1991 MITSUBISHI ECLIPSE Service Manual

24-l
HEATERS ANDAIR CONDITIONING
CONTENTSN24M--AIR CONDITIONER SWITCH
..........................30BLOWER ASSEMBLY
.....................................33
COMPRESSOR.................................................37CONDENSER AND CONDENSER FAN
MOTOR............................................................45ENGINE COOLANT TEMPERATURE
-‘-.,SWITCH............................................................51
EVAPORATOR.................................................
34
HEATERCONTROLASSEMBLY....................
26HEATER UNIT
.................................................31
REFRIGERANTLINE........................................47
RESISTOR........................................................29SAFETY PRECAUTIONS
.................................10SERVICE ADJUSTMENT PROCEDURES..
.....11Compressor Drive
Belt Adjustment
.............
23
CompressorNoise........................................24
Handling
TubingandFittings.......................22Idle-up
OperationCheck..............................25Manifold
GaugeSetInstallation..................11Performance Test
.........................................16Power Relay Check
......................................24Refrigerant Leak Repair Procedure
.............17
TestingSystemforLeaks...........................15Test Procedures
...........................................11
SPECIFICATIONS.............................................2
General Specifications..................................2
Lubricants......................................................3Sealant and Adhesives
.................................3Service Specifications
...................................2
TorqueSpecifications...................................2
TROUBLESHOOTING. . . ..a................................3
VENTILATORS(AIR INLET AND AIR OUTLET)
..,....s............. 50
VENTILATORS(INSTRUMENT PANEL)
..,...................*...........49

24-2HEATERS AND AIR CONDITIONING - Specifications
SPECIFICATIONS
GENERAL SPECIFICATIONSN24cA- -
ItemsSpecifications
Heater unit
TypeThree-way-flow full-air-mix system
Heater control switchDial type
Compressor
Model
lOPARefrigerant unit lubricantcc
(cu.in.1DENS0 OIL 6 or SUNISO 5GS80f20 (4.9&l .2)
V belt sizemm (in.)<1.8L Engine> 920 (36.2)<2.0L DOHC Engine> 940 (37.0)Dual pressure switch
High pressure switch
kPa (psi)OFF: 2,700 (384)ON: 2,100 (299)
Low pressure switch
kPa (psi)OFF: 210 (30)ON: 235 (33)
Freezer prevention“C (“F)Air temperature thermostat
OFF: 3 (37.4)ON: 4 (39.2)
Refrigerant and quantity
g bdR-12MAX 935 (33)
SERVICE SPECIFICATIONSN24CB.-
ItemsSpecifications
Standard valueAir
therm0 sensor and air inlet sensor standard
resistance value
n0°C (32°F)4,852f24315°C (59°F)2,341 f23425°C 177°F)1,500f 150Engine coolant temperature switch
Switch-OFF temperature
“C (“F) 112-118 (233-244)
Amount of
V belt deflection
mm (in.)
When new belt installed4-5
(.16-.2)When used belt installed5.5-6
(.22-.24)Amount of V-ribbed belt deflection
mm (in.)
When new belt installed4.5-5
(.18-.2)When used belt installed5.5-6
(.22-.24)
Clutch clearancemm (in.) 0.35-0.65 (.014-,026)
Condenser fan motor resistor resistance value
52 0.26-0.32
TORQUE SPECIFICATIONSN24CC-
ItemsNmft.lbs.Front housing installation bolt
24-2818-21
Compressor bracket tightening bolt
45-5533-39
Compressor tightening bolt
23-2717-19
Tension pulley center nut (bolt)
32-4824-36
Dual pressure switch
9-117-8
Engine coolant temperature switch
30-4022-28
k
- /.

HEATERS AND AIR CONDITIONING - Specifications/Troubleshooting24-3LUBRICANTS
u24as-
;xiItemsSpecified lubricantsQuantity
Each connection of refrigerant lineDENS0 OIL 6 or
SUNISO 5GSAs required
Shaft seal of the compressor
SEALANT AND ADHESIVES, Items
Engine coolant temperature switch threaded partSpecified sealant and adhesive
MOPAR Part No.4318034 or equivalentN24CE-
TROUBLESHOOTINGN24EBAQ
SymptomHeater insufficient heat
No ventilation even when
mode selection knob is
operatedBlower motor inoperative
Probable causeObstructed heater outlets
Blend air dampers improperly adjusted or bindingThermostat malfunction
Obstructed heater hoses
Improperly adjusted control cables
Plugged or partially plugged heater core
Incorrect adjustment of mode selection dampersIncorrect installation of mode selection control wire
Ducts are incorrectly/incompletely connected, crushed,
bent or clogged.
Poor grounding
Burnt-out fuseMalfunction blower switch
Malfunction resister
Malfunction blower motor
Malfunction heater relay
Remedy
Correct
ReplaceAdjust
Clean or replaceAdjust
Repair or replace
Correct
Replace

24-4HEATERS AND AIR CONDITIONING - Troubleshooting
TROUBLESHOOTING QUICK-REFERENCE TABLE
Compressor doesn’t operate.Air conditioner switch: ON
1
Can the activation sound of theYesThe compressor magnetic clutch
magnet clutch be heard when
- is normal. The compressor body is
battery voltage is applied to the airabnormal.
conditioner compressor magnet
clutch?
Is the voltage Bv between ground
and terminal
(4) of the airconditioner switch equivalent to
battery voltage when’the air
conditioner switch is pressed in
one step?
Is the voltage Bv between ground
and terminal
(2) of the airconditioner switch equivalent to
batten/ voltage when the air
conditioner switch is pressed in
two steps?
YesIs there continuity between
terminals (2) and (4) of the
magnetic clutch relay?
Is there continuity between
terminals (1) and (3) when Bv is
applied between terminals
(2) and
(4)?
L
i
I
Yes
Is the high-pressure siderefrigerant pressure within the
range of 21 O-2,700 kPa (29.9-
384 psi) when a gauge manifold
is connected to the service valve
and the high-pressure side
refrigerant pressure is measured?
/YesMalfunction of the air conditioner
switch.
Refer to P.24-6.
r
1!
\loMalfunction of the magnetic
clutch relay.
Gas leakage or excess refrigerant.Is there continuity between the
dual-pressure switch terminals?
No_ Malfunction of the dual-pressure
switch.
Yes
Continue to next page.

HEATERS AND AIR CONDITIONING - Troubleshooting24-5
From previoys page.
When the resistance of the air-
therm0 sensor is measured[with the air conditioner switch
OFF and when the ambient
temperature of the
air-therm0sensor is
25°C (77“F)], is the
measured resistance approx.
1.5f0.15 kP?
INoMalfunction of tha air-therm0Refer to P.24-6.-sensor.
Refer to P.24-6.
1Yes
When the resistance of the air-
inlet sensor is measured [with the
air conditioner switch OFF andwhen the ambient temperature of
the air-inlet sensor is 25°C (77”F)l
is the measured resistanceapprox.
1.5f0.15 k&2?I
1 Yes
Does idle-up occur immediatelyNo Malfunction of the DC motor
after the air conditioner switch is
cl800 Engine>
switched ON?Malfunction of the stepper motor
Yes~2000 DOHC Engine>
Malfunction of the MPI control unit
* Malfunction of the air conditioner
control unit.Refer to P.24-6.

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.

HEATERS AND AIR CONDITIONING - Troubleshootinq
-.
’ Wire harness sideTROUBLESHOOTING HINTS
Inspection of Air Conditioner Control Unit
Disconnect the amplifier and inspect the connector on the wireharness side as shown in the chart below.
Test Conditions:
(1) Ignition switch: ON
(2) Air conditioner switch: ON
(3) Temoerature control lever: MAX COOL2OAO405
(4j Bloier switch: HI
TerminalMeasurement item
Tester connectionConditions
Specified value
1Resistancel-6-1,500f150 sz ’at 25°C (77°F)
2
10
Voltage2-3
2-8Airtcchonditioner
ContinuityContinuity3-Ground
4-Ground
Resistance5-7
-ContinuityII
8-Ground-
Voltage9-3
9-8Therm0 sensor OFF78°C (172°F)
:5k (185°F)
Voltage10-3ECONO switch
10-8
System voltageov
Continuity
Continuity1,500+
150 s-2at 25°C (77’F)
Continuity
System voltageov
System? voltageov
If the connector on the wire harness side is correct, replace the air conditioner control unit.

24-8HEATERS AND AIR CONDITIONING - Troubleshooting
IARNESSES AND COMPONENTS LAYOUT DIAGRAM
1. Air conditioner switch
2. Air conditioner control unit
3. Air-inlet sensor
4.
Air-therm0 sensor
36AOO51
NameSymbolAir conditioner control unit
DAir conditioner switch
GAir inlet sensor
FAir
therm0 sensorFBlower motor High relay
E
IrrIor:enser fan motor High-Low selecting
C
NameCondenser fan motor relay
Dual pressure switch
Engine coolant temperature switch
<2.0L DOHC Engine>
Heater relay
Magnetic clutch relay
Symbol
C
BA
H
C
NOTEThe “Name” column is arranged in alphabetical order.
q \
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