air conditioning FORD MUSTANG 2003 Workshop Manual

port. DISCARD the leaking
parts, and INSTALL a new
component.
z Vehicles with a
plastic intake
manifold. z
Acceptable condition. Some
plastic manifolds exhibit this
noise, which is the effect of
the plastic manifold.
z Automatic
transmission buzz or
hiss z
Incorrect
driveline
angles. z
CHECK for correct driveline
angles. REPAIR as
necessary. REFER to
Section 205 - 00 .
z Worn or
damaged main
control
solenoids or
valves. z
Using a transmission tester,
activate the solenoids to
duplicate sound. INSTALL
new components as
necessary. REFER to
Section 307 - 01 .
z Manual Transmission
Clutch throw- out
bearing whine. A
change in noise pitch
or loudness while
depressing the clutch
pedal z
Worn throw- out
bearing. z
INSTALL a new throw- out
bearing. REFER to Section 308 - 01 .
z Heating, vacuum and
air conditioning
(HVAC) system chirp
— most audible inside
the vehicle. Listen for
a change in noise
pitch or loudness
while changing the
HVAC system blower
speed z
Damaged or
worn HVAC
blower bearing. z
INSTALL a new blower
motor. REFER to Section 412 - 02 .
z Air conditioning (A/C)
clutch ticking —
occurs when the
compressor clutch
engages z
Acceptable
noise.
z Incorrect air
gap. z
LISTEN to the clutch to
determine if the noise occurs
with clutch engagement. A
small amount of noise is
acceptable. If the noise is
excessive, CHECK the A/C
clutch air gap. INSPECT the
A/C clutch for wear or
damage. INSTALL a new
clutch as necessary. REFER
to Section 412 - 03 .
z Intermittent rattle, or
scraping/rubbing
noise z
Loose exhaust
heat shield(s). z
INSPECT the exhaust
system for loose parts using
a glove or clamps to verify
cause. REPAIR as
necessary. REFER to
Section 309 - 00 .
z Wiring, hose or
other part
interfering with
accessory drive
belt or pulley. z
INSPECT accessory drive
system closely verifying
there is adequate clearance
to all rotating components.
REPAIR as necessary.
z Engine ticking or
knocking noise —
occurs during idle or z
Piston noise or
valvetrain noise
(bled down z
Go To Pinpoint Test G . Klj . 30 ba
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16.
CAUTION: The cap screw is hidden; make sure to remove it or the engine front
cover will be damaged.
NOTE: Record the location, type and size of the fasteners.
Remove the engine front cover. zSlide the engine front cover off the two dowels.
z Remove and discard the engine front cover gasket.
Installation 1. CAUTION: In order to prevent foreign material from contaminating the engine block
or the engine front cover it is necessary to seal the coolant and oil passages of both
components. Failure to follow these directions will result in engine damage.
CAUTION: Do not use a surface conditioning pad or any other type of fibrous
abrasive disc to clean the gasket surfaces. Failure to follow these directions will result in
engine damage.
Clean and inspect the engine block and front cover as follows:
zPack the exposed portion of the oil pan with clean shop towels.
z Plug the oil and coolant passages.
z Clean the gasket surfaces.
z Clean all surfaces requiring gasket sealant with metal surface cleaner.
z Using compressed air, remove any remaining foreign material from the engine block and
engine front cover.
z Remove the shop towels from the oil pan.
z Remove the plugs or seals from the engine block and engine front cover. Klj . 4 ba
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12 — Coolant reservoir bottle electrical connector
13 — Radio ignition interference capacitor electrical
connector
14 — Fuel injector electrical connectors
15 — Exhaust vacuum regulator (EVR) electrical
connector
16 — Differential pressure feedback EGR electrical
connector
17 — RH ignition coil electrical connectors
18 — Ignition coil electrical connectors
19 — Throttle position (TP) sensor electrical connector
20 — Idle air control (IAC) solenoid electrical connector
21 — Voltage regulator electrical connector
22 — Engine coolant temperature (ECT) electrical
connector
23 — Generator battery electrical connector
24 — Radio ignition interference capacitor electrical
connector
25 — Crankshaft position (CKP) sensor electrical
connector
26 — Air conditioning compressor clutch electrical
connector
27 — 16 pin electrical connector Klj . 3 ba
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19. Disconnect the transmission main control harness electrical connector.
20. Raise and support the vehicle. For additional information, refer to
Section 100 - 02 .
21. Disconnect the RH heated oxygen sensor (HO2S) electrical connector.
22. Disconnect the crankshaft position (CKP) sensor electrical connector.
23. Disconnect the air conditioning compressor electrical connector. Klj . 5 ba
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Component Tests
Drive Belt Noise/Flutter
Drive belt chirp occurs due to pulley misalignment or excessive pulley runout. It can be the result of a
damaged pulley or an incorrectly aligned pulley.
To correct, determine the area where the noise comes from. Check each of the pulleys in that area
with a straightedge to the crankshaft pulley, looking for accessory pulleys out of position in the fore/aft
direction or at an angle to the straightedge.
Drive belt squeal is an intermittent noise that occurs when the drive belt slips on a pulley during certain
conditions, such as: engine start up, rapid engine acceleration, or A/C clutch engagement.
Drive belt squeal can occur:
zif any of the accessories are damaged, have a worn or damaged bearing, internal torsional
resistance above normal. All accessories should be rotatable by hand in the unloaded condition.
If not, inspect the accessory.
z if fluid gets on the drive belt. This includes power steering fluid, engine coolant, engine oil or air
conditioning system lubricant. If fluid does get on the drive belt during service, clean the drive
belt with soap and water and thoroughly rinse with clean water.
z NOTE: The drive belt tensioner arm should rotate freely without binding.
if the drive belt is too long. A drive belt that is too long will allow the drive belt tensioner arm to
go all the way to the arm travel stop under certain load conditions, which will release tension to
the drive belt. If the drive belt tensioner indicator is outside the installation wear range window,
install a new drive belt.
z if the drive belt tensioner is worn or damaged.
Belt Tension
NOTE: Drive belt tension is not adjustable.
The drive belt tensioner automatically adjusts drive belt tension. Symptom Chart Condition
Possible Sources Action
z Drive belt
noise, chirping,
flutter z
Defective/worn drive
belt.
z Misaligned pulley.
z Pulley runout.
z Damaged
accessories.
z Fluid contamination
of drive belt. z
GO to Component Tests, Drive
Belt, Noise/Flutter.
z Damaged or worn
drive belt tensioner. z
GO to Component Tests, Belt
Tensioner, Automatic.
z Premature
drive belt wear z
Defective drive belt.
z Misaligned pulley.
z Pulley runout.
z Damaged
accessories.
z Incorrectly installed
drive belt. z
GO to Component Tests, Drive
Belt Noise/Flutter and Drive
Belt Misalignment diagnosis. 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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DIAGNOSIS AND TESTING
Visual Inspection
This inspection will identify modifications or additions to the vehicle operating system that may affect
diagnosis. Inspect the vehicle for non-
Ford factory add-on devices such as:
z electronic add- on items:
„ air conditioning
„ generator (alternator)
„ engine turbo
„ cellular telephone
„ cruise control
„ CB radio
„ linear booster
„ backup alarm signal
„ computer
z Vehicle modification:
These items, if not installed correctly, will affect the powertrain control module (PCM), or transmission
function. Pay particular attention to add- on wiring splices in the PCM harness or transmission wiring
harness, abnormal tire size, or axle ratio changes.
zLeaks; refer to Leak Inspection.
z Correct linkage adjustments; refer to Section 307 - 05 .
Shift Linkage Check
Check for a misadjustment in shift linkage by matching the detents in the transmission range selector
lever with those of the manual lever in the transmission. If they match, the misadjustment is in the
indicator. Do not adjust the shift linkage.
Hydraulic leakage at the manual control valve can cause delay in engagements and/or slipping while
operating if the linkage is not correctly adjusted. Refer to Section 307 - 05 for shift linkage adjustment.
Check TSBs and OASIS
Refer to all technical service bulletins (TSB) and OASIS messages which pertain to the transmission
concern and follow the procedure as described.
Carry Out On- Board Diagnostics (KOEO, KOER)
After a road test, with the vehicle warm and before disconnecting any connectors, carry out the Quick
Test using the scan tool. Refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual. SECTION 307-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual Klj . 1 ba
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DESCRIPTION AND OPERATION
Climate Control System
WARNING: To avoid accidental deployment and possible injury, the air bag system
backup power supply must be depleted before repairing any climate control components. To
deplete the backup power supply, disconnect the battery ground cable and wait one minute.
Failure to follow these instructions may result in personal injury.
WARNING: Carbon monoxide 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.
WARNING: R- 134a is classified as a safe refrigerant, but misuse can make it dangerous.
The following precautions must be observed:
zAlways wear safety goggles when repairing an air conditioning system.
z Avoid contact with liquid refrigerant R- 134a. R-134a vaporizes at approximately - 25°C (-
13°F) under atmospheric pressure and it will freeze skin tissue.
z Never allow refrigerant R- 134a gas to escape in quantity in an occupied space. R- 134a is
non- toxic, but it will displace the oxygen needed to support life.
z Never use a torch in an atmosphere containing R- 134a gas. R-134a is non-toxic at all
normal conditions, but when it is exposed to high temperatures, such as a torch flame, it
decomposes. During decomposition it releases irritation and toxic gases (as described in
the MSDS sheet from the manufacturer). Decomposition products are hydrofluoric acid,
carbon dioxide and water.
z Do not allow any portion of the charged air conditioning system to become too hot. The
pressure in an air conditioning system rises as the temperature rises and temperatures
of approximately 85°C (185°F) can be dangerous.
z Allow the engine to cool sufficiently prior to carrying out maintenance or serious burns
and injury can occur.
CAUTION: To avoid damaging the vehicle or A/C components, the following precautions
must be observed:
zThe A/C refrigerant of all vehicles must be identified and analyzed prior to refrigerant
charging. Failure to due so can contaminate the shop bulk refrigerant and other vehicles.
z Do not add R- 12 refrigerant to an A/C system that requires the use of R- 134a refrigerant.
These two types of refrigerant must never be mixed. Doing so can damage the A/C
system.
z Charge the A/C system with the engine running only at the low- pressure side to prevent
refrigerant slugging from damaging the A/C compressor.
z Use only R- 134a refrigerant. Due to environmental concerns, when the air conditioning
system is drained, the refrigerant must be collected using refrigerant recovery/recycling
equipment. Federal law REQUIRES that R- 134a be recovered into appropriate recovery
equipment and the process be conducted by qualified technicians who have been
certified by an approved organization, such as MACS, ASI etc. Use of a recovery machine
dedicated to R- 134a is necessary to reduce the possibility of oil and refrigerant
incompatibility concerns. Refer to the instructions provided by the equipment manufacturer when removing refrigerant from or charging the air conditioning system. SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Klj . 1 ba
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If two substances of different temperature are placed near each other, the heat in the warmer
substance will transfer to the colder substance.
Latent Heat of Vaporization
When a liquid boils (converts to a gas), it absorbs heat without raising the temperature of the resulting
gas. When the gas condenses (reverts back to a liquid), it gives off heat without lowering the
temperature of the resulting liquid.
Relative Humidity
The amount of moisture (water vapor content) that the air can hold is directly related to the air
temperature. The more heat there is in the air, the more moisture the air can hold. The lower the
moisture content in the air, the more comfortable you feel. Removing moisture from the air lowers its
relative humidity and improves personal comfort.
Effects of Pressure on Boiling or Condensation
As the pressure is increased on a liquid, the temperature at which the liquid boils (converts to a gas)
also increases. Conversely, when the pressure on a liquid is reduced, its boiling point is also reduced.
When in the gas state, an increase in pressure causes an increase in temperature, while a decrease in
pressure will decrease the temperature of the gas.
Compressor Anti-
Slugging Strategy
Liquid refrigerant may accumulate in the A/C compressor under certain conditions. To alleviate
damage to the A/C compressor, compressor anti- slugging strategy (CASS) is utilized.
CASS is initiated only under specific conditions:
zthe ignition is off for more than 8 hours
z the ambient temperature is above -4º C (25ºF)
z battery voltage is above 8.5 volts during engine cranking
When these conditions are present, the powertrain control module (PCM) will activate the A/C control
relay prior to cranking of the engine. The A/C control relay engages the A/C compressor for
approximately 4- 15 A/C compressor revolutions or a maximum of 2 seconds (depending upon vehicle
application), allowing the liquid refrigerant to be pushed from the A/C compressor. CASS is initiated by
the PCM regardless of the function selector switch position or the EATC system settings.
The Refrigerant Cycle
During stabilized conditions (air conditioning system shut down), the refrigerant is in a vaporized state
and pressures are equal throughout the system. When the A/C compressor (19703) is in operation, it
increases pressure on the refrigerant vapor, raising its temperature. The high- pressure and high-
temperature vapor is then released into the top of the A/C condenser core (19712).
The A/C condenser core, being close to ambient temperature, causes the refrigerant vapor to
condense into a liquid when heat is removed from the refrigerant by ambient air passing over the fins
and tubing. The now liquid refrigerant, still at high pressure, exits from the bottom of the A/C
condenser core and enters the inlet side of the A/C evaporator core orifice (19D990).
The A/C evaporator core orifice is the restriction in the refrigerant system that creates the high
pressure buildup upstream of the A/C evaporator core (19860) and separates the high and low
pressure sides of the A/C system. As the liquid refrigerant leaves this restriction, its pressure and
boiling point are reduced.
The liquid refrigerant is now at its lowest pressure and temperature. As it passes through the A/C Klj . 3 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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