1991 MITSUBISHI 3000GT belt

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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55-20 HEATERS AND MANUAL AIR CONDlTlONER - Resistor, Belt Lock Controller
RESISTOR, BELT LOCK CONTROLLERM55JA- -
REMOVAL AND INSTALLATION
viRemoval steps
1. Stoooer
2OFOO732. Globk box outer case assembly
3. Resistor
4. Under cover
5. Belt lock controller
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INSPECTION
RESISTOR CHECK
hl55JCADUsing a circuit tester, measure the resistance between the
terminals indicated below.
The condition can be considered satisfactory if the value
measured at this time is equivalent to the standard value.
Standard value
Terminals measuredStandard value fi
Between terminals a-- @Approx. 1.79 - 2.06
Between terminals
@ -@Approx. 1 .I 0 - 1.26
Between terminals @ - @Approx. 0.38 - 0.44vision

HEATERS AND MANUAL AIR CONDITIONER - Compressor55-27
COMPRESSOR
M55SA- -
/REMOVAL AND INSTALLATION
iJ
iPre-removal Operation
l Discharge of the Refrigerant(Refer to P.55-14.)9.0 Nm
7.Oft.lbs.
\Post-installation Operation
l Adjustment of the Compressor
Drive Belt (Refer to GROUP 11 -Service Adjustment Procedures.)l Charging of Refrigerant(Refer to P.55-11.)21 Nm
15 ftlbs.Removal steps
a*1. Compressor drive belt
2. Condenser fan motor assembly
4*3. Connection of suction hose and discharge
41) l +4. !%znator (Refer to GROUP l6-Alternator.)*I) l * 5. Compressor
6. Idler pulley
7. Compressor bracket
!I zorr-rion pulley assembly;
;: Fontsion pulley
12. Adjustment plate
13. Tension pulley bracket6
45 Nm
33 ft.lbs.
52ONOO89Compressor oil:
Freol S-83 or Suniso 5GS
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55-28HEATERS AND MANUAL AIR CONDITIONER - Comtxessor
20F0067
SERVICE POINTS OF REMOVALM55SBAE1. REMOVAL OF COMPRESSOR DRIVE BELT
(1) Loosen bolt “A” for holding the tension pulley.
(2) Loosen bolt “B” for adjustment, and remove the
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compressor drive belt.
3.REMOVAL OF SUCTION HOSE AND DISCHARGE HOSE
If the hoses are disconnected, cap the hoses with a blankplug to prevent entry of dust, dirt, and water.
5. REMOVAL OF COMPRESSOR
Caution
Lay the towel on the brake tube to protect them. When
install the compressor, do not damage the brake tubes.
This work must be done carefully so as not to spill the
compressor oil.
INSPECTIONM55SCAEl Checking for heat damage of the tension pulley.
l
Check for excessive play or deflection of the tension pulley.l Check for unusual wear of the tension pulley.
l Check for hardening of the air conditioner belt.
lCheck for unusual wear or abrasion of the air conditioner ,
belt.
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OPERATION CHECK OF THE COMPRESSOR’S MAGNETIC
CLUTCH
(1) Connect terminal @ at the compressor side to the positive
(+) terminal of the battery, and ground the negative (-)terminal of the battery to the compressor.
(2) The condition of the compressor’s magnetic clutch can beconsidered satisfactory if the operation sound (a “click”
sound) of the magnetic clutch can be heard when this
check is made.
SERVICE POINTS OF INSTALLATIONM55SDAF5. INSTALLATION OF COMPRESSOR
If a new compressor is installed, first adjust the amount of
oil according to the procedures described below, and then
install the compressor.(1) Measure the amount (X cc) of oil within the removed
compressor.
(2) Wipe away (from the new compressor) the amount ofoil calculated according to the following formula, and
then install the new compressor.
New compressor oil amount
160 cc (9.8 cu.in.) - X cc= Y cc
NOTE
Y cc indicates the amount of oil in the refrigerant line,l/jthe condenser, the cooling unit, etc.
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55-36 HEATERS AND MANUAL AIR CONDITIONER -Ventilators (Instrument Panel)
VENTILATORS (INSTRUMENT PANEL)M55YA- -
REMOVAL AND INSTALLATION
-16
/‘4
Removal steps
l * +a1. Knee protector
(Refer to GROUP 52A-Instrument Panel.)
2. Foot shower duct
3. Lap cooler duct
4. Under cover
5. Belt lock controller
6. Side defroster hoses A
7. Duct (Vehicles without air conditioner)
** l +8. instrument panel (Refer to GROUP 52A-instrument Panel.)
9. Center duct
10. Air duct (right side)
11. Air duct (left side)12. Distribution duct (center)
13.Defroster duct14. Side defroster hoses B
15. Defroster garnishes
16.Photo sensor17. Center air outlet assembly
18. Side air outlet assembly
19. Distribution duct (foot)2OFOO55
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FULL AUTO AIR CONDITIONER - Troubleshooting55-495. Inspection of belt lock controller circuit
Compressor relay
tAir conditioner control unitAir conditioner
+control panelAir
condltloner,c.compressor commandAH condmonerarithmetic
circuitcompressor ONstgnal
ComparatorAir condltlonercompressor ON signal20 FOO58
Revolution pickup sensor
LiTroubleshooting Hintsl Air conditioner control unit terminal voltages
Terminal No.
Signal nameConditionTerminal voltage
11Air conditioner outputCompressor ONIO V to battery voltage
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FULL AUTO AIR CONDITIONER -Power Transistor, Belt Lock Controller55-57
POWER TRANSISTOR, BELT LOCK CONTROLLER
REMOVAL AND INSTALLATION
J?nPower transistor removal steps
1. Stopper
2. Glove box outer case assembly
3. Power transistor
2OFOO73Belt lock controller removal steps
M55LA- -
4. Under cover
5. Belt lock controller
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