2000 MITSUBISHI MONTERO compressor

HEATER, AIR CONDITIONER AND VENTILATION - Service Specifications/Lubricants55A-3
SERVICE SPECIFICATIONS
ItemStandard value
Idle speed r/minDiesel4D56750±100
(N or P range)4M41750±50
Idle-up speed r/min4D56925±25
(N or P range)4M41A/CWhen the
A/C is under
low or me-
dium load800±50
When the1,000±50
A/C is under
high load
Water temperature switch_CA/C cut-offON108
OFF11 5
Condenser fanOFF97
ON102
Resistor resistance (Front A/C)WBetween terminals 2 and 40.39±7%
Between terminals 1 and 21.49±7%
Between terminals 2 and 32.79±7%
Resistance of the rear air conditioner switch (temperature control switch) kW
0-3
Potentiometer for air mix damper kW1.2 - 4.8
Resistor resistance [Rear heater (frontBetween terminals 1 and 64.9±7%
console)]WBetween terminals 1 and 31.25±7%
Resistor resistance [Rear heater (quarterBetween terminals 1 and 64.9±7%
trim), rear heater]WBetween terminals 1 and 31.25±7%
Idle-up solenoid valve resistanceW40
Air compressor air gap mm0.35 - 0.65
LUBRICANTS
ItemSpecified lubricantsQuantity
Compressor oil mLExcept for vehicles with rear coolerDENSO OIL 8120±20
Vehicles with rear coolerDENSO OIL 8140±20
Pipe connectionsDENSO OIL 8As required
Refrigerant gExcept for vehicles with rear coolerR134a (HFC-134a)500±20
Vehicles with rear coolerR134a (HFC-134a)780±20


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HEATER, AIR CONDITIONER AND VENTILATION - Troubleshooting55A-4
TROUBLESHOOTING
Trouble symp-
tomProbable causeRemedyRefer-
ence
page
The air condi-Malfunction of fuseReplace the fuse.–
tioner does notMalfunction of harness or connectorRepair the harness or connector.–work.
Refrigerant leak or overfilling of refrigerantReplenish the refrigerant, repair the leak
or take out some of the refrigerant.–
A/C compressor relay is defective.Replace the A/C compressor relay.55A-18
The A/C compressor magnetic clutch is
defective.Replace the A/C compressor.55A-10
The dual pressure switch is defective.Replace the dual-pressure switch.55A-10
The A/C switch is defective.Replace the heater control assembly.55A-24
The blower switch is defective.Replace the heater control assembly.55A-24
The air thermo sensor is defective.Replace the automatic compressor-ECU
and the air thermo sensor assembly.55A-31
The automatic compressor-ECU is defec-
tive.Replace the automatic compressor-ECU
and the air thermo sensor assembly.55A-6
The engine-ECU is defective.Replace the engine-ECU.–
When the A/C
is operating,Refrigerant leakReplenish the refrigerant and repair the
leak.–
temperature
inside the pas-The dual pressure switch is defective.Replace the dual-pressure switch.55A-10inside the pas-
senger
The condenser fan relay is defective.Replace the condenser fan relay.55A-18compartment
doesn’t de-
A/C compressor relay is defective.Replace the A/C compressor relay.55A-18
crease (cool
air is not
emitted).The A/C compressor magnetic clutch is
defective.Replace the A/C compressor.55A-10
When the A/C
is operating,
temperature
inside the pas-
senger
compartment
doesn’t in-
crease (warm
air is not
emitted).Malfunction of the air thermo sensorReplace the automatic compressor-ECU
and the air thermo sensor assembly.55A-31
The blowerMalfunction of fuseReplace the fuse.–
motor does notMalfunction of harness or connectorRepair the harness or connector.–run.
The blower relay is defective.Replace the blower relay.55A-18
The blower motor is defective.Replace the blower motor.55A-29
The blower switch is defective.Replace the heater control assembly.55A-24
Malfunction of the resistorReplace the resistor.55A-29
The automatic compressor-ECU is defec-
tive.Replace the automatic compressor-ECU
and the air thermo sensor assembly.55A-6


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HEATER, AIR CONDITIONER AND VENTILATION - On-vehicle Service55A-17
REFRIGERANT LEAK REPAIR
LOST CHARGE
If 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 in storage. 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 for quick reassembly to avoid keeping
the system open any longer than necessary.
7. Evacuate and charge system.
LOW CHARGE
If the system has not lost all of its refrigerant charge;
locate and repair all leaks. If it is necessary to
increase the system pressure to find the leak
(because of an especially low charge) add
refrigerant. If it is possible to repair the leak without
discharging the refrigerant system, use the
procedure for correcting low refrigerant level.HANDLING TUBING AND FITTINGS
Kinks in the refrigerant tubing or sharp bends in
the refrigerant hose lines will greatly reduce the
capacity of the entire system. High pressures are
produced in the system when it is operating.
Extreme care must be exercised to make sure that
all connections are pressure tight. Dirt and moisture
can enter the system when it is opened for repair
or replacement of lines or components. The
following precautions must be observed. The
system must be completely discharged before
opening any fitting of connection in the refrigeration
system. Open fittings with caution even after the
system has been discharged. If any pressure is
noticed as a fitting is loosened, allow trapped
pressure to bleed off very slowly.
Never attempt to rebend formed lines to fit. Use
the correct line for the installation you are servicing.
A good rule for the flexible hose lines is keep the
radius of all bends at least 10 times the diameter
of the hose.
Sharper bends will reduce the flow of refrigerant.
The flexible hose lines should be routed so that
they are at least 80 mm from the exhaust manifold.
It is good practice to inspect all flexible hose lines
at least once a year to make sure they are in good
condition and properly routed.
Unified plumbing connections with O-rings, these
O-rings are not reusable.
COMPRESSOR 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 A/C operation can often
be 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 accessory 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 problems within the
compressor.ADJUSTMENT
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.
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.


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55B-1
HEATER, AIR
CONDITIONER AND
VENTILATION

CONTENTS
SERVICE SPECIFICATIONS 2.................
LUBRICANTS 2..............................
SPECIAL TOOLS 3...........................
TROUBLESHOOTING 3........
TROUBLESHOOTING 3.........
ON-VEHICLE SERVICE 24...................
Magnetic Clutch Test 24.........................
Idle Up Operation Check 25.............
FRONT A/C 25..............................
Automatic A/C Control Panel Assembly
(A/C-ECU) 25..................................Blower Linear Controller 26......................
Air Mix Damper Motor and
Air Outlet Changeover Damper Motor 27..........
Heater Water Temperature Sensor 29.............
PHOTO SENSOR 30........................
OUTSIDE AIR TEMPERATURE SENSOR 30..
REAR A/C 30...............................
Electric Motor for Air Outlet Changeover
Damper 30....................................
REFRIGERANT LINE 31.....................
COMPRESSOR 33...........................


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HEATER, AIR CONDITIONER AND VENTILATION -Service Specifications/Lubricants55B-2
SERVICE SPECIFICATIONS
ItemStandard value
Resistance value of the potentiometer for the air mix damper (front A/C) kWApprox. 0.96 - 5.76
Resistance value of the potentiometer for the air outlet changeover damper (front A/C)
kWApprox. 0.96 - 5.76
Resistance of the rear air conditioner switch (temperature control switch) heater (floor console)> kW0-3
Resistance of the potentiometer for the air mix damper kW1.2 - 4.8
Resistance value of the resistor (rear A/C)Between terminals 1 and 64.9±7%
WBetween terminals 1 and 31.25±7%
Air compressor air gap mm0.35 - 0.65
Idle speed r/min (N or P range)Petrol600±50
Idle-up speed r/min (N or P range)PetrolWhen the A/C is under
low load700±50
When the A/C is under
medium load800±50
When the A/C is under
high load1,000±50
LUBRICANTS
ItemBrandQuantity
Compressor oil mlSingle A/C cooler>DENSO OIL 8120±20
Single air conditioner rear cooler>, dual air conditionerDENSO OIL 8140±20
Pipe connectionsDENSO OIL 8As required
Refrigerant gSingle A/C cooler>R134a (HFC-134a)500±20
Single air conditioner rear cooler>, dual air conditionerR134a (HFC-134a)780±20


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HEATER, AIR CONDITIONER AND VENTILATION -Troubleshooting 55B-17
DATA LIST REFERENCE TABLE
Item No.Check itemInspection contents
11Inside air temperature sensorIgnition switch: ONInside air temperature and tempera-
ture displayed on the MUT-IIare
identical.
13Outside air temperature sen-
sorIgnition switch: ONOutside air temperature and tem-
perature displayed on the MUT-II
are identical.
15Heater water temperature
sensorIgnition switch: ONHeater core surface temperature
and temperature displayed on the
MUT-IIare identical.
21Air thermo sensorIgnition switch: ONEvaporator outlet temperature and
temperature displayed on the MUT-
IIare identical.
25Photo sensorIgnition switch: ONAmount of incident light is propor-
tional to voltage displayed on the
MUT-II.
31Potentiometer for the air mix
damperIgnition switch: ON
Damper position: MAX HOTOpening angle: Approximately
100%
Ignition switch: ON
Damper position: MAX COOLOpening angle: Approximately 0%
32Potentiometer for the air
outlet changeover damperIgnition switch: ON
Damper position: FACEOpening angle: Approximately 0%
Ignition switch: ON
Damper position:FOOTOpening angle: Approximately 60%
Ignition switch: ON
Damper position: FOOT/DEFOpening angle: Approximately 80%
Ignition switch: ON
Damper position: DEFOpening angle: Approximately
100%
ACTUATOR TEST TABLE
Item No.Check itemDrive Contents
01Blower motorStopped
02Low speed
03Medium speed
04High speed
05Electric motor for the air mix damperOpening angle: Approximately 0%
06Opening angle: Approximately 50%
07Opening angle: Approximately 100%
08Electric motor for the air outlet changeoverFACE
09damperFOOT
10DEF
11Compressor ON/OFFOFF
12ON
13Inside/outside air changeover damper motorOutside air
14Inside air


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HEATER, AIR CONDITIONER AND VENTILATION -Troubleshooting 55B-19
Termi-
nal No.Normal condition Check conditions Check item
15Rear defoggerRear defogger: OFFSystem voltage
Rear defogger: ON1.5 V or less
16Multi center display unit communication
lineIgnition switch: ONHi: 4 - 5 V
Lo: 0 - 1 V
17Multi center display unit communication
lineIgnition switch: ONHi: 4 - 5 V
Lo: 0 - 1 V
18Multi center display unit communication
line shieldAt all times0V
19Diagnosis outputIgnition switch: ONA voltmeter needle
fluctuates between 0
and 12 V.
20Input from A/C compressor relayWhen the A/C is off.0V
When the A/C is in operation
(When compressor is operating)System voltage
21Power supply to potentiometerAt all times5V
22Input from outside air temperature
sensorSensor temperature: 25
_C (1.7 kW)1.9 V
23Input from heater water temperature
sensorSensor temperature: 25
_C(5kW)2.8 V
24Input from potentiometer for air mix
damperWhen the damper flap is moving to the
MAX HOT position.0.7 - 1.3 V
25Power supply to illuminationLighting switch: ONSystem voltage
26Power supply to ignition switch (IG2)Ignition switch: ONSystem voltage
27Power supply to ignition switch (ACC)Ignition switch: ACCSystem voltage
28Backup power supplyAt all timesSystem voltage
29Earth to sensor and potentiometerAt all times0V
30Input from air thermo sensorSensor temperature: 25
_C (1.5 kW)2.2 V
31Photo sensor (+)During 800 kcal/m2-h1V
32Input from potentiometer for the air
outlet changeover damperWhen the damper flap is moving to the
DEF position.0.7 - 1.3 V
33Diagnosis inputIgnition switch: ON0V
34Compressor lock signal (ignition signal)Engine speed: 3 000 r/min0.3 - 3.0
35Illumination earthAt all timesContinuity
36EarthAt all timesContinuity
CHECK AT ENGINE-A/T-ECU OR ENGINE-ECU TERMINALS
Refer to GROUP 13A – Troubleshooting or GROUP 13B – Troubleshooting .


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