1991 MITSUBISHI 3000GT check engine light

SUPPLEMENTAL RESTRAINT SYSTEM (SRS) - Z~-%Z%&Z% 528-49Manufacture
date
IVEHICLE TYPE: PASSENGER CAR
MU9001/
OOFOOOlSRS
warnmq light- -SDU’
t>19FOlO:SRS MAINTENANCE AND
POST-COLLISION DIAGNOSIS
M52PCAAMAINTENANCE
The SRS must be inspected by an authorized dealer
10 years
after the car manufacture date shown on the certification label
located on left front door latch post.
Maintenance Items
1.“SRS” WARNING LIGHT CHECK
When the ignition key is turned to “ON” or engine started,
the “SRS” warning light will illuminate for about 7 seconds
and then turn off.
This means that the system is functioning properly.
2. SRS COMPONENTS VISUAL CHECK
(1) Turn the ignition key to the “LOCK” position, discon-
nect the negative battery cable and tape the terminal.
CautionWait at least 30 seconds after disconnecting the
battery cable before doing any further work. The
SRS system is designed to retain enough voltage todeploy the air bag for a short time even after the
battery has been disconnected, so serious injury
may result from unintended air bag deployment
if
work is done on the SRS system immediately afterthe battery cable is disconnected.
(2) Remove the rear console assembly. (Refer to GROUP
52A
- Floor Console.)
(3) Use a screwdriver to push in the lock spring of the lock
lever of the SRS diagnosis unit to unlock the lock lever.
CautionA double-lock mechanism is employed for the
connector of the SRS diagnosis unit, so care must
be taken not to damage it by using excessive forceor by not disconnecting it correctly.
(4) Disconnect the red
14-pin connector from the SRS
diagnosis unit while pressing down the lock of the
connector. (Refer to
P.52B-9.)
13R0721113R0722
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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.

L/
i
HEATERS AND MANUAL AIR CONDITIONER -Service Adjustment Procedures 55 15
PERFORMANCE TESTM55FWAH
(I) Park the tested vehicle at the area which is not exposed to
the direct sunlight.
(2) Connect a tachometer.
(3) Turn back the adaptor valve handle all the way and install
the adaptor valves to the high pressure and low pressure
service valves.
(4) Connect the gauge manifold to the adaptor valves.
(5) Tighten the adaptor valve handle and open the service
valves.
(6) Start the engine.
(7) Set the controls to the air conditioner as follows:
Air conditioning switch: Air conditioner
- ON position
Mode selection: Face position
Temperature control: MAX. COOL position
Air selection: Recirculation position
Blower switch: HI (Fast) position
(8) Adjust engine speed to 1,000 rpm with air conditioner
clutch engaged.
(9) Engine should be warmed up with doors, windows close,
and hood open.
(1O)lnsert a thermometer in the center air conditioner outlet and
operate the engine for 20 minutes.
(II )Note the discharge air temperature.
NOTEIf the clutch cycles, take the reading before the clutch
disengages.
Performance Temperature ChartGarage
amb;in,L;am-perature21 (70)
26.7 (80)32.2 (90)37.8 (100)43.3 (110)
Iperature Dischargeair "C tem- ("F)(32.0 0.0- -3.0 37.4)(33.8 1.0- -4.0 39.2)(33.8 1.0- -4.0 39.2)(33.8 1.0- -4.0 39.2)(35.6 2.0- -41.0) 5.0
ICompressor pressure kPa discharge (psi)(98.1 690- -105.3) 740(110.9 780- -830 118.1)(123.7 870- -920 130.9)(153.6 1,080- -1,130 160.7)(172.1 1,210- -1,260 179.2)Compressor suction130
-190130-190130-190130-190130-190
pressure kPa (psi)(18.5-27.5)(18.5-27.5)(18.5-27.5)(18.5-27.5)(18.5-27.5)
REFRIGERANT LEAK REPAIR PROCEDUREM55FHAQ
LOST CHARGEIf the system has lost all charge due to a leak:
(1) Evacuate the system. (See procedure.)
(2) Charge the system with approximately one pound of
refrigerant.
(3) Check for leaks.
(4) Discharge the system.
(5) Repair leaks.
(6) Replace receiver drier.
Caution
Replacement filter-drier units must be sealed while instorage. The drier used in these units will saturate
water quickly upon exposure to the atmosphere. When
installing a drier, have all tools and supplies ready forquick reassembly to avoid keeping the system open
any longer than necessary.(7) Evacuate and charge the system.
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HEATERS AND MANUAL AIR CbNDlTlONER -Service Adjustment Procedures 55 17
ADJUSTMENT PROCEDURES(1) Select a quiet area for testing. Duplicate conditions as much
as possible. Switch compressor on and off several times to
clearly identify compressor noise.
To duplicate high ambient conditions (high head pressure),
restrict air flow through condenser. Install manifold gauge
set to make sure discharge pressure doesn’t exceed 2,070
kPa (300 psi).
(2) Tighten all compressor mounting bolts, clutch mounting
bolt, and compressor drive belt. Check to assure clutch coil
is tight (no rotation or wobble).
(3) Check refrigerant hoses for rubbing or interference that can
cause unusual noises.
(4) Check refrigerant charge. (See “Charging System”.)
(5) Recheck compressor noise as in Step 1.
(6) If noise still exists, loosen compressor mounting bolts and
retorque. Repeat Step 1.
(7) If noise continues, replace compressor and repeat Step 1.
POWER RELAY CHECKMBBFNAK(1) Remove the radiator fan motor relays (HI) and (LO) from the
relay box on the right of the engine compartment.
(2) Remove the radiator fan motor relay (air conditioner),
condenser fan motor relays (HI) and (LO), and
air-conditioner compressor relay from the relay box on the left
of the engine compartment.
(3) Remove the blower motor relay from the junction box.
(4) Remove the blower motor HI relay from the blower case
assembly.
(5) Check the continuity between terminals using a circuit
tester.
J Blower m.otor HI relay\2OFOO6l
IDLE-UP OPERATION CHECKM55FOAB
(1) Before inspection and adjustment set vehicle in the
following condition:
lEngine coolant temperature: 80 - 95°C (176 - 203°F)
lLights, electric cooling fan and accessories: Set to OFF
l Transaxle: Neutral (N or P for vehicles with
A/T)l Steering wheel: Straightforward
(2) Check to be sure that the idling speed becomes the
standard value when the air conditioner switch is switched
ON and the air conditioner is activated.
Standard value: 900
+ 100 rpm
NOTEThere is no necessity to make an adjustment, because the
idling speed is automatically adjusted by the ISC” system.
If, however, there occurs a deviation from the standard
value for some reason, check the ISC” system.
ISC: Idle Speed Control
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