2003 FORD MUSTANG brake

O12 DETERMINE IF THE GEM IS INTERNALLY GROUNDED
z
Key in OFF position.
z Disconnect: GEM C201e.
z Key in ON position.
z Observe the BRAKE warning indicator.
z Is BRAKE warning indicator always on? Yes
GO to
O13 .
No
GO to O14 .
O13 CHECK CIRCUIT 128 (VT/YE) FOR SHORT TO GROUND
BETWEEN GEM AND INSTRUMENT CLUSTER z
Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Measure the resistance between the GEM C201e pin 13,
circuit 128 (VT/YE), harness side and ground.
z Is resistance greater than 10,000 ohms? Yes
GO to
O15 .
No
REPAIR the circuit. TEST
the system for normal
operation. O14 CHECK FOR CORRECT GEM OPERATION
z
Disconnect all GEM connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all GEM 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 GEM.
REFER to
Section 419 - 10 .
TEST the system for normal
operation.
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. O15 CHECK FOR CORRECT INSTRUMENT CLUSTER
OPERATION z
Disconnect all instrument cluster connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster 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 instrument
cluster. REFER to
Instrument Cluster
in this
section. TEST the system
for normal operation.
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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PINPOINT TEST R: THE ABS WARNING INDICATOR IS NEVER ON z
Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Key in ON position.
z Measure the voltage between the instrument cluster C220b
pin 2, circuit 12 (LG/BK), harness side and ground, while
turning the high beams on and off.
z Is the voltage 0 volts with the high beams off and
greater than 10 volts with the high beams on? Yes
GO to
Q3 .
No
REPAIR the circuit. TEST
the system for normal
operation. Q3 CHECK FOR CORRECT INSTRUMENT CLUSTER
OPERATION z
Disconnect all instrument cluster connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster 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 instrument
cluster. REFER to
Instrument Cluster
in this
section. TEST the system
for normal operation.
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. Test Step Result / Action to Take
R1 CHECK THE ABS WARNING INDICATOR OPERATION
CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector.
z Key in ON position.
z Observe the ABS warning indicator. The ABS indicator
should prove out for approximately six seconds then turn off.
z Does the ABS warning indicator operate correctly? Yes
The system is operating
normally at this time.
No
If the indicator is
inoperative, GO to
R2 .
If the indicator is always
on, REFER to Section 206 -
09A or
Section 206 - 09B .
R2 CHECK THE INSTRUMENT CLUSTER INPUT
z
Key in OFF position.
z Disconnect: Anti- Lock Brake Control Module C135.
z Connect a fused (10A) jumper wire between the anti- lock
brake control module C135 pin 16, circuit 603 (DG), harness Yes
REFER to
Section 206 - 09A
or
Section 206 - 09B . Klj . 34 ba
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PINPOINT TEST S: THE SERVICE ENGINE SOON INDICATOR IS
NEVER/ALWAYS ON side and ground.
z Key in ON position.
z Does the ABS indicator illuminate? No
GO to
R3 .
R3 CHECK CIRCUIT 603 (DG) FOR AN OPEN
z
Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Measure the resistance between the instrument cluster
C220b pin 15, circuit 603 (DG), harness side and the anti-
lock brake control module C135 pin 16, circuit 603 (DG),
harness side.
z Is the resistance less than 5 ohms? Yes
GO to
R4 .
No
REPAIR the circuit. TEST
the system for normal
operation. R4 CHECK FOR CORRECT INSTRUMENT CLUSTER
OPERATION z
Disconnect all instrument cluster connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster 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 instrument
cluster. REFER to
Instrument Cluster
in this
section. TEST the system
for normal operation.
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. Test Step Result / Action to Take
S1 CARRY OUT THE INSTRUMENT Klj . 35 ba
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GENERAL PROCEDURES
Belt Minder Deactivating/Activating
Preparation
1. Before deactivating/activating the belt minder, set the parking brake.
2. Place the gearshift in P (Park) (automatic transmission) or the neutral position (manual transmission).
3. Place the ignition switch in the OFF position.
4. Close all the vehicle doors.
5. Unbuckle the driver safety belt.
6. Place the parklamps/headlamps switch in the OFF position. (If the vehicle is equipped with Autolamps, this will not affect the procedure.)
Deactivating/Activating 1. Turn the ignition switch to the RUN position. (Do not start the engine.)
2. Wait until the safety belt warning lamp turns off. (approximately one to two minutes)
3. NOTE: Steps 3 through 5 must be completed within 60 seconds or the procedure must be
repeated.
Buckle then unbuckle the safety belt three times, ending with the safety belt unbuckled. This
portion of the procedure can be done before or during belt minder warning activation.
4. Turn the parklamps/headlamps on then off.
5. Buckle then unbuckle the safety belt three times ending with the safety belt unbuckled. After this step the safety belt warning lamp will be illuminated for three seconds.
6. Within seven seconds of the safety belt warning lamp turning off, buckle then unbuckle the safety belt. This will enable the belt minder if disabled or disable the belt minder if enabled.
7. The following sequence of events confirm the belt minder is enabled: zflashing of the safety belt warning belt lamp four times per second for three seconds
z three seconds with the safety belt lamp off
z flashing the safety belt lamp four times per second for three seconds again
8. The safety belt lamp flashing four times per second for three seconds provides confirmation that the belt minder is disabled. 9. After confirmation, the deactivation/activation procedure is complete. SECTION 413-
09: Warning Devices 2003 Mustang Workshop Manual Klj . 1 ba
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8. If the draw is found to be excessive, pull fuses from the battery/central junction box one at a
time and note the current drop. Do not reinstall the fuses until you are finished testing.
9. Check the wiring schematic in the wiring diagram for any circuits that run from the battery without passing through the battery/central junction box. Disconnect these circuits if the draw is
still excessive.
Battery— Electronic Drains Which Shut Off When the Battery Cable is Disconnected
1. Repeat the steps of the battery drain testing.
2. Make sure all doors are closed and accessories are off. Without starting the engine, turn the ignition switch to RUN for a moment and then OFF. Wait a few minutes for the illuminated entry
lamps to turn off if equipped.
3. Connect the ammeter and read the amperage draw.
The current reading (current drain) should be less than 50 mA (0.05 amp). If the current drain exceeds
50 mA (0.05 amp) after a few minutes, and if this drain did not show in previous tests, the drain is most
likely caused by an inoperative electronic component. As in previous tests, remove the fuses from the
battery/central junction box one at a time to locate the problem circuit.
Generator On- Vehicle Tests
CAUTION: To prevent damage to the generator, do not make jumper wire connections
except as directed.
CAUTION: Do not allow any metal object to come in contact with the housing and the
internal diode cooling fins with key on or off. A short circuit will result and burn out the diodes.
NOTE: Battery posts and cable clamps must be clean and tight for accurate meter indications.
NOTE: Refer to the Battery Tester Procedure Manual for complete directions for testing the charging
system.
1. Turn off all lamps and electrical components.
2. Place the vehicle in transmission range NEUTRAL and apply the parking brake.
3. Carry out the Load Test and No- Load Test according to the following component tests:
Generator On- Vehicle Tests— Load Test
1. Switch the battery tester to the ammeter function.
2. Connect the positive and negative leads of the battery tester to the corresponding battery terminals.
3. Connect the current probe to the generator B+ output terminal, circuit 38 (BK/OG). Klj . 12 ba
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DESCRIPTION AND OPERATION
Exterior Lighting
The exterior lighting system consists of the following components:
zheadlamps (13008)
z parking lamps
z rear lamps (13404)
z high mounted stoplamp
z license lamps
z front turn lamps
z reversing lamps
z fog lamps (if equipped)
z headlamp switch (11654)
z fog lamp switch (if equipped)
z brake pedal position (BPP) switch (13480)
z multifunction switch (13K359)
z digital transmission range (DTR) sensor (A/T)
z reversing lamp switch (M/T)
z electronic flasher
z fog lamp relays (if equipped)
SECTION 417-
01: Exterior Lighting 2003 Mustang Workshop Manual Klj . 1 ba
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DIAGNOSIS AND TESTING
Stoplamps
Refer to Wiring Diagrams Cell
90 , Turn/Stop/Hazard Lamps for schematic and connector information.
Inspection and Verification 1. Verify the customer concerns.
2. Visually inspect for the following obvious signs of mechanical or electrical damage.
3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
4. If the concern is not visually evident, determine the symptom and refer to the Symptom Chart.
Symptom Chart SECTION 417-
01: Exterior Lighting 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter or
equivalent
105-
R0057
Visual Inspection Chart Mechanical Electrical
z
Brake pedal position (BPP) switch z
Central junction box (CJB) fuse 41 (15A)
z Circuitry
z Bulb(s)
Symptom Chart Condition
Possible Sources Action
z The stoplamps are
inoperative z
Central junction box (CJB)
fuse 41 (15A).
z Circuitry.
z Brake pedal position
(BPP) switch. z
Go To Pinpoint Test G .
z One or more stoplamps
are inoperative z
Circuitry.
z Multifunction switch. z
Go To Pinpoint Test H .
z The stoplamps are on
continuously z
Brake pedal position
(BPP) switch.
z Multifunction switch. z
Go To Pinpoint Test I . Klj . 1 ba
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Pinpoint Tests
PINPOINT TEST G: THE STOPLAMPS ARE INOPERATIVE
PINPOINT TEST H: ONE OR MORE STOPLAMPS ARE INOPERATIVE
Test Step Result / Action to Take
G1 CHECK CIRCUIT 10 (LG/RD) FOR AN OPEN
z
Disconnect: Brake Pedal Position (BPP) Switch C278.
z Measure the voltage between the BPP switch C278,
circuit 10 (LG/RD), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
G2 .
No
REPAIR the circuit. TEST the
system for normal operation. G2 CHECK THE CIRCUIT 810 (RD/LG) FOR AN OPEN
z
Connect a 10A fused jumper wire between C278, circuit
10 (LG/RD), harness side and C278, circuit 810 (RD/LG),
harness side.
z Do the stoplamps illuminate? Yes
INSTALL a new BPP switch.
REFER to
Lamp Switch —
Brake Pedal Position (BPP) in
this section. TEST the system
for normal operation.
No
REPAIR circuit 810 (RD/LG)
or 569 (DG) as necessary.
TEST the system for normal
operation. Test Step Result / Action to
Take H1 CHECK THE VOLTAGE TO THE INOPERATIVE STOPLAMP
z
Disconnect: Inoperative Stoplamp.
z If a rear stoplamp is inoperative, measure the voltage between
the inoperative stoplamp connector circuit 9 (LG/OG) (LH) or
circuit 5 (OG/LB) (RH), harness side and ground, while pressing
the brake pedal. Yes
REPAIR circuit 1205
(BK). TEST the system
for normal operation.
No
If high mounted
stoplamp, REPAIR
circuit 569 (DG). TEST
the system for normal Klj . 2 ba
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