service MITSUBISHI 3000GT 1991 Service Manual

Air Bag ModuleSUPPLEMENTAL RESTRAINT SYSTEM (SRS) - and Clock Spring526-6319FOlll
3
SERVICE POINTS OF REMOVAL1. DISCONNECTION OF THE NEGATIVE (-) BATTERY
CABLE FROM THE BATTERYTurn the ignition key to the “LOCK” position, disconnect
the negative battery cable and tape the terminal.
Caution
Wait at least 30 seconds after disconnecting the battery
cable before doing any further work. The SRS system is
designed to retain enough voltage to deploy the air bagfor a short time even after the battery has been
disconnected, so serious injury may result from unin-
tended air bag deployment if work is done on the SRSsystem immediately after the battery cable is discon-
nected.2. REMOVAL OF AIR BAG MODULE
(1) Remove the air bag module mounting nut using a
socket wrench from the back side.
(2) When disconnecting the connector of the clock spring
from the air bag module, press the air bag’s lock toward
the outer side to spread it open. Use a screwdriver, as
shown in the figure at the left, to pry so as to remove
the connector gently.
CautionWhen disconnecting the air bag module-clock
spring connector, take care not to apply excessiveforce to it.
(3) The removed air bag module should be stored in a
clean, dry place with the pad cover face up.
8. REMOVAL OF STEERING WHEEL
Remove the steering wheel by using a steering wheel
puller.
CautionDo not hammer on the steering wheel. Doing so may
damage the collapsible column mechanism.
9. DISCONNECTION OF THE SRS DIAGNOSIS UNIT AND
CLOCK SPRING CONNECTION
(1) Remove the rear console assembly.
(Refer to GROUP 52A
- Floor Console.)
(2) Use a screwdriver to push in the lock spring of the lock
lever of the SRS diagnosis unit to unlock the lock lever.
Caution
A double-lock mechanism is employed for the connec-
tor of the SRS diagnosis unit, so care must be taken notto damage it by using excessive force or by not
disconnecting it correctly.
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52B-66Air Bag ModuleSUPPLEMENTAL RESTRAINT SYSTEM (SRS) - and Clock SpringMB991349
SRS CHeck Harness
No.7 connectcNo. 2 connector
View A
SRS Check Harness connector
16R219C
19FOlO!I
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(4) Joint the No. 2 connector (air bag module side) and No. 7
connector of clock spring to connector @ and connector
@,respectively, of the SRS Check Harness.
NOTEWhen joining SRS Check Harness connector
(4) , align its
white paint with the hollow portion of the No. 2 connector
of the clock spring.
(5) Check for continuity between terminal 1 and terminal 21,
and terminal 2 and terminal 22, of SRS Check Harness
connector @ ,
using a digital multi-meter.
Standard value: less than
0.452(6) If, as result of above checks, even one abnormal point is
discovered, replace the clock spring with a new one.
SERVICE POINTS OF INSTALLATION
PRE-INSTALLATION INSPECTION
(I) Before the clock spring and air bag module are installed in
the vehicle, they must be visually inspected.
If a dent, crack or other deformation, or any rust, is
detected, discard the clock spring and/or air bag module
and replace it with a new one that passes the visual
inspection.
CautionDispose of an air bag module only according to the
specified procedure. (Refer to
P.52B-69 to P.52B-72.)(2) Before the clock spring is installed in the vehicle, the
resistance between No. 2 and No. 7 connectors of clock
spring must be confirmed to be within standard value; less
than
0.4(2.Use the SRS Check Harness and digital multi-meter. (Refer
to “CHECKING THE CLOCK SPRING”.)
If the clock spring is not within that standard value range,
discard it and replace it with a new one that has the proper
standard value.
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Air Bag Module
SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - and Clock Spring52B-67Multi-use Testkr
ROM pack
(MB991 341)(MB991 359)
Diagnosis/
service
data
oumutGround
16LOO9'(3) Insert ROM pack into the Multi-use Tester and connect
tester to Diagnosis Check Connector in glove compart-
ment.
(4) Reconnect negative terminal of battery, and turn the
ignition key to the “ON” position.
(5) Conduct self-diagnosis using Multi-use Tester to ensure
entire SRS operates properly, except open circuit of air bag
module (“22. SQUIB TRBL 2”). (Refer to
P.52B-18.)(6) Turn the ignition key to the “LOCK” position, disconnect
the negative battery cable and tape the terminal.
Caution
Wait at least 30 seconds after disconnecting the battery
cable before doing any further work. The SRS system is
designed to retain enough voltage to deploy the air bagfor a short time even after the battery has been
disconnected, so serious injury may result from unin-
tended air bag deployment if work is done on the SRSsystem immediately after the battery cable is discon-
nected.
11. INSTALLATION OF CLOCK SPRINGAlign the mating mark and “NEUTRAL” position indicator of
the clock spring, and, after turning the front wheels to the
straight-ahead position,install the clock spring to the
column switch.
CautionIf the clock spring’s mating mark, is not properly
aligned, the steering wheel may not be completely
rotational during a turn, or the flat cable within the
clock spring may be severed, obstructing normal
operation of the SRS and possibly leading to serious
injury to the vehicle’s driver.
9. CLOCK SPRING AND SRS DIAGNOSIS UNIT CONNEC-
TIONAfter securely and correctly installing the clock spring’s
connector to the SRS diagnosis unit, be absolutely sure to
press down the lock lever of the SRS diagnosis unit.
13R072113R072;8. INSTALLATION OF STEERING WHEEL
(1) Before installing the steering wheel, be sure to first turn
the vehicle’s front wheels to the straight-ahead position
and align the mating mark and “NEUTRAL” position
indicator of the clock spring.
Caution
Be sure when installing the steering wheel, that the
harness of the clock spring does not become caughtor tangled.
(2) After clamping, turn the steering wheel all the way in
both directions to confirm that steering is normal.
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55-1
HEATER, AIR
CONDITIONER
AND VENTILATION
CONTENTSM55AA- -
HEATERS AND AIR CONDITIONING................3HEATER UNIT*........................................................................22
SPECIFICATIONS
....................................................................3REFRIGERANT LINE................................................................35General Specifications
........................................................3RESISTOR................................................................................20Lubricants
............................................................................4SAFETY PRECAUTIONS........................................................9Sealant and Adhesive............................................................4
Service Specifications3SERVICE ADJUSTMENT PROCEDURES............................10........................................................
SPECIAL TOOLS4Charging Procedures............................................................11
i
........................................................................Charging the Refrigerant....................................................12Compressor Drive Belt Adjustment....................................11
HEATERS AND MANUAL AIR CONDITIONER5Compressor Noise................................................................16
................................................16
AIR CONDITIONER SWITCH................................................21Handling Tubing andFittings
Idle-up Operation Check....................................................17
BELT LOCK CONTROLLER20Performance Test................................................................15....................................................
BLOWER ASSEMBLYPower Relay Check............................................................17............................................................23Refrigerant Leak Repair Procedure....................................15COMPRESSOR........................................................................
27TestProcedures....................................................................10
CONDENSER AND CONDENSER FAN MOTOR................33TROUBLESHOOTING............................................................5
ENGINE COOLANT TEMPERATURE SWITCH....................
39VENTILATORS (AIR INLET AND AIR OUTLET)................38
EVAPORATOR
........................................................................
25VENTILATORS (INSTRUMENT PANEL)*............................36
HEATER CONTROL ASSEMBLY*
........................................18CONTINUED ON NEXT PAGE
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
(1)A Supplemental Restraint System (SRS), which uses a driver-side air bag, has been installed in the 3000GT.(2)The SRS includes the following components: impact sensors, SRS diagnosis unit: SRS warning light, air bagmodule, clock spring, interconnecting wiring. Other SRS-related components (that may have to be
removed/installed in connection with SRS service or maintenance) are indicated in the table of contents byan asterisk (*).
WARNING!(1)Improper service or maintenance of any component of the SRS, or any SRS-related component, can lead to
personal injury or death to service personnel (from inadvertent firing of the air bag) or to the driver (fromrendering the
SRS inoperative).(2) Service or maintenance of any SRS component or SRS-related component must be performed only at anauthorized MITSUBISHI dealer.
(3) MITSUBISHI dealer personnel must thoroughly review this manual, and especially its GROUP 52B
-Supplemental Restraint System (SRS), before beginning any service or maintenance of any component of theSRS or any SRS-related component.

55-2FULL AUTO AIR CONDITIONER........................40OTHER PARTS........................................................................62
AIR-CONDITIONER CONTROL PANEL*,POWER TRANSISTOR, BELT LOCK CONTROLLER........57
AIR-CONDITIONER CONTROL UNIT*................................56
REFRIGERANT LINE................................................................62
COMPRESSOR
........................................................................62SAFETY PRECAUTlONS........................................................56
CONDENSER AND CONDENSER FAN MOTOR
................
62SENSORS....................................................................................60
DAMPER CONTROL MOTOR ASSEMBLY*........................
58SERVICE ADJUSTMENT PROCEDURES............................56
ENGINE COOLANT TEMPERATURE SWITCH
....................62
TROUBLESHOOTING............................................................40

HEATER, AIR CONDITIONER AND VENTILATION - Specifications55-3
HEATER, AIR CONDITIONER AND VENTILATION
LSPECIFICATIONSM55CA. -
/’
L;
GENERAL SPECIFICATIONS
Items
Heater unit
Type
Heater control assembly
Compressor
Model
Refrigerant unit lubricant
cc (cu.in.1
V belt sizemm (in.)
Dual pressure switch
High pressure switch
kPa (psi)
Low pressure switchkPa (psi)
Freezer prevention
“C (“F)
Refrigerant and quantityg (oz.)
Specifications
Three-way-flow full-air-mix system
Dial type
Scroll type (FX-105 VS)
FREOL S-83 or SUNISO 5GS160 & 20 (9.8 + 1.2)
1,150 (45.3)
OFF: 2,700 (384)ON: 2,100 (299)
OFF: 210 (30)
ON
: 235 (33)
Air temperature thermostatOFF: - 2 (28.4)
ON: 2 (35.6)
R-l 2Approx. 970 (34)
SERVICE SPECIFICATIONSM55CB. -
Items
Standard value
Idle speed when air conditioner onrpm
Resister resistance value1R
Refrigerant temperature sensor
Sensor-ON temperature
“C (“F)
Sensor-OFF temperature“C (“F)
Revolution pick up sensor standard resistance 0
Clutch clearancemm (in.)
Engine coolant temperature switch
Switch-OFF temperature
“C (“F)

Air mix damper potentiometer motor assembly resistanceMAX. HOT
kQMAX. COOL
kS1
Outlet selector damper potentiometer assembly resistanceDEF. position
kS1FACE position
kfl
Water temperature sensor
Sensor-ON temperature
“C (“F)
Specifications
900
f 100 CA/T at P range>
1.76
- 2.06 (Across terminals @and 0)
1 .I 0 - 1.26 (Across terminals @and 0)
0.38 - 0.44 (Across terminals @and @)
Approx. 110 (230) or less
Approx. 155 (311) or more
405
f 35 when ambient temperature is 20°C (68°F)
0.4 - 0.6 (.Ol - .02)
112-118(233-244)
0.2
4.9
2.0
4.3
26.5 f 4 (79.7 + 7)
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HEATERS AND MANUAL AIR CONDITIONER - safety Pre=utm55-9
SAFETY PRECAUTIONSR-12 refrigerant is a chlorofluoro-carbon
(CFC) that
can contribute to the depletion of the ozone layer in
the upper atmosphere.
Ozone filters out harmful radiation from the sun.
To assist in protecting the ozone layer, Mitsubishi
Motor Sales of America recommends that a R-12
refrigerant recycling device that meets SAE stan-
dard
J1991 be used.
Contact an automotive service equipment supplier
for refrigerant recycling equipment that is available
in your area.
The refrigerant used in all air conditioner is R-l 2. It is
transparent and colorless in both the liquid and
vapor state. Since it has a boiling point of
-29.8”C(-21.7”F), at atmospheric pressure, it will be a vapor
at all normal temperatures and pressures. The vapor
is heavier than air, non-flammable, and nonexplo-
sive. It is nonpoisonous except when it is in direct
contact with open flame. It is noncorrosive except
when combined with water. The following precau-
tions must be observed when handling R-12.
CautionWear safety goggles when servicing the refri-
geration system.R-12 evaporates so rapidly at normal atmospheric
pressures and temperatures that it tends to freeze
anything it contacts. For this reason, extreme care
must be taken to prevent any liquid refrigerant from
contacting the skin and especially the eyes. Always
wear safety goggles when servicing the refrigera-
tion part of the air conditioning system. Keep a
bottle of sterile mineral oil handy when working on
the refrigeration system. Should any liquid re-
frigerant get into the eyes, use a few drops of
mineral oil to wash them out. R-12 is rapidly
absorbed by the oil. Next splash the eyes with
plenty of cold water. Call your doctor immediately
even though irritation has ceased after treatment.
CautionDo not heat R-12 above 52°C
(125.6”F).
M55PAAFIn most instances, moderate heat is required to
bring the pressure of the refrigerant in its container
above the pressure of the system when charging or
adding refrigerant. A bucket or large pan of hot
water not over 52°C
(125.6”F) is all the heat required
for this purpose. Do not heat the refrigerant contain-
er with a blow torch or any other means that would
raise temperature and pressure above this tempera-
ture. Do not weld or steam clean on or near the
system components or refrigerant lines.
Caution
Keep R-12 containers upright when charging the
system.When metering R-12 into the refrigeration system,
keep the supply tank or cans in an upright position. If
the refrigerant container is on its side or upside
down, liquid refrigerant will enter the system and
damage the compressor.
CautionAlways work in a well-ventilated room.
Good ventilation is vital in the working area.
Although R-12 vapor is normally nonpoisonous,
contact with an open flame can cause the vapor to
become very poisonous. A poisonous gas is pro-
duced when using the flame-type leak detector.
Avoid inhaling the fumes from the leak detector.
CautionDo not allow liquid refrigerant to touch bright
metal.Refrigerant will tarnish bright metal and chrome
surfaces, and in combination with moisture can
severely corrode all metal surfaces.
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55-10 HEATERS AND MANUAL AIR CONDITIONER -Service Adjustment Procedures
OFF-----__-__1210235 2,1002,700
(30) (33)(299) (384)
Pressure Fil
2OPOOlL
SERVICE ADJUSTMENT PROCEDURES
M55FEAU
TEST PROCEDURESSIGHT GLASS REFRIGERANT LEVEL TEST
The sight glass is a refrigerant level indicator. To check the
refrigerant level, clean the sight glass and start the vehicle
engine. Push the air conditioner button to operate the com-
pressor, place the blower switch to high and move the
temperature control lever to MAX. COOL. After operating for a
few minutes in this manner, check the sight glass.
(I) If the sight glass is clear, the magnetic clutch is engaged,
the compressor discharge line is warm and the compressor
inlet line is cool; the system has a full charge.
(2) If the sight glass is clear, the magnetic clutch is engaged
and there is no significant temperature difference between
compressor inlet and discharge lines; the system has lost
some refrigerant.
(3) If the sight glass shows foam or bubbles, the system could
be low on charge. The system has to be charged with some
refrigerant.
MAGNETIC CLUTCH(1) Disconnect the wiring to the magnetic clutch.
(2) Connect battery (+) voltage directly to the wiring for the
magnetic clutch.
(3) If the magnetic clutch is normal, there will be a “click”. If
the pulley and armature do not make contact (“click”), there
is a malfunction.
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RECEIVER DRIERTo Test the Receiver Drier
(1) Operate the unit and check the piping temperature by
touching the receiver drier outlet and inlet.
(2) If there is a difference in the temperatures, the receiver
drier is restricted.
Replace the receiver drier.
DUAL PRESSURE SWITCH (LOW PRESSURE SWITCH)
(I) Turn back the adaptor valve handle all the way and install it
to the low pressure side service valve.
(2) With the gauge manifold low pressure service valves
closed, connect the gauge manifold high pressure side
charging hose to the adaptor valve.
(3) Tighten the adaptor valve handle and open the service
valve.
(4) If there in continuity between the dual pressure switch
terminals when the low pressure side pressure is at the
level of dual pressure switch ON condition shown to the
left, the switch is functioning normally. If not, replace the
L/(switch.
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HEATERS AND MANUAL AIR CONDITIONER -Service Adjustment Procedures 55 1 1
lr In et sensor
2oFoo57
UC03xD:c.-;am$2lYXSC0x.x
xa0:: :,:::25 cc,ii 77h>Temperature20A043F
argqse
20M012FIN-THERM0 SENSOR AND AIR-INLET SENSOR
(1) Disconnect the sensor’s connector at the evaporator case,
and by using an ohmmeter, measure the resistance.
If the resistance is within
+I 0% of value of the characteris-
tic curve, the sensor is functioning normally.
(2) If the sensor is normal, there is a malfunction of the air
conditioner control unit, and it should be replaced.
COMPRESSOR DRIVE BELT ADJUSTMENTM55FJAGRefer to GROUP 11
- Engine Adjustment.
CHARGING PROCEDURESM55FTAB
INSTALLATION OF CHARGE EQUIPMENT
(I) Turn back the adaptor valve handle all the way and install
each adaptor valve to the high and low pressure service
valves.
(2) Tighten the adaptor valve handle and open the service
valves.
(3) Connect the charge valve to the T-joint:
(4) With the charge valve handle turned back all the way, install
the service can.
(5) Connect each charge equipment as illustrated.
NOTE
(4) Do not connect the high and low pressure sides
adversely. (Connect high pressure side to the con-
denser and low pressure side to the evaporator.)
(2) The indications
“DIS” and “SUC” on the compressor
indicate high and low pressure sides respectively.
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55-12 HEATERS AND MANUAL AIR CONDITIONER - Service Adjustment Procedures
CHARGING SYSTEMAdaDtor valve
Vacuum meter20MOli
l-TSB IHold this conditron
for 5 minutes.
Gas leak check
is evident
1
/ Refrigerant charge1The refrigerant system must have been evacuated using the
previous procedure before charging.
Charge using only R-12 refrigerant. R-12 is available in bulk
tanks or small cans. Follow the safety precautions for handling
R-12 as listed in this group.
CHARGING THE REFRIGERANTCHARGING WITH SMALL CANS
Wh,en using disposable cans of this type, follow carefully the
can manufacturers instructions.
(1) Start up the vacuum pump.
Caution1. Do not use the compressor for evacuation.
2. Do not operate the compressor in the vacuum
condition; damage may occur.
(2) Evacuate to a vacuum reading of 100
kPa (89.5 psi) or
higher (approx. IO minutes).
(3) Turn back the high pressure side adaptor valve all the way
and close the service valve.
(4) Stop the vacuum pump and allow to stand for 5 minutes.
(5) Check for leaks. (Good if the vacuum is held.)
(6) Tighten the charge valve handle to puncture the service
can.(7) Open the charge valve to charge the system with re-
frigerant.
(8) When the refrigerant is no longer drawn in, turn back the
low pressure side adaptor valve handle all the way and
close the service valve.
(9)
Chack for gas leaks using a leak detector.
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