1991 MITSUBISHI ECLIPSE battery

24-6HEATERS AND AIR CONDITIONING - TroubleshootingAIR CONDITIONER CONTROL
UNIT CIRCUIT
1 Battery IBlower switch
litalAir conditioner
IAir inlet Air outlet1-isensorsensor
temperature
Corn- L Tpressor
relayI IMagnetic
AclutchMPI control*Wire harness sideDescription of Operation
(1) A negative-characteristic thermistor is employed
for the air-therm0 sensor and the air-inlet sensorin order to convert the ambient temperature at
the sensor part to resistance.
The sensor power-supply voltage
(5V) of the air
conditioner control unit is applied to each sen-
sor.
(2) The compressor operation mode changes (fromOFF to ECONO to A/C...) each time the air
conditioner switch is pressed. When the air
conditioner switch is pressed in to the first step,the mode is changed to the ECONO mode (the
indicator illuminates in orange, and the voltage
at terminal 4 of the air conditioner switch
becomes Bv.
When pressed in to the second step, the mode
is changed to the air conditioner mode (the
indicator illuminates in green), and the voltage at
terminal 2 of the air conditioner switch becomes
Bv.Bv: Battery voltage
(3) The output (terminal 4) of the air conditioner
control unit is output when all of the following
conditions are satisfied.
@ The air conditioner switch is ON (ECONO or
A/C mode).
@ The air-therm0 sensor ambient temperature
(evaporator outlet air temperature) is
4°C
(39°F) or higher.
@ The air-inlet sensor ambient temperature
(evaporator intake air temperature) is
4°C
(39°F) or higher.

24-14 HEATERS AND AIR CONDITIONING - Service Adjustment Procedures
-Discharge
w-w
SuctiongaugeDischalgauge
2OUO306
SuctiongaugeDischargegauge
2OUO307--
MAGNETIC CLUTCH(I) 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.
Using an ohmmeter, measure the resistance of the clutch
coil between the clutch lead wire and ground.
Standard resistance: 3.4-3.8
Q at 20°C (88°F)If resistance is not as specified, replace the coil.
COMPRESSOR(1) Install the manifold gauge set, and run the air conditioner.
(2) If a pressure of approx. 490 kPa (71 psi) is indicated on the
suction gauge side and a pressure of approx. 883
kPa (128
psi) is indicated on the discharge gauge side, the compres-
,“ssor has abnormal compression.
-IReplace the compressor.
(3) If a pressure of 294 to 392 kPa (43 to 57 psi) is indicated on
the suction gauge side and a pressure of approx. 1,961
kPa(284 psi) is indicated on the discharge gauge side, it is
suspected that air is present in the air conditioning system.Discharge the system, evacuate and recharge with speci-
fied amount of refrigerant.
(4) During operation of the air conditioner, cold air may stop
flowing after the elapse of time and this state is maintainedbefore cold air flows out again. If cold air stops flowing out
with negative pressure indicated on the suction gauge sideand a pressure of 588 to 980
kPa (85 to 142 psi) indicated
on the discharge gauge side, it is suspected that water is
present in the air conditioning system.
L=I
Discharge the system. Replace receiver drier. Evacuate and-check for leaks, and recharge with specified amount of
refrigerant.

24-24 HEATERS AND AIR CONDITIONING - Service Adjustment Procedures
COMPRESSOR NOISENUFIABWhen investigating an air conditioning related noise, you must
first know the conditions when the noise occurs. These
conditions are: weather, vehicle speed, in gear or neutral,
engine temperature or any other special conditions.
Noises that develop during air conditioning operation can oftenbe misleading. For example: what sounds like a failed front
bearing or connecting rod, may be caused by loose bolts, nuts,mounting brackets, or a loose clutch assembly. Verify acces-
sory drive belt tension (power steering, or alternator).
Improper accessory drive belt tension can cause a misleading
noise when the compressor is engaged and little or no noise
when the compressor is disengaged.
Drive belts are speed sensitive. That is, at different engine
speeds, and depending upon belt tension, belts can develop
unusual noises that are often mistaken for mechanical prob-
lems within the compressor.
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 coilis tight (no rotation or wobble).
(3) Check refrigerant hoses for rubbing or interference that cancause unusual noises.
(4) Check refrigerant charge (See “Charging the 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.
Condenser fan motor relay,
Magnet clutch
relay, Blower
motor High
relayHeater relayML0312
16W908
POWER RELAY CHECKNUFNAE
NOTEFor information concerning the installation position of each
relay, refer to
P.24-8.CONDENSER FAN MOTOR RELAY, MAGNET CLUTCH
RELAY, BLOWER MOTOR HIGH RELAY, HEATER RELAY
Check for continuity between the terminals when- the battery
power-supply is applied to terminal (2). and terminal (4) is
grounded.
1 When current flows 1 Between terminals l-3 1 Continuity1
I
When no currentBetween terminals l-3 No continuity
flowsBetween terminals 2-4 Continuity
IKinks in the refrigerant tubing or sharp bends in the
Never attempt to rebend formed lines to fit. Use the
refrigerant hose lines will greatly reduce the
capac-correct line for the installation you are servicing.
ity of the entire system. High pressures are
pro-A good rule for the flexible hose lines is keep the
duced in the system when it is operating. Extreme
radius of all bends at least 10 times the diameter of
care must be exercised to make sure that all
the hose.
connections are pressure tight. Dirt and moisture
Sharper bends will reduce the flow of refrigerant.
can enter the system when it is opened for repair or
The flexible hose lines should be routed so that theyreplacement of lines or components. The following
are at least 80 mm (3 in.) from the exhaust manifold.precautions must be observed.
It is good practice to inspect all flexible hose lines atThe system must be completely discharged before
least once a year to make sure they are in good
opening any fitting of connection in the refrigeration
condition and properly routed.
Fsystem. Open fittings with caution even after the
Unified plumbing connections with O-rings. These
4’system has been discharged. If any pressure is
noticed as a fitting is loosened, allow trappedO-rings are not reusable.
pressure to bleed off very slowly.

HEATERS AND AIR CONDITIONING - Service Adjustment Procedures 24-25
16A1077
20AO499
CONDENSER FAN MOTOR HIGH-LOW SELECTING RELAYCheck for continuity between the
term,inals when the battery
power-supply is applied to terminal
(5), and terminal (3) is
grounded.
IWhen current flows1 Between terminals l-2 1 Continuity1When no current
flows
IDLE-UP OPERATION CHECKN24FoAA
(I) Before inspection and adjustment set vehicle in the
following condition:
l Engine coolant temperature:
80-90°C (176-194°F)
lLights, electric cooling fan and accessories: Set to OFFl Transaxle: Neutral
(N or P for vehicles with A/T)l Steering wheel: Straightforward
(2) Check whether or not the idling speed is the standard
value.Standard value:
4.8L Engine>700 rpm
<2.0L DOHC Engine>750 rpm
NOTE
There is no necessity to make an adjustment, because theidling 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.
(3) Check to be sure that the idlig speed becomes the standardvalue when the air conditioner switch is switched ON and
the air conditioner is activated.
Standard value: 850 rpm
NOTE
There is no necessity to make an adjustment, because theidling 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

HEATERS AND AIR CONDITIONING - Blower Assemblv24-33Removal steps
1. Shower duct R.H.
2. Hose
+4 3. Blower motor assembly
l 4. Packing
--
. . . .
20A0428
5. t-an lnstallatlon nut6. Fan
NOTE(1) Reverse the removal procedures to reinstall.(2) l 4 : Refer to “Service Points of installation”.
BLOWER ASSEMBLY-- REMOVAL AND INSTALLATIONZOAO50
NUKA-
INSPECTIONN24KCAL
lCheck for bending or abnormal deflection of the rotating
shaft of the blower motor assembly.
l Check for cracking or deterioration of the packing.
l Check for damage to the fan.
l Check for damage to the blower case.
l Check the operation of the inside/outside air-selection
damper, and for damage.
BLOWER MOTOR ASSEMBLY CHECK
(1) Disconnect the blower motor terminals.
(2) Connect the blower motor terminals directly to the battery
and check that the blower motor operates smoothly.
(3) Next, reverse the polarity and check that the blower motor
operates smoothly in the reverse direction.
SERVICE POINTS OF INSTALLATIONNUKDAF4. INSTALLATION OF PACKING
If the packing is cracked, replace with a new one.
3. INSTALLATION OF BLOWER MOTOR ASSEMBLY
Before installing the blower motor assembly, carefully
clean away any dust, dirt, etc. adhering to the inner surface
of the blower case.

HEATERS AND AIR CONDITIONING - Compressor24-39
\/20A0400
20R0507OPERATION CHECK OF THE COMPRESSOR’S MAGNETIC
CLUTCH(1) Disconnect the compressor’s connector.
(2) Connect terminal
@ at the compressor side to the positive(+) terminal of the battery, and ground the negative
(-)terminal of the battery to the compressor.
(3) The condition of the compressor’s magnetic clutch can be
considered satisfactory if the operation sound (a “click”
sound) of the magnetic clutch can be heard when this
check is made.
SERVICE POINTS OF INSTALLATIONN248DADa13. 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 of
oil calculated according to the following formula, and
then install the new compressor.
New compressor oil amount 80 cc (4.9
cu.in.) - X cc =
Y cc
NOTE
Y cc indicates the amount of oil in the refrigerant line,
the condenser, the cooling unit, etc.
12. CONNECTION OF O-RING/
11. DISCHARGE HOSE/
10. SUCTION HOSE
(1) Take care that the O-rings are not caught, crushed or
cracked.(2) Since the O-ring size of suction hose is different from
that of discharge hose, be sure to connection correctly.
1t
/

24-44HEATERS AND AIR CONDITIONING - Coinpressiir
l-l12”
2OW8636. INSTALLATION OF CLUTCH CO&
The clutch coil must be aligned with the pin in, the
compression housing.
1. INSTALLATION OF CLUTCH HUB
(1) Connect the magnetic clutch to the battery.
(2) The clutch hub will be attracted to and fit closely to the
rotor.(3) Use
‘a shim(s) to adjust so that the -amountof
movement of the clutch hub is as described below.
Standard value:
0.35-0.65 mm (.014-.026 in.)
NOTERemove clearance adjusting shims to decrease clutch
clearance. Add shims selected from the following table
to increase clutch celarance.
Clearance Adjustment Shims
Part No.Thickness
I949013-74801 0.1 mm (.004 in.)1
I949013-76801 0.2 mm LOO8 in.)1949013-75100.5 mm
LO20 in.)I
3 , z,0’i,,,

24-46HEATERS AND AIR CONDITIONING - c donenser and Condenser Fan Motor
20A0407-INSPECTION
ntarTual Check the condenser fin for crushing or other damage.,
l Check the condenser’s high-pressure hose and pipe in-
stallation parts for damage or deformation.
l Check the condenser fan shroud for damage.
CONDENSER FAN MOTOR CHECK
(1) Disconnect the connection of the connector for the
condenser fan motor.
(2) Check to be sure that the condenser fan motor operates
when battery voltage is applied to terminal
@I and terminal
@ is grounded.
RESISTOR CHECK(1) Disconnect the connection of the connector for the
resistor, and then measure the resistance between termi-
nals.(2) The condition can be considered satisfactory if the mea-
sured resistance is within the range noted below.
Standard value:
0.26-0.32 52SERVICE POINTS OF
INSTALLATtONN24lVAE8. CONNECTION OF LIQUID PIPE/7. DISCHARGE PIPE
Refer to
P.24-23.