cooling FORD MUSTANG 2003 Workshop Manual

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-
03: Air Conditioning 2003 Mustang Workshop Manual Klj . 1 ba
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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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DESCRIPTION AND OPERATION
Control Components
Manual A/C
The climate control system heats or cools the vehicle interior depending on the function selector
position and the temperature selected. Function selector position determines heating or cooling and air
distribution. The temperature blend control setting determines air temperature.
The manual climate control components are used to:
zselect air inlet source (outside or recirculated).
z select blower motor speed.
z select discharge air temperature (temperature blend).
z select discharge air location (defrost, panel, floor).
z select A/C compressor clutch operation. Component Locations SECTION 412-
04: Control Components 2003 Mustang Workshop Manual Klj . 1 ba
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z
air bag warning indicator
z BRAKE warning indicator
z charging system indicator
z fail safe cooling warning indicator
z low coolant level indicator
z low fuel warning indicator
z traction control indicator
Instrument Cluster Replacement
When it is necessary to install a new instrument cluster, contact the Instrument Cluster Program.
Gauge Indication Systems
Tachometer
Engine rpm information is relayed to the instrument cluster from the powertrain control module (PCM)
over the standard corporate protocol (SCP) network.
Speedometer
The instrument cluster receives the vehicle speed signal from the PCM over the SCP network and
displays it on the speedometer gauge. If the instrument cluster receives no vehicle speed signal after
one second, the speedometer defaults to 0.0 km/h (0.0 mph).
Odometer
The instrument cluster receives an odometer message from the PCM and stores the mileage in
memory. When the instrument cluster fails to receive the odometer message for more than two
seconds, the odometer will display dashes.
Fuel Gauge
The fuel sender is hardwired to the fuel gauge. When the instrument cluster fails to receive the fuel
level signal for more than 33 seconds, the fuel level gauge will move below E (empty). If the fuel level
signal operates correctly for more than 33 seconds, the fuel gauge will return to the correct position.
Fuel fills of less than 9.5 liters (2.5 gallons) require at least 10 minutes to update the fuel gauge
indication.
Engine Coolant Temperature Gauge
Engine coolant temperature information is received by the instrument cluster from the PCM over the
SCP network. Engine coolant temperatures above 121°C (250°F) will cause the gauge to indicate
above the normal band. If the engine coolant temperature information is missing or invalid for five
seconds, the temperature gauge will indicate below the cold (C) position.
Voltage Gauge (except Cobra)
The voltage gauge displays the system voltage as measured at the instrument cluster run input. Boost Gauge (Cobra only) Klj . 2 ba
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Pinpoint Tests
CAUTION: Do not make jumper connections except as directed. Incorrect connections
may damage the voltage regulator test terminals, fuses, or fuse links.
CAUTION: Do not allow any metal object to come in contact with the generator housing
and internal diode cooling fins.
NOTE: All voltage measurements are referenced to the negative (- ) battery post unless otherwise
specified. PINPOINT TEST A: BATTERY IS DISCHARGED OR VOLTAGE IS Symptom Chart
Condition
Possible Sources Action
z Battery is discharged or voltage is
low z
Circuitry.
z High key- off current
drain(s).
z Battery.
z Generator. z
Go To Pinpoint
Test A .
z The charging system warning
indicator is on with the engine
running (the system voltage does
not increase) z
Circuitry.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test B .
z The system overcharges (the
battery voltage is greater than 15.5
volts) z
Circuitry.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test C .
z The charging system warning
indicator is on with the engine
running and the battery increases
voltage z
Circuitry.
z Instrument cluster.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test D .
z The charging system warning
indicator is off with the ignition
switch in the RUN position and the
engine off z
Bulb.
z Circuitry.
z Instrument cluster.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test E .
z The charging system warning
indicator flickers or is intermittent z
Central junction box
(CJB) fuse 5 (15A).
z Generator
connector
unplugged (C102a).
z Circuitry.
z Generator. z
Go To Pinpoint
Test F .
z The generator is noisy zBolts or brackets.
z Drive belt.
z Generator or pulley. z
Go To Pinpoint
Test G .
z Radio interference zGenerator.
z Circuitry.
z In-vehicle
entertainment
system. z
Go To Pinpoint
Test F . Klj . 4 ba
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8. If the draw is found to be excessive, pull fuses from the battery/central junction box one at a
time and note the current drop. Do not reinstall the fuses until you are finished testing.
9. Check the wiring schematic in the wiring diagram for any circuits that run from the battery without passing through the battery/central junction box. Disconnect these circuits if the draw is
still excessive.
Battery— Electronic Drains Which Shut Off When the Battery Cable is Disconnected
1. Repeat the steps of the battery drain testing.
2. Make sure all doors are closed and accessories are off. Without starting the engine, turn the ignition switch to RUN for a moment and then OFF. Wait a few minutes for the illuminated entry
lamps to turn off if equipped.
3. Connect the ammeter and read the amperage draw.
The current reading (current drain) should be less than 50 mA (0.05 amp). If the current drain exceeds
50 mA (0.05 amp) after a few minutes, and if this drain did not show in previous tests, the drain is most
likely caused by an inoperative electronic component. As in previous tests, remove the fuses from the
battery/central junction box one at a time to locate the problem circuit.
Generator On- Vehicle Tests
CAUTION: To prevent damage to the generator, do not make jumper wire connections
except as directed.
CAUTION: Do not allow any metal object to come in contact with the housing and the
internal diode cooling fins with key on or off. A short circuit will result and burn out the diodes.
NOTE: Battery posts and cable clamps must be clean and tight for accurate meter indications.
NOTE: Refer to the Battery Tester Procedure Manual for complete directions for testing the charging
system.
1. Turn off all lamps and electrical components.
2. Place the vehicle in transmission range NEUTRAL and apply the parking brake.
3. Carry out the Load Test and No- Load Test according to the following component tests:
Generator On- Vehicle Tests— Load Test
1. Switch the battery tester to the ammeter function.
2. Connect the positive and negative leads of the battery tester to the corresponding battery terminals.
3. Connect the current probe to the generator B+ output terminal, circuit 38 (BK/OG). Klj . 12 ba
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4. Place the air bag module on a flat surface in an open outdoor area with the trim cover facing
upward.
5. Remain at least 6.1 meters (20 feet) away from the air bag module.
6. Deploy the air bag module by touching the other ends of the two wires to the terminals of a 12– volt battery.
7. To allow for cooling, wait at least ten minutes before approaching the deployed air bag.
8. Dispose of the deployed air bag module in the same manner as any other part to be scrapped. Klj . 2 ba
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4. Place the air bag module on a flat surface in an open outdoor area with the deflector can facing
downward.
5. Remain at least 6.1 meters (20 feet) away from the air bag module.
6. Deploy the air bag module by touching the other ends of the two wires to the terminals of a 12– volt battery.
7. To allow for cooling, wait at least ten minutes before approaching the deployed air bag.
8. Dispose of the deployed air bag module in the same manner as any other part to be scrapped. Klj . 2 ba
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