2003 FORD MUSTANG cooling

GENERAL PROCEDURES
Air Conditioning (A/C) System Check —
Retail Procedure
NOTE: This Retail Procedure is not eligible for claiming on Ford paid repairs (warranty and ESP).
NOTE: The engine should be run at idle for 10 minutes with the air conditioning on and set to MAX A/C
before carrying out this retail procedure.
NOTE: Read and follow all of the Warnings, Cautions and Notes at the beginning of this section before
continuing.
1. Visual inspection
Open the hood and visually inspect the heating and air conditioning systems for the following:
zCoolant reservoir for correct coolant level
z Heater hoses for deterioration or loose connections
z Radiator and condenser for debris or damaged fins restricting airflow, loose mounting or
connections
z Accessory drive belt(s) and cooling fan(s) for wear or physical damage
z Refrigerant lines and connections for physical damage or loose connections
z Compressor for physical damage or loose connections
z Suction accumulator/drier for physical damage or loose connections
z Wiring and connectors for excessive wear, loose or damaged connections, or incorrect
routing
2. A/C refrigerant analysis
zCarry out air conditioning refrigerant analysis. For additional information, refer to
Refrigerant Identification Testing in this section.
z If the refrigerant fails the analysis, discontinue diagnosis and make recommendations for
repairs.
z If the refrigerant passes the analysis, carry out the air conditioning system check.
3. Air conditioning system check
zConnect manifold gauge set or charging station with gauges to refrigerant system.
z With the vehicle in park, parking brake set, thermometer installed in center panel vent,
and air conditioning system on and set to MAX A/C, start the engine.
z Record air refrigerant system pressures while running the engine at 1,500 rpm and allow
engine to return to idle.
z Operate the blower motor in all control positions and check for correct blower speed
changes.
z With the blower motor on HI, operate air discharge mode selector in all positions and
check for correct airflow in each position.
z Operate the temperature blend selector in all positions and check for correct change in
discharge temperature. Check the air discharge temperature with the selector in the
coolest position and the air conditioning on and set to MAX A/C to determine if the air
discharge temperature is acceptable for the current ambient air temperature.
z Carry out the EATC self- test (if applicable).
If the refrigerant system pressures were low, carry out the refrigerant system leak test.
SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Klj . 1 ba
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GENERAL PROCEDURES
Heater Hose Coupling
Disconnect
CAUTION: Do not attempt to install a new bushing, spacer or O- rings in the heater hose
coupling; damage to the heater hose coupling can result. If the heater hose coupling is the
cause of a coolant leak, the affected heater hose must be replaced as an assembly.
1. WARNING: The engine must be off, fully cool and the cooling system fully
depressurized before attempting to disconnect any heater water hoses. Failure to comply
with this warning can result in serious injury or burns from hot liquid escaping out of the
engine cooling system.
Depressurize the engine cooling system.
2. Push the heater hose toward the tube to fully expose the locking tabs.
3. NOTE: When compressing the white coupling retainer with the special tool, the special tool
must be perpendicular to and on the highest point of the coupling.
NOTE: If the heater hose coupling is accessible, the retainer tabs can be compressed by hand
to disconnect the heater hose.
Push the special tool over the coupling retainer windows to compress the retainer locking tabs.
SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Special Tool(s)
Remover, Heater Hose Inlet
Tube
412-
042 (T85T-18539- AH) Disconnect Tool, Heater Hose
412-
127
Material Item Specification
MERPOL®
—
ESE-
M99B144- B Klj . 1 ba
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GENERAL PROCEDURES
Refrigerant System Tests
1. Connect the R- 134a Manifold Gauge Set. For additional information, refer to Manifold Gauge Set Connection in this section.
2. Adjust the climate controls for maximum cooling. zStart the engine.
z Select MAX A/C operation.
z Set the blower motor speed to maximum.
3. Stabilize the in- vehicle temperature at 21- 27°C (70-80°F).
4. NOTE: When the ambient temperatures exceed 38°C (100°F), do not run the engine above
normal idle speed.
Maintain the engine speed at 1,500 rpm.
5. Determine the compressor discharge (high) pressure. 1. Record the ambient temperature.
2. Record the discharge (high) pressure.
3.NOTE: In ambient temperatures between 38- 43°C (100-110°F), the system performance
pressures will be the same as those for ambient temperatures shown on the chart in the
32- 38°C (90- 100°F) range.
The system performance is acceptable when the pressure reading falls between the
upper and lower limits shown.
SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Special Tool(s)
R-
134a Manifold Gauge Set
176- R032A or equivalent 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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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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system discharge pressures.
zThe dual- function pressure switch is mounted on a Schrader valve- type fitting on the high
pressure side of the A/C manifold and tube.
z It is not necessary to discharge the refrigerant system to remove the dual- function pressure
switch.
z A valve depressor, located inside the threaded end of the dual- function pressure switch,
presses on the Schrader valve stem.
z This allows the dual- function pressure switch to monitor the compressor discharge pressure.
z When the compressor discharge pressure rises, the switch contacts open, disengaging the A/C
compressor. When the pressure drops, the contacts close to allow operation of the A/C
compressor. For specifications regarding operating pressure(s), refer to Section 412 - 00 .
The dual- function pressure switch has a second set of electrical contacts used for high- speed cooling
fan control.
zWhen the compressor discharge pressure rises, the contacts close and engage the high speed
fan control. When the pressure drops, the contacts open and the high speed fan control is
disengaged.
Refrigerant Containment Switch (3.8L)
The refrigerant containment switch is used to interrupt A/C compressor operation in the event of high
system discharge pressures.
zThe refrigerant containment switch is mounted on a Schrader- type valve fitting on the high
pressure side of the compressor manifold and tube assembly.
z A valve depressor, located inside the threaded end of the refrigerant containment switch,
presses on the Schrader valve stem.
z This allows the refrigerant containment switch to monitor the A/C compressor discharge
pressure.
z When the A/C compressor discharge pressure rises, the switch contacts open, disengaging the
A/C compressor. When the pressure drops, the contacts close to allow operation of the A/C
compressor. For additional information regarding operating pressure(s), refer to Section 412 -
00 .
z It is not necessary to discharge the refrigerant system to remove the refrigerant containment
switch.
Spring Lock Coupling Item Part Number Description
1 — Plastic indicator ring (part of 19D690) Klj . 8 ba
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