1991 MITSUBISHI 3000GT engine

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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55-4 HEATER, AIR CONDITIONER AND VENTILATION -Specifications / Special Tools
LUBRICANTSM55CD. _
ItemsSpecified lubricants
Each connection of refrigerant lineFREOL S-83 or
SUNISO 5GS
Quantity
As required
SEALANT AND ADHESIVEM55CE- -
IItemsSpecified sealant and adhesiveI
Engine coolant temperature switch threaded part3M Nut Locking Part No. 4171 or equivalent
SPECIAL TOOLSMSSDA- -
multi-use tester)
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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.
v):
I
I
I
I
\,
3’
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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HEATERS AND MANUAL AIR CONDITIONER - Service AdWment proceres 55-13. .
Charginglose
\Adaptor valve
Vacuum meter
T-joint
20M0121
(1O)Start the engine.(1l)Operate the air conditioner and set at the lowest tempera-
ture (MAX. COOL).
(12)Fix the engine speed at 1,500 rpm.
(13)Tighten the low pressure side adaptor valve and open the
service valve to charge specified amount of refrigerant.
Caution
If the service can is inverted, liquid refrigerant may bedrawn into the compressor damaging it by liquid
compression. Keep the service can upright to ensurethat refrigerant is charged in gas state.
(14)Upon completion of charging, turn back the low pressure
side adaptor valve handle all the way and close the service
valve.
CHARGING WITH REFRIGERANT RECOVERY AND RE-
CYCLING UNITWhen using refrigerant recovery and recycling unit, follow
carefully the instruction manual for the unit.
REMOVAL OF CHARGE EQUIPMENT(1) Close the charge
valve:(2) Remove the adaptor valve from each service valve.
(3) Remove the vacuum pump.
CautionDo not remove the service can, T-joints and adaptor
valves but keep them connected for next charge
operation.
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CautionRefrigerantR-l 2iAdaptorNever use the high pressure side as this may cause
/valve
refrigerant to flow back, using rupture of the servicecan.(7) Start the engine. Charge valvergmg hose
55-14 HEATERS AND MANUAL AIR CONDITIONER - Service Adjustment procedures
CORRECTING LOW REFRIGERANT LEVEL
(I) Install the charge valve to the service can with its handle
turned back all the way.
(2) Connect the charging hose to the charge valve.
(3) Connect the adaptor valve to the charging hose with itsL&lhandle turned back all the way.
(4) Tighten the charge valve handle to puncture the can.
(5) Operate the adaptor valve handle to bleed air.
(6) Install the adaptor valve to the low pressure side service
valve.
(8) Operate the air conditioner and set at the lowest tempera-
ture (MAX. COOL).
(9) Fix the engine speed at 1,500 rpm.
(10)Open the adaptor valve and charge refrigerant checking
level with the sight glass.
(1 l)Upon completion of charging, close the adaptor valve and
20M0128charge valve.
(12)Remove the adaptor valve from the service valve.
NOTEIf the service can is not emptied completely, keep the
charge valve and adaptor valve connected to the can for
next charging.
Adaptor
valve
\
DISCHARGING SYSTEMUse the refrigerant recovery unit to discharge refrigerant gas
from the system.
NOTERefer to that Refrigerant Recovery and Recycling Unit Instruc-
tion Manual for operation of the unit.
REFILLING OF OIL IN THE AIR CONDITIONER SYSTEM
Too little oil will provide inadequate compressor lubrication and
cause a compressor failure. Too much oil will ,increase
discharge air temperature.
When a
FX-105VS compressor is installed at the factory, it
contains
160 cc (9.8 cu.in.) of refrigerant oil. While the air
conditioning system is in operation, the oil is carried through
the entire system by the refrigerant.
Some of this oil will be trapped and retained in various parts of
the system.
When the following system components are charged, it is
necessary to add oil to the system to replace the oil being
removed with the component.
Condenser: 8 cc
(5 cu.in.)Evaporator: 72 cc (4.4
cu.in.)Piping: 9.6 cc
(6 cu.in.)Receiver drier: 6.4 cc
(.4 cu.in.)
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