2003 FORD MUSTANG cooling

REMOVAL AND INSTALLATION
Transmission Fluid Cooler Tubes
Removal
1. Disconnect the battery cables.
2. Raise and support the vehicle. For additional information, refer to Section 100 - 02 .
3. Remove the nuts.
4. Remove the fluid cooler tube bracket at the engine.
5. NOTE: Use a backup wrench to hold the case fitting secure.
Remove the fluid cooler tubes at the transmission. Installation SECTION 307-
02: Transaxle/Transmission Cooling 2003 Mustang Workshop Manual Klj . 1 ba
32003 Mustang Workshop Manual
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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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Symptom Chart
Condition
Possible Sources Action
z Incorrect/erratic direction
of airflow from outlet(s) z
No vacuum to A/C heater
function switch selector.
z A/C heater function selector
switch leaks vacuum.
z Kinked/pinched vacuum hose.
z Leaking vacuum control
motor.
z Leaking A/C vacuum check
valve.
z Leaking A/C vacuum reservoir
tank and bracket.
z Vacuum actuator arm not
connected to door crank. z
Go To Pinpoint
Test A .
z Insufficient, erratic, or no
heat z
Low engine coolant level.
z Thermostat stuck open.
z Disengaged/damaged
temperature cable. z
Go To Pinpoint
Test B .
z The A/C does not
operate/does not operate
correctly z
CASS strategy failure.
z Open fuses.
z A/C clutch relay.
z Shorted blend door actuator.
z Powertrain control module.
z Circuitry short/open.
z A/C cycling switch damaged.
z A/C system discharged/low
charge.
z Function selector switch
damaged.
z A/C pressure cut-off switch
damaged.
z A/C compressor clutch
damaged. z
Go To Pinpoint
Test C .
z The A/C is always on zCircuitry short/open.
z A/C cycling switch.
z A/C heater function selector
switch.
z Constant control relay
module.
z Incorrect A/C clutch air gap. z
Go To Pinpoint
Test D .
z Insufficient A/C cooling zRestricted A/C evaporator
core orifice.
z Low refrigerant level. z
Go To Pinpoint
Test E .
z No operation in all the
temperature settings z
Damaged blend door actuator
cable.
z Damaged air temperature
control door. z
Go To Pinpoint
Test F .
z The blower motor does
not operate z
Open fuse.
z Circuitry open/shorted.
z Damaged heater blower
motor switch (18578).
z Damaged heater blower
motor switch resistor (18591).
z Damaged blower motor relay.
z Damaged blower motor. z
Go To Pinpoint
Test G .
z The blower motor
operates continuously in z
Circuitry short/open.
z Damaged heater blower z
Go To Pinpoint Klj . 6 ba
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PINPOINT TEST B: INSUFFICIENT, ERRATIC, OR NO HEAT z
Does the vacuum control motor hold a vacuum? A20 CHECK THE VACUUM CONTROL MOTOR INSTALLATION
z
Key in OFF position.
z Check the attachment of the vacuum control motor arm to
damper door.
z Is the vacuum control motor arm attached to the door or
door crank arm? Yes
REPAIR or INSTALL a
new damper door.
TEST the system for
normal operation.
No
CONNECT the vacuum
control motor arm to
the door and check
operation. TEST the
system for normal
operation.
Test Step Result / Action to Take
B1 CHECK FOR CORRECT ENGINE COOLANT LEVEL
z
Key in OFF position.
z Check the engine coolant level when hot and cold.
z Is the engine coolant at the correct level (hot/cold) as
indicated on the engine coolant recovery reservoir? Yes
GO to
B2 .
No
GO to B3 .
B2 CHECK FOR HOT WATER TO THE HEATER CORE INLET
HOSE WARNING: The heater core inlet hose will become
too hot to handle and may cause serious burns if the
system is working correctly.
z Key in START position.
z Allow the engine to reach normal operating temperature.
z Feel the heater core inlet hose. Yes
GO to
B4 .
No
TEST the engine cooling
system for correct
operation. REFER to
Section 303 - 03A or
Section 303 - 03B . Klj . 14 ba
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PINPOINT TEST C: THE A/C DOES NOT OPERATE/DOES NOT
OPERATE CORRECTLY z
Is the heater core inlet hose too hot to handle? B3 CHECK THE ENGINE COOLING SYSTEM INCLUDING
RADIATOR CAP FOR LEAKS z
Fill the engine cooling system to specified level.
z NOTE: It is not necessary to check the components
separately at this time.
z Pressure check the engine cooling system. Refer to Section 303 - 03A or
Section 303 - 03B .
z Does the engine cooling system, including the radiator
cap, hold pressure? Yes
GO to
B4 .
No
Pressure test the heater
core. REFER to
Component Tests, Heater
Core — Pressure Test. B4 CHECK THE HEATER CORE OUTLET HOSE FOR HOT
WATER z
Feel the heater core outlet hose.
z Is the heater core outlet hose cool or cold? Yes
TEST the heater core for a
plugged or partially
plugged condition. REFER
to
Section 303 - 03A or
Section 303 - 03B .
No
GO to Pinpoint Test E .
Test Step Result / Action to Take
C1 CHECK THE PCM PID WACF
z
Connect the diagnostic tool.
z Turn the function selector to the OFF position.
z Key in ON position.
z Enter the following diagnostic mode on the diagnostic
tool:
z Monitor the PCM PID WACF while turning the function
selector.
z Does the PCM PID WACF read YES? Yes
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual.
No
GO to
C2 .
C2 CHECK THE PCM PID WACF WITH THE A/C ON
z
Turn the function selector switch to the A/C position.
z Enter the following diagnostic mode on the diagnostic Yes
REFER to the Powertrain Klj . 15 ba
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PINPOINT TEST E: INSUFFICIENT A/C COOLING C294c-
3, circuit 348 (PK), harness side and ground.
z Is there voltage present? No
INSTALL a new function
selector switch. REFER to
Section 412
- 04 . TEST the
system for normal operation. D5 CHECK FOR A SHORTED CLUTCH INPUT
z
Key in OFF position.
z Disconnect: A/C Clutch C100.
z Key in ON position.
z Measure for voltage at the A/C clutch C100, circuit 347
(BK/YE), harness side and ground.
z Is there voltage present? Yes
INSTALL a new constant
control relay module. TEST the
system for normal operation.
No
CHECK the clutch air gap.
REFER to
Air Conditioning (A/C) Clutch Air Gap
Adjustment .
Test Step Result / Action to Take
E1 CHECK THE CENTER A/C REGISTER DISCHARGE
TEMPERATURE z
Carry out the refrigerant system tests. Refer to
Refrigerant System Tests in this section.
z Use the recorded data from the refrigerant system tests
to plot a vertical line for ambient temperature and a
horizontal line for center A/C register discharge
temperature.
z Is the intersection of the two lines within the upper
and lower limits? Yes
The tests indicate that the
system is functioning normally.
No
GO to
E2 . Klj . 25 ba
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to plot a vertical line for ambient temperature and a
horizontal line for A/C clutch OFF time in seconds.
z Is the intersection of the two lines above the upper
limit? DISCHARGE and RECOVER
the system to remove
excessive moisture or
refrigerant oil. REFER to
Air Conditioning (A/C) System
Recovery, Evacuation and
Charging . TEST the system
for normal operation.
No
GO to E7 .
E6 CHECK FOR A HIGH SUCTION PRESSURE
z
Refer to the data plot used to evaluate the system low
pressure performance in Step E3.
z Is the intersection of the two lines above the upper
limit? Yes
REMOVE the A/C evaporator
core orifice to repair missing or
damaged (leaking) O-
ring
seals. REFER to Section 412 -
03 . TEST the system for
normal operation.
No
INSTALL a new A/C cycling
switch when the intersection of
the two lines is below the
lower limit. REFER to Section 412 - 03 . TEST the system for
normal operation. E7 CHECK THE AMBIENT TEMPERATURE
z
Refer to the data plot used to evaluate the system A/C
clutch OFF time in Step E5.
z Is the ambient temperature above 26°C (80°F)? Yes
This is normal operation for
the refrigerant system in high
humidity conditions.
No
DISCHARGE and RECOVER
the system to correct an
overcharge condition. REFER
to
Air Conditioning (A/C) System Recovery, Evacuation
and Charging . TEST the
system for normal operation. E8 CHECK FOR A HIGH DISCHARGE PRESSURE
z
Refer to the data plot used to evaluate the system high
pressure performance in Step E2.
z Is the intersection of the two lines above the upper
limit? Yes
GO to
E9 .
No
GO to E11 .
E9 CHECK FOR A NORMAL LOW PRESSURE
z
Use the recorded data from the refrigerant system tests
to plot a vertical line for ambient temperature and a
horizontal line for compressor suction (low) pressure. Yes
REFER to
Section 303 - 03A or
Section 303 - 03B . to diagnose
the engine cooling system.
TEST the system for normal
operation. Klj . 27 ba
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Heater Core
WARNING: Carbon monoxide gas is colorless, odorless and dangerous. If it is necessary
to operate the engine with the vehicle in a closed area such as a garage, always use an exhaust
collector to vent the exhaust gases outside the closed area. Failure to follow these instructions
may result in personal injury.
1. NOTE: Testing of returned heater cores reveals that a large percentage of heater cores are
good and did not require installation of a new heater core. If a heater core leak is suspected, the
heater core must be tested by following the Plugged Heater Core Component Test before the
Heater Core Pressure Test. Carry out a system inspection by checking the heater system
thoroughly as follows:
Inspect for evidence of coolant leakage at the heater water hose to heater core attachments. A
coolant leak in the heater water hose could follow the heater core tube to the heater core and
appear as a leak in the heater core.
CAUTION: Spring- type clamps are installed as original equipment. Installation and
overtightening of non- specification clamps can cause leakage at the heater water hose
connection and damage the heater core.
2. Check the integrity of the heater water hose clamps.
Heater Core— Plugged
WARNING: The heater core inlet hose will become too hot to handle if the system is
working correctly.
1. Check to see that the engine coolant is at the correct level.
2. Start the engine and turn on the heater.
3. When the engine coolant reaches operating temperature, feel the heater core outlet hose to see if it is hot.
If it is not hot:
zthe heater core may have an air pocket.
z the heater core may be plugged.
z the thermostat is not working correctly.
Heater Core— Pressure Test
Use the radiator/heater core pressure tester to carry out the pressure test. 1. NOTE: Due to space limitations, a bench test may be necessary for pressure testing.
Drain the coolant from the cooling system. For additional information, refer to Section 303 - 03A
or
Section 303 - 03B .
2. Disconnect the heater water hoses from the heater core. For additional information, refer to Klj . 37 ba
412003 Mustang Workshop Manual
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