2003 FORD MUSTANG check engine light

3.
NOTE: Running this test with the vehicle in gear or with the A/C compressor clutch engaged
(running) will cause incorrect diagnosis.
Place the transmission in PARK (P) or NEUTRAL (N).
4. Start the engine and allow the engine to idle throughout this test. Allow the engine to run for 2 minutes, then record the ECT (4.6L) or CHT (3.8L) voltage. Record the ECT (4.6L) or CHT
(3.8L) voltage every 60 seconds. When the ECT (4.6L) or CHT (3.8L) voltage trend changes
direction or only changes slightly (0.03 volts or less) from the previous reading, record this as
the thermostat opening voltage. Use the voltage and corresponding coolant temperature chart
listed below for 4.6L engines only.
5. If the thermostat opening voltage is greater than 0.75 volts and less than 82°C (180°F), install a new water thermostat.
6. If the thermostat opening voltage is less than 0.75 volts and greater than 82°C (180°F), the water thermostat is good and a new water thermostat should not be installed. GO to Symptom Chart for further instructions.
Thermostat — Mechanical Test
1. Remove the water thermostat.
2. Check the water thermostat for seating. Hold the water thermostat up to a lighted background. Leakage of light around the thermostat valve at room temperature indicates that a new water
thermostat should be installed. Some water thermostats have a small leakage notch at one
location on the perimeter of the thermostat valve, which is considered normal.
3. Immerse the water thermostat in a boiling coolant and water mixture.
4. See the General Specifications chart for water thermostat opening temperatures.
Radiator Leak Test, Removed From the Vehicle CAUTION: Never leak test an aluminum radiator 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.
NOTE: Always install plugs in the oil cooler fittings before leak- testing or cleaning any radiator.
NOTE: Clean the radiator before leak- testing to avoid contamination of tank. Coolant Temperature °C (°F) ECT (Volts)
22 (71) 3.00
43 (109) 2.01
71 (159) 1.01
82 (180) 0.75
91 (195) 0.059
97 (206) 0.050
105 (221) 0.040 Klj . 9 ba
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CAUTION: Some vehicle cooling systems are filled with Motorcraft Premium Engine
Coolant VC -4-A (in Oregon VC- 5, in Canada CXC- 10) or equivalent meeting Ford specification
ESE- M97B44- A (green color). Others are filled with Motorcraft Premium Gold Engine Coolant
VC -7-A or equivalent meeting Ford specification WSS- M97B51-A1 (yellow color). Always fill the
cooling system with the same coolant that is present in the system. Do not mix coolant types.
NOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC- 6, darkens Motorcraft
Premium Gold Engine Coolant from yellow to golden tan.
1. Verify the customer's concern by operating the engine to duplicate the condition.
2. Inspect to determine if any of the following mechanical or electrical concerns apply.
3. If the inspection reveals an obvious concern that can be readily identified, repair it as necessary.
4. Inspect the coolant condition. 1. WARNING: Never remove the pressure relief cap while the engine is
operating or when the cooling system is hot. Failure to follow these instructions
can result in damage to the cooling system or engine or personal injury. To avoid
having scalding hot coolant or steam blow out of the degas bottle when removing
the pressure relief cap, wait until the engine has cooled, then wrap a thick cloth
around the pressure relief cap and turn it slowly. Step back while the pressure is
released from the cooling system. When you are sure all the pressure has been
released, (still with a cloth) turn and remove the pressure relief cap.
Allow the engine to cool. Once pressure is released, remove the pressure relief cap.
2. CAUTION: Check the coolant and engine oil level and top off the coolant if
needed. If there is engine coolant in the engine oil the cause must be corrected
and oil/fluid changed or major component damage can occur.
CAUTION: Some vehicle cooling systems are filled with Motorcraft Premium
Engine Coolant VC -4-A (in Oregon VC- 5, in Canada CXC- 10) or equivalent meeting
Ford specification ESE- M97B44-A (green color). Others are filled with Motorcraft
Premium Gold Engine Coolant VC -7-A or equivalent meeting Ford specification
WSS- M97B51- A1 (yellow color). Always fill the cooling system with the same
coolant that is present in the system. Do not mix coolant types.
Inspect the coolant color:
„If Motorcraft Premium Engine Coolant (green color) VC-4- A or equivalent meeting
Ford specification ESE-M97B44- A has a clear, light green or blue color, this Visual Inspection Chart
Mechanical Electrical
z
Radiator brackets
z Leaks
z Damaged hoses
z Hose clamps
z Water pump
z Radiator
z Degas bottle
z Water pump bracket z
Damaged water pump wiring Klj . 2 ba
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indicates higher water content than required.
„ NOTE: The addition of Motorcraft Cooling System Stop Leak Pellets, VC- 6,
darkens Motorcraft Premium Gold Engine Coolant from yellow to golden tan.
If Motorcraft Premium Gold Engine Coolant (yellow color) VC-7- A or equivalent
meeting Ford specification WSS- M97B51-A1 has a clear or pale yellow color, this
indicates higher water content than required.
„ Dark brown can indicate unauthorized stop leak may have been used. Use
Motorcraft Cooling System Stop Leak Pellets VC- 6 or equivalent meeting Ford
specification ESE-M99B37- 5 except as noted in ES-F65E-19A511- AA only.
„ A light or reddish brown color indicates that rust may be present in the cooling
system. Flush the system and refill with the correct mixture of water and engine
coolant.
„ An iridescent sheen on top of the coolant or a milky brown color can indicate a
trace of oil is entering the system. For additional information on engine diagnosis,
refer to Section 303 - 00 .
3. If the engine coolant appearance is acceptable, test the engine coolant freezing point
range with the special tool. The freezing point should be in the range - 50°F to -10°F. If
the vehicle is driven in cold climates less than - 34°F, it may be necessary to increase the
coolant concentration to get adequate freeze protection.
„Maximum coolant concentration is 60/40.
„ Minimum coolant concentration is 40/60.
4. Check the coolant system conditions:
„If the intercooler fluid is low, add the specified coolant mixture only.
„ If the intercooler coolant fluid tests weak, add straight engine coolant until the
readings are within acceptable levels.
„ If the engine coolant tests strong, remove some of the engine coolant and add
water until readings are within acceptable levels.
5. If the concern remains after the inspection, determine the symptom(s). GO to Symptom Chart .
6. Verify the cooling system is correctly filled and bled. Refer to Supercharger Cooling System Draining, Filling and Bleeding in this section.
Symptom Chart
Pinpoint Tests PINPOINT TEST A: LOSS OF COOLANT SYMPTOM CHART
Condition
Possible Sources Action
z Loss of intercooler
coolant z
Intercooler.
z Intercooler
radiator.
z Water pump.
z Coolant hoses.
z Degas bottle. z
Go To Pinpoint Test A . Klj . 3 ba
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10. If the vehicle stalls in (D) or manual 2 at idle with vehicle at a stop, move the transmission range
selector lever to manual 1 position. If the vehicle stalls, see torque converter operation
concerns. For additional information, refer to Diagnosis By Symptom in this section. If the
vehicle does not stall in (D), refer to Diagnosis By Symptom in this section.
11. If the vehicle exhibits a vibration during the road test, complete the Road Test Evaluation Form. This form will aid the technician in determining the source of the vibration.
NOTE: The following is a list of common vehicle concerns that have been misdiagnosed as torque
converter clutch shudder. For diagnosis of the following items refer to the appropriate sections of the
workshop manual and the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
zspark plugs - check for cracks, high resistance or broken insulators
z plug wires
z fuel injector - filter may be plugged
z fuel contamination - poor engine performance
z EGR valve - valve may let in too much exhaust gas and cause engine to run lean
z vacuum leak - engine will not get correct air/fuel mixture
z MAP/MAF sensor - incorrect air/fuel mixture
z HO2S sensor - too rich/lean air/fuel mixture
z fuel pressure - may be too low
z engine mounts - loose/damaged mounts can cause vibration concerns
z axle joints - check for vibration Torque Converter Road Evaluation Form
1) Does the Torque Converter
Engage/Disengage? Yes ·
GO to Step 2. No ·
REFER to Diagnosis By Symptom —
Torque Converter No Apply Routine
240/340 and Always Applied Routine
241/341 in this section for further
diagnosis information. Repair as
required, verify converter operation
and then continue. 2) Does vibration occur during 3-
4 or 4-3 shift at:
light, medium, or heavy throttle? Light ·
May be torque converter clutch
shudder. GO to Step 3. Medium ·
May be torque converter clutch
shudder. GO to Step 3. Heavy ·
Not torque converter clutch shudder
— converter does not engage due to
PCM strategy. REFER to Section 100 - 04 and
Diagnosis By Symptom —
Noise/Vibration Routine 254/354
in this section for further diagnosis. 3) Is the problem vehicle speed dependent Yes ·
Not torque converter clutch shudder Klj . 2 ba
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DIAGNOSIS AND TESTING
Transmission Drive Cycle Test
NOTE:
Always drive the vehicle in a safe manner according to driving conditions and obey all traffic
laws.
NOTE: The Transmission Drive Cycle Test must be followed exactly. Malfunctions must occur four
times consecutively for shift error DTC code to be set, and five times consecutively for continuous TCC
code to set.
NOTE: When carrying out the Transmission Drive Cycle Test, refer to the Solenoid Application Chart
for correct solenoid operation.
After carrying out the Quick Test, use the Transmission Drive Cycle Test for checking continuous
codes.
1. Record and then erase Quick Test codes.
2. Warm engine to normal operating temperature.
3. Make sure transmission fluid level is correct.
4. With transmission in OVERDRIVE, moderately accelerate from stop to 80 km/h (50 mph). This allows the transmission to shift into fourth gear. Hold speed and throttle open steady for a
minimum of 15 seconds.
5. With transmission in fourth gear and maintaining steady speed and throttle opening, lightly apply and release brake to operate stoplamps. Then hold speed and throttle steady for a
minimum of five seconds.
6. Brake to a stop and remain stopped for a minimum of 20 seconds.
7. Repeat steps 4 through 6 at least five times.
8. Carry out Quick Test and record continuous DTCs. zIf the DTCs are still present, refer to the Diagnostic Trouble Code Chart. Repair all non
transmission DTCs first as they can directly affect the operation of the transmission.
Repeat the Quick Test and the Road Test to verify the correction. Erase the DTCs, carry
out the Drive Cycle Test and repeat the Quick Test after completing repair on the DTC.
z If the continuous test passes and a concern is still present, refer to Diagnosis By Symptom in this section, OASIS messages, and TSBs for concerns.
After On- Board Diagnostic
NOTE: The vehicle wiring harness, PCM and non- transmission sensors may affect transmission
operations. Repair these concerns first.
After the on- board diagnostic procedures are completed, repair all DTCs.
Begin with non- transmission related DTCs, then repair any transmission related DTCs. Use the
diagnostic trouble code chart for information on condition and symptoms. This chart will be helpful in
referring to the correct manual(s) and aids in diagnosing internal transmission concerns and external
non- transmission inputs. The pinpoint tests are used in diagnosing transmission electrical concerns.
Make sure that the vehicle wiring harness and the PCM are diagnosed as well. The Powertrain SECTION 307-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual Klj . 1 ba
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following areas of possible leakage should also be checked to determine if engine oil leakage is
causing the concern.
a. Leakage at the engine valve cover gasket may allow oil to flow over the torque converter housing or seep down between the torque converter housing and cylinder block causing oil to
be present in or at the bottom of the torque converter housing.
b. Oil galley plug leaks will allow oil to flow down the rear face of the cylinder block to the bottom of the torque converter housing.
c. Leakage at the crankshaft rear oil seal will work back to the flexplate, and then into the torque converter housing.
d. Leakage at engine oil pressure sensor.
Leak Check Test 1. Remove the fluid level indicator and note the color of the fluid. Original factory fill fluid is dyed red to aid in determining if leakage is from the engine or transmission. Unless a considerable
amount of makeup fluid has been added or the fluid has been changed, the red color should
assist in pinpointing the leak.
2. Remove the torque converter housing cover. Clean off any fluid from the top and bottom of the torque converter housing, front of the case and rear face of the engine and oil pan. Clean the
torque converter area by washing with a suitable nonflammable solvent and blow dry with
compressed air.
3. Wash out the torque converter housing, the front of the flexplate and the converter drain plugs. The torque converter housing may be washed out using cleaning solvent and a squirt- type oil
can. Blow all washed areas dry with compressed air.
4. Start and run the engine until the transmission reaches its normal operating temperature. Observe the back of the cylinder block and top of the torque converter housing for evidence of
fluid leakage. Raise the vehicle on a hoist; refer to Section 100 - 02 and run the engine at fast
idle, then at engine idle, occasionally shifting to the Overdrive and Reverse ranges to increase
pressure within the transmission. Observe the front of the flexplate, back of the cylinder block
(in as far as possible), and inside the torque converter housing and front of the case. Run the
engine until fluid leakage is evident and the probable source of leakage can be determined.
Leak Check Test With Black Light Used With 12 Volt Master UV Diagnostic Inspection Kit
Oil soluble aniline or fluorescent dyes premixed at the rate of 2.5ml (1/2 teaspoon) of dye powder to
0.235L (1/2 pint) of transmission fluid have proved helpful in locating the source of fluid leakage. Such
dyes may be used to determine whether an engine oil or transmission fluid leak is present, or if the
fluid in the fluid cooler leaks into the engine cooling system. A black light must be used with the
fluorescent dye solution. Klj . 4 ba
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PINPOINT TEST D: CLUTCH PEDAL PULSATION clutch disengaged and engine idling, move
the shift lever to a position halfway between
REVERSE and NEUTRAL.
z Slowly engage clutch. The transmission will
behave as if it is in NEUTRAL.
z Gear clash can now be heard if an attempt
is made to shift into REVERSE with the
clutch engaged. Reserve can now be
measured.
z While maintaining light pressure on the shift
selector, slowly press the clutch pedal to the
floor. The gear clash will stop and the shift
selector will slide into the REVERSE
position.
z Is there a minimum 19.05 mm (0.750 inch)
clutch pedal reserve? CHECK the clutch pressure plate and clutch
disc. INSTALL a new clutch pressure plate
or clutch disc if necessary. REFER to
Section 308
- 01 . TEST the system for
normal operation. Test Step Result / Action to Take
D1 CHECK THE CLUTCH PEDAL
PULSATION z
Key in START position.
z With the transmission in NEUTRAL,
slowly press the clutch pedal.
z Does the clutch pedal pulsate while
being pressed? Yes
GO to
D2 .
No
VERIFY customer concern. GO to Symptom Chart if necessary.
D2 INSPECT PRESSURE PLATE BOLTS
z
Inspect the pressure plate- to-flywheel
bolts.
z Are any of the pressure plate- to-
flywheel bolts loose? Yes
TIGHTEN or INSTALL new bolts. REFER to
Section 308
- 01 . TEST the system for normal
operation.
No
GO to D3 .
D3 INSPECT THE CLUTCH PRESSURE
PLATE z
Remove the clutch pressure plate.
Refer to Section 308 - 01 .
z INSPECT the clutch pressure plate for
damage. Refer to Pressure Plate Check .
z Are there any signs of damage
present on the clutch pressure plate? Yes
INSTALL a new clutch pressure plate. REFER
to
Section 308 - 01 . TEST the system for normal
operation.
No
GO to D4 .
D4 INSPECT THE CLUTCH DISC
z
Carry out the clutch disc inspection
procedure. Refer to Disc Check .
z Is the clutch disc OK? Yes
GO to
D5 .
No
INSTALL a new clutch disc. REFER to Section 308 - 01 . TEST the system for normal operation.
D5 INSPECT THE FLYWHEEL Klj . 9 ba
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DESCRIPTION AND OPERATION
Fuel Tank And Lines
WARNING: Do not smoke, carry lighted tobacco or an open flame of any type when
working on or near any fuel- related component. Highly flammable mixtures are always present
and may be ignited, possibly resulting in personal injury.
The vehicle utilizes a returnless fuel system consisting of:
zthe fuel tank.
z a fuel tank filler pipe which contains a restrictor plate to permit only unleaded fuel to be pumped
into the fuel tank.
z a 1/8 turn fuel tank filler cap.
z a fuel filter providing filtration to protect the fuel injectors.
z a single fuel line accommodating the returnless fuel system.
z a fuel injection supply manifold which contains a differential pressure sensor and a fuel
temperature sensor.
z a fuel pump and sender assembly which provides pressurized fuel to the engine and contains:
„an inlet filter.
„ a check valve which maintains system pressure after the pump is shut off.
„ a pressure relief valve for overpressure protection in the event of restricted flow.
The fuel pump is controlled by an electronic fuel pump driver module which is enabled by the
powertrain control module (PCM). Electrical power to the fuel pump is provided through the inertia fuel
shutoff (IFS) switch, which is located in the luggage compartment. SECTION 310-
01: Fuel Tank and Lines 2003 Mustang Workshop Manual Klj . 1 ba
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