2003 FORD MUSTANG heater

Pressure Test
1. Turn the engine OFF.
2. WARNING: Never remove the pressure relief cap under any conditions while the
engine is operating. Failure to follow these instructions could result in damage to the
cooling system or engine and/or personal injury. To avoid having scalding hot coolant or
steam blow out of the cooling system, never remove the pressure relief cap from a hot
degas bottle. Wait until the engine has cooled, then wrap a thick cloth around the
pressure relief cap and turn it slowly one turn (counterclockwise). Step back while the
pressure is released from the cooling system. When certain all the pressure has been
released, remove the pressure relief cap (still with a cloth).
Check the intercooler coolant level. For additional information, refer to Supercharger Cooling System Draining, Filling and Bleeding in this section.
3. Connect the Radiator/Heater Core Pressure Tester to the degas bottle nipple. Install a pressure test pump to the quick- connect fitting of the test adapter.
4. NOTE: If the plunger of the pump is depressed too fast, an erroneous pressure reading will
result.
Slowly depress the plunger of the pressure test pump until the pressure gauge reading stops
increasing and note the highest pressure reading obtained.
5. If the pressure relief cap does not hold pressure, remove and wash the pressure relief cap in clean water to dislodge all foreign particles from the gaskets. Check the sealing surface in the
filler neck.
6. If 69 kPa (10 psi) cannot be reached, install a new pressure relief cap. If more than 12 kPa (18 psi) shows on the gauge, install a new pressure relief cap.
7. CAUTION: If the pressure drops, check for leaks at the intercooler hoses or other
system components and connections. Any leaks which are found must be corrected and
the system rechecked.
NOTE: Intercooler system is not connected to the main engine cooling system.
Pressurize the intercooler cooling system as described in Step 4 (using a pressure relief cap
that operates within the specified upper and lower pressure limits). Observe the gauge reading
for approximately two minutes; refer to General Specifications. Pressure should not drop during
this time. zIf the pressure drops and no external leak is found, the intercooler may be the cause.
Remove and inspect the intercooler. Install a new intercooler if necessary.
8. Release the system pressure by loosening the pressure relief cap. Check the coolant level and replenish, if necessary, with the correct coolant mixture. For additional information, refer to
Supercharger Cooling System Draining, Filling and Bleeding in this section.
Cap WARNING: Never remove the pressure relief cap under any conditions while the engine is Klj . 5 ba
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operating. Failure to follow these instructions could result in damage to the cooling system or
engine and/or personal injury. To avoid having scalding hot coolant or steam blow out of the
cooling system, use extreme care when removing the pressure relief cap from a hot degas
bottle. Wait until the engine has cooled, then wrap a thick cloth around the pressure relief cap
and turn it slowly one turn (counterclockwise). Step back while the pressure is released from
the cooling system. When certain all the pressure has been released, remove pressure relief
cap (still with a cloth).
1. Immerse the pressure relief cap in water and install it on the shallow filler neck of Radiator/Heater Core Pressure Tester and Radiator Cap Adapter, part of Radiator/Heater Core
Pressure Tester.
2. Immerse the filler neck seal in water and install it in the filler neck adapter.
3. Install the filler neck adapter with the filler neck seal to the Radiator Cap Adapter.
4. Connect the female quick- connect fitting of the pressure test pump to the male quick- connect
fitting of the filler neck adapter.
5. NOTE: If the plunger of the pump is depressed too fast, an erroneous pressure reading will
result.
Slowly depress the plunger of the pressure test pump until the pressure gauge reading stops
increasing and note the highest pressure reading obtained.
6. Release the pressure by turning the relief screw counterclockwise. Then tighten the pressure relief screw and repeat Step 6 (at least twice) to make sure the reading is repeatable within the
specifications of the pressure relief cap.
7. If the pressure test gauge readings are not within specifications, install a new pressure relief cap. If the pressure test gauge readings are within specifications, carry out the cooling system
pressure test.
Radiator Leak Test, Removed From the Vehicle CAUTION: Never leak test an aluminum radiator or intercooler in the same water that
copper/brass radiators are tested in. Flux and caustic cleaners may be present in the cleaning
tank and they will damage aluminum radiators and intercoolers.
NOTE: Clean the radiator or intercooler before leak testing to avoid contamination of tank.
1. Leak test the radiator or intercooler in clean water with 138 kPa (20 psi) air pressure. Klj . 6 ba
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REMOVAL AND INSTALLATION
Intake Manifold Runner Control (IMRC) Actuator —
3.8L
Removal and Installation 1. Disconnect the battery ground cable. For additional information, refer to Section 414 - 01 .
2. Drain the cooling system. For additional information, refer to Section 303 - 03A .
3. Remove the upper intake manifold. For additional information, refer to Section 303 - 01A .
4. Remove the fuel injector supply manifold. For additional information, refer to Section 303 - 04A .
5. Remove the coolant bypass tube. For additional information, refer to Section 303 - 03A .
6. Remove the bolt and heater water inlet tube at the back of the lower intake.
7. Remove the two stud bolts and one bolt. Position the actuator aside.
8. Disconnect the linkage and remove the actuator.
SECTION 303-
14: Electronic Engine Controls 2003 Mustang Workshop Manual Klj . 1 ba
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9.
NOTE: New plastic IMRC retainers must be installed any time an IMRC rod is removed.
NOTE: Before installing the IMRC actuator, be sure to rotate the motor driver plate until the
levers make contact with the set screws, then rotate the motor until the motor bracket bolt holes
line up with the tapped holes in the lower intake manifold.
NOTE: Discard O- ring and install a new O- ring on the heater inlet tube. Lubricate the O- ring
with engine coolant prior to installation.
To install, reverse the removal procedure. Klj . 2 ba
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DESCRIPTION AND OPERATION
Transmission Electronic Control System
The powertrain control module (PCM) and its input/output network control the following transmission
operations:
zShift timing
z Line pressure (shift feel)
z Torque converter clutch
The transmission control is separate from the engine control strategy in the PCM, although some of
the input signals are shared. When determining the best operating strategy for transmission operation,
the PCM uses input information from certain engine- related and driver-demand related sensors and
switches.
In addition, the PCM receives input signals from certain transmission- related sensors and switches.
The PCM also uses these signals when determining transmission operating strategy.
Using all of these input signals, the PCM can determine when the time and conditions are right for a
shift, or when to apply or release the torque converter clutch (TCC). It will also determine the best line
pressure needed to optimize shift feel. To accomplish this, the PCM uses hydraulic solenoids to control
transmission operation.
The following provides a brief description of each of the sensors and actuators used to control
transmission operation.
Powertrain Control Module (PCM)
The operation of the transmission is controlled by the powertrain control module (PCM). Many input
sensors provide information to the PCM. The PCM then controls actuators which determine
transmission operation.
Air Conditioning (A/C) Clutch
An electromagnetic clutch is energized when the clutch cycling pressure switch closes. The switch is
located on the suction accumulator/drier. The closing of the switch completes the circuit to the clutch
and draws it into engagement with the compressor driveshaft. When the A/C clutch is engaged,
electronic pressure control (EPC) is adjusted by the PCM to compensate for additional load on the
engine.
Brake Pedal Position (BPP) Switch
The brake pedal position (BPP) switch tells the PCM when the brakes are applied. The torque
converter clutch disengages when the brakes are applied. The BPP switch closes when the brakes are
applied and opens when they are released.
Engine Coolant Temperature (ECT) Sensor
The engine coolant temperature (ECT) sensor detects temperature of engine coolant and supplies the
information to the powertrain control module. The ECT sensor is used to control torque converter
clutch (TCC) operation. The ECT is installed in the heater outlet fitting or cooling passage on the
engine. For engine control applications, the ECT signal is used to modify ignition timing, EGR flow and
air- to-fuel ratio as a function of engine coolant temperature.
SECTION 307-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual Klj . 1 ba
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z
Refrigerant R- 134a must not be mixed with air for leak testing or used with air for any
other purpose above atmospheric pressure. R- 134a is combustible when mixed with high
concentrations of air and higher pressures.
z A number of manufacturers are producing alternative refrigerant products that are
designed to be used instead of R- 134a refrigerant. The use of any unauthorized
substitute refrigerant can severely damage the A/C components. If repair is required, use
only new or recycled refrigerant R- 134a.
CAUTION: To avoid contamination of the A/C system, always observe the following:
z Keep service tools and the work area clean.
z Never open or loosen a connection before discharging the system.
z When loosening a connection, if any residual pressure is evident, allow it to leak out
before opening the fitting.
z Evacuate a system that has been opened to install a new component or one that has
been discharged through leakage before charging.
z Seal an open fitting with a cap or plug immediately after disconnecting a component
from the system.
z Clean the outside of the fittings thoroughly before disconnecting a component from the
system.
z Do not remove the sealing caps from a new component until ready to install.
z Refrigerant oil will absorb moisture from the atmosphere if left uncapped. Do not open
an oil container until ready to use, and install the cap immediately after using. Store the
oil in a clean, moisture- free container.
z Install a new O- ring seal before connecting an open fitting. Coat the fitting and the O- ring
seal with refrigerant oil before connecting.
z When installing a refrigerant line, avoid sharp bends. Position the line away from the
exhaust or any sharp edges that can chafe the line.
z Do not open a refrigerant system or uncap a new component unless it is as close as
possible to room temperature. This will prevent condensation from forming inside a
component that is cooler than the surrounding air.
The manual climate control system heats or cools the vehicle depending on the function selector
switch position and the temperature selected.
zThe function selector switch position determines heating or cooling and air distribution.
z The temperature control setting determines the air temperature.
z The heater blower motor switch (18578) varies the blower motor speed.
Principles of Operation
There are four main principles involved with the basic theory of operation:
zheat transfer
z latent heat of vaporization
z relative humidity
z effects of pressure Heat Transfer Klj . 2 ba
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9 18591 Heater blower motor resistor Klj . 11 ba
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DIAGNOSIS AND TESTING
Climate Control System
Refer to Wiring Diagrams Cell
54 , Air Conditioner/Heater for schematic and connector information.
SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Special Tool(s)
Connector, Refrigerant
Pressure Line
412-
093 (T94P-19623- E) Set, A/C Fittings
412-
DS028 (014- 00333, D93L-
19703- B) or equivalent Vacuum Pump Kit
416-
D002 (D95L-7559- A) or
equivalent Breakout Box, EEC-V Control
System
418- 049 (014-00950, T94L-50-
EEC- V) Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent
diagnostic tool Pressure Test Kit
014-
R1072 or equivalent 77 III Automotive Meter
105-
R0056 or equivalent Klj . 1 ba
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