AC system FORD MUSTANG 2003 Workshop Manual

GENERAL PROCEDURES
Vacuum Hose Repair —
Mini-Tube
1. Measure the length of the damaged area of the mini-tube vacuum hose.
2. Cut a piece of standard 1/8 inch inner diameter vacuum hose approximately 25 mm (1 inch longer than the damaged area of the mini- tube vacuum hose).
3. Cut off the mini-tube vacuum hose on each side of the damaged area.
4. WARNING: Read the warning information on the product label to prevent possible
personal injury.
Dip the mini- tube hose ends in commercially available paint thinner containing methyl ethyl
ketone (MEK). This solvent will seal the mini- tube in the vacuum hose.
5. Insert the ends of the mini- tube vacuum hose approximately 9 mm (3/8 inch) into the ends of
the standard 1/8 inch repair vacuum hose section.
6. Shake the repair joint after assembly to make sure the solvent is dispersed and the vacuum line is not plugged.
7. Test the system for a vacuum leak in the repair area. zUse the Vacuum Tester or equivalent.
SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Special Tool(s)
Vacuum Pump Kit
416-
D002 (D95L-7559- A) or
equivalent Klj . 1 ba
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DESCRIPTION AND OPERATION
Air Distribution
NOTE:
The air distribution system of this vehicle cannot be equipped with a cabin air filter.
There are two sources of air available to the air distribution system:
zoutside air
z recirculated air
Recirculated air is only used during MAX A/C.
Air distribution within the vehicle is determined by the function selector switch position. Airflow control
doors are used to direct airflow within the air plenum chamber. Vacuum control motors (18A318) are
used to position these airflow control doors. Refer to Section 412 - 00 for a description and operation of
each of the system functions.
The air distribution system is designed to provide airflow from the defrost nozzle when no vacuum is
applied to any of the vacuum control motors. This is done to prevent a situation where defrost cannot
be obtained due to a system vacuum leak.
Air enters the passenger compartment from the:
zinstrument panel A/C register (19893).
z heater outlet floor duct (18C433).
z windshield defroster hose nozzle (18490).
z side window demisters.
Passenger compartment air is exhausted from the vehicle through open windows or body air vents.
Instrument Panel Registers
There are A/C registers on the left and right sides of the instrument panel and in the center instrument
panel finish panel.
The LH and RH A/C registers are only serviceable as assemblies.
The center A/C registers are not serviceable as assemblies. The registers are installed with the
instrument panel center finish panel assembly. Component Locations SECTION 412-
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SPECIFICATIONS
SECTION 412-
02: Heating and Ventilation 2003 Mustang Workshop Manual General Specifications
Item Specification
Lubricant
MERPOL® ESE-
M99B144-
B PAG Refrigerant Compressor Oil (R-134a Systems) F7AZ-19589-
DA (Motorcraft
YN- 12-C) WSH-
M1C231- B
Torque Specifications Description Nm lb-
in Interior evaporator core housing bracket nut and bolts 8 71 Klj . 1 ba
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DESCRIPTION AND OPERATION
Heating and Defrosting
The heating and defrosting system has the following features:
zControls the temperature and, during A/C operation, reduces the relative humidity of the air
inside the vehicle.
z Delivers heated or cooled air to maintain the vehicle interior temperature and comfort level.
z Controls the A/C blower motor speed.
z Cooling or heating can be adjusted to maintain the desired temperature.
z System uses a reheat method to provide conditioned air to the passenger compartment.
z The blower motor (19805) draws outside air through the air inlet duct from just below the
windshield during all system operations except for MAX A/C cooling (when recirculated air is
used).
z All airflow from the blower motor passes through the A/C evaporator core (19860).
z The temperature is then regulated by reheating a portion of the air and blending it with the
remaining cool air to the desired temperature.
z The temperature blending is varied by the air temperature control door, which regulates the
amount of air that flows through and around the heater core (18476), where it is then mixed and
distributed.
Heater Core
The heater core (18476) consists of fins and tubes arranged to extract heat from the engine coolant
and transfer it to air passing through the heater core. Blower Motor SECTION 412-
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The A/C blower motor (19805 ) pulls air from the air inlet and forces it into the plenum assembly where
it is mixed and distributed.
Heater Hoses
NOTE:
The heater water hoses connect to the heater core using quick disconnect couplers. The
couplers are an integral part of the hose assemblies and cannot be separately serviced.
The heater water hoses (18472) provide a flexible connection between the engine and cooling system
allowing hot water to travel from the engine to the heater core. Klj . 2 ba
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REMOVAL AND INSTALLATION
Evaporator Core Housing
Removal
NOTE:
The evaporator core is not separately serviceable, it is serviced only with the evaporator core
housing assembly.
1. Disconnect the battery ground cable.
2. Recover the refrigerant. For additional information, refer to Section 412 - 00 .
3. Drain the cooling system. For additional information, refer to Section 303 - 03A or
Section 303 -
03B .
4. Remove the instrument panel. For additional information, refer to Section 501 - 12 .
5. Disconnect the heater hose couplings from the heater core. For additional information, refer to Section 412 - 00 .
6. Disconnect the vacuum connector. SECTION 412-
02: Heating and Ventilation 2003 Mustang Workshop Manual Material
Item Specification
PAG Compressor Oil (R-134a
Systems)
F7AZ- 19589- DA (Motorcraft
YN- 12-C) WSH-
M1C231-
B MERPOL®
NA ESE-
M99B144-
B Klj . 1 ba
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SPECIFICATIONS
SECTION 412-
03: Air Conditioning 2003 Mustang Workshop Manual General Specifications
Item Specification
Lubricant
PAG Refrigerant Compressor Oil (R-134a Systems) F7AZ-19589-
DA (MC YN-12-
C) WSH-
M1C231-
B
Torque Specifications Description Nm lb-
ft lb-
in A/C compressor mounting bolts 25 18 —
A/C manifold retaining bolt 20 15 —
3.8L engine A/C compressor mounting bracket bolts 47 35 —
3.8L engine A/C compressor mounting bracket nut 25 18 —
A/C compressor clutch retaining bolt 13 10 —
Suction accumulator/drier clamp screw 8 — 71
Coolant bottle bolts 10 — 89
Peanut fittings 8 — 71
Radiator bracket bolts 9 — 81
Condenser core bracket bolts 5 — 44
A/C muffler bracket nut 25 18 — Klj . 1 ba
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DESCRIPTION AND OPERATION
Air Conditioning
The A/C refrigerant system is a clutch cycling orifice tube type. The system components are:
zA/C compressor (19703)
z A/C clutch (2884)
z A/C condenser core (19712)
z A/C evaporator core (19860)
z suction accumulator (19C836)
z connecting refrigerant lines
The refrigeration system operation is controlled by the:
zA/C evaporator core orifice (19D990).
z A/C cycling switch (19E561).
z A/C compressor pressure relief valve (19D644).
z Refrigerant containment switch (3.8L) (19D594).
z Dual- function pressure switch (4.6L) (19D594).
The refrigerant system incorporates an A/C compressor controlled by an A/C cycling switch.
The A/C cycling switch senses A/C evaporator core pressure to control A/C compressor operation.
An A/C compressor pressure relief valve is installed in the A/C manifold and tube (19D734) to protect
the refrigerant system against excessively high refrigerant pressures.
An evaporator core orifice is installed in the A/C evaporator core inlet tube to meter the liquid
refrigerant into the A/C evaporator core.
A refrigerant containment switch is installed on 3.8L vehicles to cut- off A/C compressor operation in
the event of abnormally high refrigerant system pressure.
A dual- function pressure switch is used on 4.6L vehicles for cooling fan control, and to cut- off A/C
compressor operation in the event of abnormally high refrigerant system pressure. Refrigeration System Components SECTION 412-
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An A/C compressor pressure relief valve is incorporated into the compressor A/C manifold and tube to:
zrelieve unusually high refrigerant system discharge pressure buildups. For specifications
regarding operating pressure(s), refer to Section 412 - 00 .
z prevent damage to the A/C compressor and other system components.
z avoid total refrigerant loss by closing after the excessive pressure has been relieved.
A/C Condenser Core
The A/C condenser core has the following characteristics:
zIt is an aluminum fin and tube design heat exchanger located in front of the vehicle radiator
(8005).
z It cools compressed refrigerant gas by allowing air to pass over fins and tubes to extract heat
and by condensing gas to liquid refrigerant as it is cooled.
Refrigerant Lines
The condenser to evaporator tube (19835) contains the high pressure liquid refrigerant upstream of the
evaporator core orifice.
The A/C manifold and tube (19D734) is attached to the A/C compressor, is sealed with O- ring seals,
and has the following features:
zThe upstream side contains low pressure refrigerant gas.
z The downstream side contains high pressure refrigerant gas and a fitting used to mount a
serviceable high pressure A/C charge port valve.
z The downstream side also contains a fitting used to mount the refrigerant containment switch
(3.8L) or dual- function pressure switch (4.6L). A long- travel Schrader-type valve stem core is
installed in the fitting so that the switch can be removed without discharging the A/C system. Klj . 4 ba
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A/C Evaporator Core
NOTE:
The evaporator core is not separately serviceable, it is serviced only with the evaporator core
housing assembly.
NOTE: Installation of a new suction accumulator is not required when repairing the air conditioning
system except when there is physical evidence of contamination from a failed A/C compressor or
damage to the suction accumulator.
The A/C evaporator core is the plate/fin type with a unique refrigerant flow path.
zA mixture of refrigerant and oil enters the bottom of the A/C evaporator core through the A/C
evaporator core inlet tube and moves out of the A/C evaporator core through the A/C
evaporator core outlet tube.
z This flow pattern accelerates the flow of refrigerant and oil through the A/C evaporator core.
Evaporator Core Orifice
NOTE: The evaporator core orifice is an integral part of the condenser to evaporator line and should
be installed as an assembly with the line.
NOTE: A new evaporator core orifice should be installed whenever a new A/C compressor is installed.
The evaporator core orifice has the following characteristics:
zIt is located in the A/C condenser to evaporator line.
z It has filter screens located on the inlet and outlet ends of the tube body.
z The inlet filter screen acts as a strainer for the liquid refrigerant flowing through the evaporator
core orifice.
z O-ring seals on the evaporator core orifice prevent the high- pressure liquid refrigerant from
bypassing the evaporator core orifice. Klj . 5 ba
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