-pressure switch, mounted on receiver-drier, is wired
in series with compressor clutch. Whenever system pressures drop below
or increase above control points of switch, power supplied to
compressor will be cut and compressor function will cease until
pressures are back to normal operating ranges.
settings.
2) Set blower/fan on high speed. Close doors and windows.
Insert thermometer in center vent. Operate system for 20 minutes to
allow system to stabilize. Measure temperature.
3) Discharge air temperature must be 37-44
F (3-7C) at
center vent, with high side and low side pressures within
specification. See A/C SYSTEM SPECIFICATIONS table at beginning of
article.
A/C CONTROL UNIT (ACCU)
1) Locate A/C Control Unit (ACCU) on top of evaporator case
and disconnect 10-pin connector. Inspect connector and wiring for
damage. Turn ignition and A/C on. Set temperature control to maximum
cooling and blower switch to high. Using a DVOM set to appropriate
test function, inspect harness side of connector. See Fig. 3. Go to
next step. If all test readings are as specified, replace ACCU.
2) Terminal No. 1 (Green/Yellow wire) is ACCU output. With
A/C and blower motor on, battery voltage should be present when ACCU
has received signals from pressure and temperature sensors confirming
A/C operation is okay.
3) Terminal No. 3 (Green/Blue wire) is ACCU power supply whe\
n
A/C switch is in A/C mode. With ignition and blower on, and A/C switch
at second level setting, battery voltage should be present.
4) Terminal No. 5 (Green/Red wire) is ACCU power supply when\
A/C switch is in ECONO mode. With ignition and blower on, and A/C
switch at first level setting, battery voltage should be present.
Terminals No. 2 and 7 (Black wire) are ACCU grounds. There should be
zero volts at all times.
5) Turn ignition off. Reconnect 10-pin connector. Turn
ignition on. Turn A/C on. Set temperature control to maximum cooling
and blower switch to high. Backprobe 10-pin connector. Go to next
step. If all test readings are as specified, replace ACCU.
6) Terminal No. 10 (Blue/White wire) is air thermosensor
power supply. With ignition, blower and A/C on, approximately 5.5
volts should be present.
7) Terminal No. 8 (Blue/Yellow wire) is air thermosensor
signal. When temperature of evaporator outlet portion is 77
F (25C),
there should be approximately 3.6 volts present.
8) Terminal No. 4 (White/Blue wire) is air inlet sensor powe\
r
supply. With ignition, blower and A/C on, approximately 5.5 volts
should be present.
9) Terminal No. 9 (Yellow/Green wire) is air inlet sensor
signal. When temperature of evaporator outlet portion is 77
F (25C),
there should be approximately 1.5 volts present.
Fig. 1: Testing ACCU
Courtesy of Mitsubishi Motor Sales of America.
A/C SWITCH
Tool Name Tool Number
For Component Replacement
Steering Wheel Puller ......................... MB990803
For Testing SRS
Digital Volt-Ohm Meter (DVOM) ...................... (1)
Multi-Use Tester II ........................... MB991502
ROM Pack ........................................... ( 2)
SRS Check Harness ............................. MB991613
For Deploying Air Bags
SRS Air Bag Adapter Harness "A" ( 3) ........... MB686560
SRS Air Bag Adapter Harness "B" ( 4) ........... MB628919
( 1) - Maximum current output of DVOM must not exceed 2 mA
(milliamps) when set on minimum range of resistance
measurement.
( 2) - ROM pack is used with multi-use tester.
( 3) - For on-vehicle deployment of driver-side air bag. For
on-vehicle or off-vehicle deployment of passenger-side
air bag.
( 4) - For off-vehicle deployment of driver-side air bag.
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DISABLING & ACTIVATING AIR BAG SYSTEM
WARNING: SRS system voltage is maintained for about 60 seconds after
battery cable is disconnected. After disconnecting battery
cable, wait at least 60 seconds before servicing SRS.
Failure to wait may cause accidental air bag deployment and
possible personal injury.
To disable system, turn ignition switch to LOCK position.
Disconnect negative battery cable. Shield cable end. Wait at least 60
seconds before servicing. To activate system, reconnect negative
battery cable.
DISPOSAL PROCEDURES
WARNING: Undeployed air bag must be deployed before disposal.
Disposing of an undeployed air bag may violate federal,
state and/or local laws. This also applies to vehicles that
are to be scrapped. Never sell a used air bag module.
UNDEPLOYED AIR BAG
WARNING: Deploy air bag outdoors and away from people. Air bag
deployment makes a loud noise. NEVER deploy air bag module
with trim cover face down.
NOTE: If replacing a deployed air bag, both front impact sensors
and SRS-ECU must also be replaced. If vehicle is to be
scrapped, perform PROCEDURE 1 (ON-VEHICLE DEPLOYMENT) below.
If vehicle will continue to be operated, perform PROCEDURE 2
(OFF-VEHICLE DEPLOYMENT) below.
Procedure 1 (On-Vehicle Deployment)
1) Before proceeding, follow air bag service precautions. See
SERVICE PRECAUTIONS . Open all doors and windows. Move vehicle to an
isolated area. Disconnect negative battery cable and wrap tape around
cable terminal.
2) Disconnect positive battery cable. Remove battery. Wait at
DEFOGGER - REAR WINDOW
1998 Mitsubishi Montero
1998 ACCESSORIES & EQUIPMENT
Mitsubishi - Rear Window Defoggers
Diamante, Eclipse, Galant, Mirage, Montero, Montero Sport,
3000GT
DESCRIPTION & OPERATION
Rear window defogger is a heating filament grid bonded to
inside of window. Rear window defogger is controlled by defogger
switch on instrument panel and a defogger relay.
On Montero, a timer relay controls defogger operation for 9-
11 minutes, then turns defogger off. On Eclipse and Galant, defogger
timer circuit is integral with Electronic Timer Alarm Control System
(ETACS) ECU. Timer will operate defogger for 11 minutes then turn off,\
even with defogger switch in ON position and indicator light
illuminated. On Diamante, timer will operate defogger for 20 minutes,
then turn off.
COMPONENT LOCATIONS
COMPONENT LOCATIONS TABLE \
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Component Location
A/C ECU
Diamante ......................... Behind Center Of Dash
Data Link Connector (DLC) ....... Under Left Side Of Dash,
Near Steering Column
Defogger Relay
Montero Sport ....................... Under Left Side Of
Glove Compartment
Except Montero Sport ................... On Relay Block,
Behind Left Side Of Dash
Defogger Timer
Diamante ......................... Integral With A/C ECU
Eclipse & Galant ............... Integral With ETACS-ECU
Montero ...................... Behind Left Side Of Dash,
Behind Speaker
ETACS-ECU ......................... Above Left Kick Panel,
On Junction Block
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TROUBLE SHOOTING
* PLEASE READ THIS FIRST *
NOTE: For additional trouble shooting information on Eclipse and
Galant, see SYMPTOM TESTS.
DEFOGGER DOES NOT WORK
Check for blown fuse, poor contact, defective defogger
switch, poor connection or open wire.
DEFOGGER TIMER INOPERATIVE
NOTE: Remove window defogger switch and disconnect switch
connector for the following test.
Diamante
Rear window defogger is integral with and controlled by A/C
system ECU. To diagnose system, refer to AIR CONDITIONING & HEATING
SERVICE & REPAIR article.
Eclipse
Turn defogger switch to OFF position. Using ohmmeter, check
switch continuity. Continuity should be present between terminals No.
1 and 3, and terminals No. 2 and 6. Turn defogger switch to ON
position. Continuity should be present between terminals No. 1, 3 and
4, and between terminals No. 2 and 6. See Fig. 5. If continuity is not
as specified, replace switch.
Galant
Turn defogger switch to OFF position. Using ohmmeter, check
switch continuity. Continuity should be present between terminals No.
1 and 3. Turn defogger switch to ON position. Continuity should exist
between terminals No. 2, 4 and 6, and between terminals No. 1 and 3.
See Fig. 5 . If continuity is not as specified, replace switch.
Mirage
Turn defogger switch to OFF position. Using ohmmeter, check
switch continuity. Continuity should be present between terminals No.
1 and 3, and terminals No. 2 and 6. Turn defogger switch to ON
position. Continuity should exist between terminals No. 1 and 3, and
terminals No. 2, 4, 5 and 6. See Fig. 5. If continuity is not as
specified, replace switch.
Montero
Turn defogger switch to OFF position. Using ohmmeter, check
switch continuity. Continuity should be present between terminals No.
1 and 3, and terminals No. 4 and 5. Turn defogger switch to ON
position. Continuity should exist between terminals No. 1 and 3,
terminals No. 4 and 5, and between terminals No. 2 and 6. See Fig. 5.
If continuity is not as specified, replace switch.
Montero Sport
Turn defogger switch to OFF position. Using ohmmeter, check
switch continuity. Continuity should be present between terminals No.
1 and 5, and terminals No. 2 and 6. Turn defogger switch to ON
position. Continuity should be present between terminals No. 3 and 4,
terminals No. 1 and 5, and between terminals No. 2 and 6. See Fig. 5.
If continuity is not as specified, replace switch.
3000GT
1) Remove defogger switch assembly from instrument cluster
bezel. With defogger switch in OFF position, check switch continuity
using ohmmeter.
2) Continuity should exist between terminals No. 3 and 4.
With defogger switch in ON position, continuity should exist between
terminals No. 1 and 2, terminals No. 1 and 6, and between terminals
No. 3 and 4. See Fig. 6. If continuity is not as specified, replace
switch.
Fig. 5: Identifying Defogger Switch Terminals (Eclipse, Galant,
Mirage, Montero & Montero Sport)
Courtesy of Mitsubishi Motor Sales of America
At heater unit, remove center air outlet cool air by-pass
lever cable from damper lever. To remove center air outlet, push
springs at bottom of center air outlet upward. Outlet is located above
radio. Remove switch from center air outlet. To install, reverse
removal procedure. Turn cool air by-pass lever on outlet fully upward.
Pull air by-pass lever fully downward and install cool air by-pass
lever cable to damper lever.
Removal & Installation (Mirage)
Remove driver-side lower dash panel. Remove center console
assembly and foot distribution duct. Disconnect rear window defogger
switch harness connector. Remove switch. To install, reverse removal
procedure.
Removal & Installation (Montero)
Remove defogger switch by prying switch off instrument
cluster bezel. Disconnect wiring harness from defogger switch. Remove
switch. To install, reverse removal procedure.
Removal & Installation (Montero Sport)
Remove instrument cluster bezel. Bezel is held in by metal
clips. Disconnect wiring harness from defogger switch. Remove switch
from behind bezel. To install, reverse removal procedure.
Removal & Installation (3000GT)
Remove knee protector. Remove steering column upper and lower
covers. Remove instrument cluster bezel. Disconnect wiring harness
from defogger switch. Remove defogger switch. To install, reverse
removal procedure.
WIRING DIAGRAMS
Fig. 9: Rear Window & Mirror Defogger System Wiring Diagram
(Diamante)
Fig. 10: Rear Window Defogger System Wiring Diagram (Eclipse)