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General
The purpose of the air conditioning unit is to produce a decrease of the tempera ture in t he
passengers compartment a nd to obt ain a l ower value tempera ture c ompare d to the e xterna l
environment one, reducing in the same time the air moisture.
MAINTENANCE
For a vehicle equipped with air conditioning, during the year it is recommended:-the checking of the refrigerant fluid filling;
- the cleaning and the air-blowing of the condenser and the cooling radiator fins;
- the checking of the condensation removal pipe on order not to be clogged.
For important leakage repair, for any components replacement (compressor, condenser, etc)
and if moisture was noticed in the air conditioning circuit, replace the dryer filter tank and drain
the unit; the same is valid also in case the conditioning circuit remains open without protection
covers more than 10 minutes.
IMPORTANT !
During winter, it is recommended the frequent start of the system, in order to prolong
the lifetime of t he compressor and of the whole system.
T he vehicle equipped with an air c onditioning system shall be not exposed for more
than 20 minutes i n painting c abin where there are temperatures higher than 80 °C.
It is obligatory the use of t he refrigerating agent and compressor oil type prescribed
by the manufacturer.
It is absolutely forbidden to perform welding works on the elements of the ai r condition
circ uits.
The fi lling of the air c onditioning system c an be pe rformed only by means of c harging
units and observing the instructions of the manufacturer. For mechanical or body
operations it is recommended piping protection in order to avoid t heir disconnection
by accident.
Avoid the drip of the oil compressor on the painted vehicle carriage body.
For component replacement implying t he circuit draining, it is absolutely necessary
the use of new parts and of a special oil for compressor.
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Condenser
SPECIAL TOOLS
MOT 453Hoses clamp
MOT 1202-01 Elastic clips pliers
The condenser is placed on the c ooling
radiator, ensuring the exhaust of the refrigerant
heat accumulated at compression.
DISMOUNTING
Disconnect the battery.
Drain the AC unit and recover t he oil and
the refrigerant fluid at the charging station.
Dismount the front grill.
Dismount the air filter inlet pipe.
Dismount the engine fan off the radiator.
Disconn ect the pipes from the condenser and
immediately close the disconnected pipes ends
and the condenser connections with protection
caps in order to avoid humidity and impurities
penetration in circuit.
Clamp the hoses from the radiator by means
of the MOT 453 device.
Di smount the hoses from the radiator by
means of the elastic clips pliers MOT 1202-01 ,
recovering the cooling fluid.
Dismount the radiator side attachment
supports on the radiator upper cross beam and
release the radiator together with the condenser.
Re l e a se t he condense r f rom t he four
attachment screws on the radiator.
REMOU NT I NG
Perform the dismounting operations in the
reverse order.
Tighten to t he required m oment the pipes
nut s .
- thread 3/4 “ 1,8 – 2,2 daNm
- thread 5/8 “ 1,0 – 1,4 daNm
Fill the AC unit with refrigerant fluid HFC
134a (0,600 Kg) by means of the charging unit.
Check for refrigerant fluid leaks.
Fill and purge the cooling circuit.
Check the good operation of the AC unit.
REMARK :
When mounting, line up the marks of
the hoses and mating parts .
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Pressure controller
LOCATION
Pressure controller (1) is located on the high-
pressure pipe, near the dryer reservoir.
FUNCTION
The pre ssure control ler is perm anently
informing UCE (electronic control unit) about
the circuit pressure. Subject to pressure value in the high-
pressure circuit, UCE is commanding:
- circuit break ( by uncoupling the compressor
clutch) when the pre ssure in the c ircuit is
decreasing under 1,96 + /-0,2 bar a nd clutch
coupling when the pressure is over 2,16 +/-
0,2 bar;
- circuit break when the pressure in the circuit
is over 31,4 +/- 2 bar and compressor clutch
coupling when the pressure is decreasing under
25,5 +/- 2 bar;
- engine fan starting on second speed, when
the pressure is over 17,7 +/- 1 bar and engine
fan stopping when the pressure is decreasing
under 13.7 +/- 1 bar.
REPLAC EMEN T
The pressure controller replacement does
not imply the draining of the refrigerant circuit. Disc
onnect the pressure controller
connector.
Replace the pressure controller.
When m ounting, lubricate the pressure
controller sealing gasket with oil PAG SP 10.
T ighten the pressure controller to the required
moment of 0,9 +/- 0,1 daNm.
Check for refrigerant fluid leaks.
1
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Filter reservoir
Filter reservoir (1) is attached by means of a
support collar on the right longitudinal girder.
Its function in the AC unit operation is : -filtering the refrigeran t fluid;
-r etaining the humidity from the unit;
-f orming of a buffer stock of refrigerant
fluid.
The particles interception is necessary because
it might block the thermostatic expansion vale
operation or produce compressor mobile parts
wear or gripping. The filter reservoir is not to be repaired.
DISMOUNTIN G
Disconnect the battery.
Drain the AC unit.
Dism ount t he pi pi ng a nd pro t e c t wi t h
protection caps in order to avoid humidity
penetration. Dismount the filter reservoir off the support
collar and release it.
REMOU NT I NG
Perform the dismounting operations in the
reverse order. Fill the AC unit with refrigerant fluid HFC
134a (0,600 Kg) by means of the c harging
station.
Check for refrigerant fluid leaks.
When replacing the filter reservoir, fill in
the circuit with 15 ml of oil PA G S P 10 .
REMARK
The tightening required moment of
the pipes nuts at the filter reservoir is of
1,4 –2 daNm.
The required tightening moment of
the attachmen t screw of the filter
re servoir support is of 0,7 daNm.
1
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Unit piping
TIGHTENING MOMENTS(daNm)
Pipe attachment nut 3/4’’on condenser 1,8-2
Pipe attachment nut 5/8’’on condenser 1-1,4
P ipes attachment screw on compressor 1,2
Pipes attachment nut on evaporator 0,57
The AC unit piping is ensuring the refrigeran t
fluid circulation between the unit components.
When piping is replaced, check the existence
of the protective caps, the l ubrication of the
connections and gaskets with compressor oil.
The unit fillin g and draining valves are placed
on the c ompressor piping a nd they different
diameters, so that they can not be reversed.
COMPRESSOR – EVAPORATOR
LO W PRESSURE PIPE
DISMOUNTIN G
Disconnect the battery.
Drain the AC circ uit by means of the
charging unit.
Dismo unt :
-atta chme nt nu t ( 9) of t he pi pe s
tightening clamp on evaporator ( 8) (located in
DSAF); -attachment screw ( 6) of the pipes
tightening clamp on compressor ( 5);
- attachment screw (7) of pipes clamp.
Release the pipe ( 10) and mount protection
caps at its extremities, at evaporator and
compressor.
R EMOU NT I NG
Perform the dismounting operations in the
reverse order.
Replace the gaskets from pipe’s extremities.
Before m ounting, t he ga skets are to be
lubricated with oil PAG SP 10.
In case pipe ( 10) is replaced, add 10 ml of
oil PA G S P 10, and in case of its breaking,
100 ml.
COMPRESSOR – CONDENSER
HIGH PRESSURE PIPE
DISMOUNTIN G
Disconnect the battery.
Drain th e AC circu it by means of the
charging unit. Dismo unt :
- front grill;
-atta chme nt sc rew (6) of t he hi gh
pressure pipe (4) on compressor (5);
-pipe attachment nut on condenser ( 12);
-pipe att achment clamp ( 11) on
condenser.
7
1
10
9
13
3 4
12 6
5
11 8
2
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Unit piping
Release the pipe and mount protection caps
at its extremities, at compressor and condenser.
REMOU NT I NG
Perform the dismounting operations in the
reverse order. Replace the gaskets and lubricate them with
oil PA G S P 10.
When a pipe is replaced, add 10 ml of oil
P AG SP 10 and in case of its breaking, 100 ml.
AT T E N T I O N !
Aft e r m ount ing t he AC uni t pi pi ng,
check for refrigerant fluid leaks.
FILTER RESERVOIR –
EVAPORATOR HIGH PRESSURE
PIPE (DSAF)
DISMOUNTIN G
Disconnect the battery.
Drain the AC circuit.
Disconnect the pressure controller connector
(2). Dismou nt :
-attac hm e n t n u t ( 9) of th e p i pe s
tightening clamp on evaporator ( 8);
- attachment nut of the high pressure pipe
(1 ) on filter reservoir;
- attachment screw (7) of pipes clamp.
Release the pipe ( 1) and mount protection
caps at its extremities, at evaporator and
reservoir filter ( 13).
REMOU NT I NG
Perform the dismounting operations in the
reverse order.
Check the condition of the gasket and
lubricate them with oil PAG SP 10.
When re placing a pipe, add 10 ml of oil
P AG SP 10 and in case of its breaking, 100 ml.
The “ 0” rings from the pipe extremities are to
be replaced with new ones.
FILTER RESERVOIR – CONDENSER HIGH PRESSURE PIPE
DISMOUNTIN G
Disconnect the battery.
Drain the AC circuit.
Dismount the attachment nuts of the high-
pressure pipe ( 3) on filter re servoir and con-
denser. Release the pipe and mount protection caps
at pi pe’s e xtremities ( 3), at condenser a nd at
filter reservoir.
7
1
9
13
34 126
5
11 8
2
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REMOU NT I NG
Perform the dismounting operations in the reverse order.
The “ 0” rings from the pipe’s extremities are to be replaced with new ones. Before mounting,
these are to be lubricated with oil PA G S P 10.
When replacing a pi pe, add 10 ml of oil PA G S P 10 and in case of its breaking – 100 ml.
AT T E N T I ON !
After m ounting the AC unit piping, check for refrigerant fl uid leaks.
Unit piping
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INSTRUMENT PANEL
83
83 - 8
Diagnostic – damages interpretation
Check the oil pressure.
Pr essure is correct?
Replace the oil pressure transmitter. There is a failure in the oil circuit.
Fix it.
OIL P RESSURE INDICATOR IS NOT ON WHEN CONTACT SET ON
Place the wire from the oil pressure
transmitter to the mass Is the indicator on ?
Replace the oil
pressure transmitter Replace the bulb.
Wa r
ning indicator bulb is
worn?
Check the bulb supply wiring and fix it.
FUEL LEVEL INDICATOR SHOWING ALWAYS FULL
Replace the fuel level transmitter.
Replace the instrument panel. Disconnect the connection wire t o the probe.
Is the fuel level indicator showing zero ?
Resistance against the vehicle mass of the B1 pin
of the fuel level transmitter connector is zero?
Defective wiring. Fix it.Ye s
No
Ye s N o Ye sNo
Ye s No No
Ye s
OIL PRESSURE INDICATOR STILL ON
AFTER ENGINE STARTING
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