check engine light FORD MUSTANG 2003 Owner's Manual

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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provide ventilation.
WARNING: When lifting a plastic- cased battery, excessive pressure on the end walls
could cause acid to spew through the vent caps resulting in personal injury, damage to the
vehicle or to the battery. Lift with a battery carrier or with your hands on opposite corners.
1. Verify the customer concern by operating the engine to duplicate the concern.
2. Inspect the charging system (battery, generator cable, harness connectors, connections) to determine if any obvious mechanical or electrical concerns exist. If found, repair as necessary
and test the system for normal operation. Refer to the following tables:
3. Check the operation of the charging system warning indicator lamp (instrument cluster). Normal operation is as follows:
zWith the ignition switch OFF, the charging system warning indicator should be OFF.
z With the ignition switch in RUN and the engine off, the charging system warning indicator
light should be on.
z With the engine running, the charging system warning indicator light should be off.
4. Verify the battery is being charged. Carry out the Battery— Load Test. Refer to Component
Tests in this section.
5. If the customer concern is verified after the initial inspection, refer to the Symptom Chart to determine which tests to carry out.
Symptom Chart Visual Inspection Chart
Mechanical Electrical
z
Battery case, posts, hold- down clamp, cables and
connections
z Generator drive (serpentine) belt for condition and
tension. Refer to Section 303 - 05 .
z Generator pulley z
Battery junction box (BJB)
fuse 20 (20A)
z Fuse links
z Circuitry
z Battery charge warning
indicator
z Cables
Normal Charging System Voltages Ignition
Switch
Position A Circuit
36
(YE/WH) I Circuit
904
(LG/RD) Generator B+
Circuit 38 (BK/OG) Battery Engine to
battery
ground Charging
System Warning Indicator
Operation OFF 12V 0V 12V 12V 0V Off
RUN-
engine off 12V 1-
3V 12V 12V 0V Illuminated
RUN-
engine
running 13-
15V 13-
15V 13-
15V 13-15V 0V Off Klj . 3 ba
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PINPOINT TEST H: RADIO INTERFERENCE
Component Tests
Battery—Load Test
1. With the engine running, turn the A/C on, the blower motor on high speed and the headlamps on high beam.
2. Increase the engine speed to approximately 2,000 rpm. The voltage should increase a minimum of 0.5 volt above the base voltage.
zIf the voltage does not increase as specified, carry out the Generator On- Vehicle Tests.
For additional information, refer to Generator On- Vehicle Tests in this section.
z If the voltage increases as specified, the charging system is operating normally. NOISE
z
Disconnect: Generator C102c (4.6L 4V) or
C102a (3.8L or 4.6L 2V).
z Key in START position.
z With the engine running, turn the headlights
on, rear defroster on, and the blower motor to
the HI position.
z Is the noise still present? Yes
GO to
G4 .
No
INSTALL a new generator. REFER to
Section 414 - 02 . TEST the system for
normal operation. G4 CHECK GENERATOR FOR MECHANICAL
NOISE z
Key in OFF position.
z Connect: Generator C102c (4.6L 4V) or C102a
(3.8L or 4.6L 2V).
z Key in START position.
z Turn all accessories off. With the engine
running, use a stethoscope or equivalent
listening device to probe the generator for
unusual mechanical noise.
z Is the generator the noise source? Yes
INSTALL a new generator. REFER to
Section 414
- 02 . TEST the system for
normal operation.
No
REFER to Section 303 - 00 to diagnose
the source of engine noise. Test Step Result / Action to Take
H1 VERIFY GENERATOR IS SOURCE OF
RADIO INTERFERENCE z
Key in START position.
z With the engine running, tune the radio to
a station where the interference is present.
z Key in OFF position.
z Disconnect: Generator C102c (4.6L 4V) or
C102a (3.8L or 4.6L 2V).
z Key in START position.
z With the engine running, note any radio
interference.
z Is the interference present with the
generator disconnected? Yes
REFER to
Section 415 - 00 for diagnosis and
testing of the in- vehicle entertainment
system.
No
INSTALL a new generator. REFER to
Section 414 - 02 . TEST the system for normal
operation. Klj . 10 ba
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Battery—
Drain Tests
NOTE: No production vehicle should have more than a 50 mA (0.050 amp) continuous draw.
Check for current drains on the battery in excess of 50 milliamps (0.050 amp) with all the electrical
accessories off and the vehicle at rest. Current drains can be tested with the following procedure:
WARNING: Do not attempt this test on a lead- acid battery that has recently been
recharged. Explosive gases can cause personal injury.
CAUTION: To prevent damage to the meter, do not crank the engine or operate
accessories that draw more than 10A.
NOTE: Many modules draw 10 mA (0.010 amp) or more continuously.
NOTE: Use an in- line ammeter between the battery positive or negative post and its respective cable.
NOTE: Typically, a drain of approximately one amp can be attributed to an engine compartment lamp,
glove compartment lamp, or luggage compartment lamp staying on continually. Other component
failures or wiring shorts may be located by selectively pulling fuses to pinpoint the location of the
current drain. When the current drain is found, the meter reading will fall to an acceptable level. If the
drain is still not located after checking all the fuses, it may be due to the generator.
NOTE: To accurately test the drain on a battery, an in- line digital ammeter must be used. Use of a test
lamp or voltmeter is not an accurate method due to the number of electronic modules.
1. Make sure the junction box/fuse panels are accessible without turning on interior and underhood lights.
2. Drive the vehicle at least five minutes and over 48 km/h (30 mph) to turn on and exercise vehicle systems.
3. Allow the vehicle to sit with the key off for at least 40 minutes to allow modules to time out/power down.
4. Connect a fused jumper wire between the negative battery cable and the negative battery post to prevent modules from resetting and to catch capacitive drains.
5. Disconnect the negative battery cable from the post without breaking the connection of the jumper wire.
6. NOTE: It is very important that continuity is not broken between the battery and the negative
battery cable when connecting the meter. If this happens, the entire procedure must be
repeated.
Connect the tester between the negative battery cable and the post. The meter must be capable
of reading milliamps and should have a 10 amp capability.
7. NOTE: If the meter settings need to be switched or the test leads need to be moved to another
jack, the jumper wire must be reinstalled to avoid breaking continuity.
Remove the jumper wire.
NOTE: Amperage draw will vary from vehicle to vehicle depending on the equipment package.
Compare to a comparable vehicle for reference.
NOTE: No production vehicle should have more than a 50 mA (0.050 amp) draw. Klj . 11 ba
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Component Tests
Grid Wire Test
1. Using a bright lamp inside the vehicle, inspect the wire grid from the exterior. A broken grid wire will appear as a brown spot.
2. Run the engine at idle. Set the rear window defrost switch to ON. The indicator light should come on.
3. Working from the interior of the vehicle with a voltmeter, contact the broad red- brown stripes of
the rear glass window positive lead to battery side and negative lead to ground side. The meter
should read 10- 13 volts. A lower voltage reading indicates a loose ground connection.
4. Contact a good ground point with the negative lead of the meter. The voltage reading should not differ.
5. With the negative lead of the meter grounded, touch each grid line of the heated rear window glass at its midpoint with the positive lead. A reading of approximately 6 volts indicates that the
line is good. A reading of zero volts indicates that the line is broken between the midpoint and
the B+ side of the grid line. A reading of 12 volts indicates that the circuit is broken between the
midpoint of the grid line and ground. z
Is the voltage greater than 10 volts? I4 CHECK THE ICM FOR CORRECT OPERATION
z
Disconnect all ICM connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all ICM connectors and make sure they seat
correctly.
z Operate the system and verify the concern is still
present.
z Is the concern still present? Yes
INSTALL a new ICM. REFER
to Section 413
- 01 . CLEAR the
DTCs. REPEAT the self-test.
No
The system is operating
correctly at this time. Concern
may have been caused by a
loose or corroded connector.
CLEAR the DTCs. REPEAT
the self- test. Klj . 31 ba
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