light FORD MUSTANG 2003 Workshop Manual

DESCRIPTION AND OPERATION
Instrument Cluster and Panel Illumination
The instrument cluster and panel illumination system illuminates the following components:
zinstrument cluster (10849)
z audio unit (18806)
z A/C- heater control
z fog lamp switch
z transmission range indicator
z traction control switch
z rear window defrost control switch
The instrument cluster is a hybrid electronic cluster (HEC), which uses both hardwired circuitry and the
standard corporate protocol (SCP) communication network to transmit and receive information. The
Mustang instrument cluster backlighting has illumination bulbs that are installed separately from the
instrument cluster. The Cobra instrument cluster has a laminated, electroluminescent applique to
backlight the cluster . The electroluminescent applique and instrument cluster must be installed as an
assembly. SECTION 413-
00: Instrument Cluster and Panel Illumination 2003 Mustang Workshop Manual Klj . 1 ba
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To exit the instrument cluster self-
diagnostic mode, turn the ignition switch to the OFF position or press
and hold the SELECT/RESET button for three or more seconds and release. z
93- 102 = 6.9- 9.1 volts (low voltage)
z 115- 124 = 8.5- 10.7 volts (norm band start)
z 215- 225 = 15.8- 18 volts (norm band end)
z 230- 241 = 16.9- 19.1 volts (high voltage) rhEo Displays the present decimal rheostat dimming input, 0-
255 (used when requesting
assistance from the hotline). rhi
rhS rho Not used.
Cr Displays the present RUN/START sense input. Display will show -
h for high input with
the ignition switch in the START position and - L for low input with the ignition switch in
the RUN position. PA-
PE7 Not used.
GAGE Repeats test display cycle.
Instrument Cluster Diagnostic Trouble Code (DTC) Index Diagnostic
Tool
Displayed DTC Self-
Diagnostic
Mode Displayed DTC Description Source Action
B1202 9202 Fuel Sender
Open Circuit Instrument
Cluster Go To Pinpoint Test B .
B1204 9204 Fuel Sender
Short to Ground Instrument
Cluster Go To Pinpoint Test B .
B1317 9317 Battery Voltage
High Instrument
Cluster Section 414 - 00 .
B1318 9318 Battery Voltage
Low Instrument
Cluster Section 414 - 00 .
B1342 9342 ECU is Defective Instrument
Cluster INSTALL a new instrument
cluster; REFER to Instrument Cluster in this section. TEST the
system for normal operation. B1343 9343 Heated Backlight
Input Circuit Failure Instrument
Cluster Section 501 - 11 .
B1356 9356 Ignition Run
Circuit Open Instrument
Cluster Go To Pinpoint Test A .
B1364 9364 Ignition Start
Circuit Open Instrument
Cluster Go To Pinpoint Test A .
B2143 A143 Odometer NVM
Mmory Failure Instrument
Cluster Go To Pinpoint Test J .
C1284 5284 Oil Pressure
Switch Failure Instrument
Cluster Go To Pinpoint Test C .
P1197 1197 Mileage Switch
Circuit Failure Instrument
Cluster Go To Pinpoint Test J . Klj . 7 ba
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DIAGNOSIS AND TESTING
Horn
Refer to Wiring Diagrams Cell
44 , Horns/Cigar Lighter for schematic and connector information.
Inspection and Verification 1. Verify the customer concern by operating the horn (13832).
2. Visually inspect for obvious signs of mechanical and electrical damage.
3. If fault is not visually evident, determine the symptom and proceed to Symptom Chart.
Symptom Chart SECTION 413-
06: Horn 2003 Mustang Workshop Manual Special Tool(s)
73 Digital Multimeter or
equivalent
105-
R0051
Visual Inspection Chart Mechanical Electrical
z
Damaged horns
z Damaged horn switch
z Damaged air bag sliding contact
(14A664) z
Blown battery junction box (BJB) Fuse Horn
Relay (20A)
z Damaged wiring harness
z Damaged connections
z Damaged horn relay
z Damaged horn switch
Symptom Chart Condition
Possible Sources Action
z The horn does not
sound z
BJB Fuse Horn Relay (20A).
z Circuitry.
z Horn relay.
z Air bag sliding contact.
z Horn switch.
z Horns. z
GO to
Pinpoint Test A .
z The horn sounds
continuously z
Circuitry.
z Horn relay.
z Remote entry system (generic
electronic module [GEM]) z
GO to
Pinpoint Test B . Klj . 1 ba
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and when the GEM detects the headlamps or parklamps are on from the exterior lamp circuits. Refer
to the Chime Duration Table in this section for audible output, duration time, and priority ratings.
Safety Belt Warning Chime
The safety belt warning chime and safety belt warning lamp activate when the GEM detects the
ignition switch circuits are in the RUN or START state and when the GEM detects the safety belt is
unbuckled from the safety belt circuit. The safety belt warning lamp indicator will prove out for three
seconds whenever the GEM detects that the ignition circuits make a transition to RUN from OFF, ACC,
or KEYOUT state. Refer to the Chime Duration Table in this section for audible output, duration time,
and priority ratings.
Belt Minder
NOTE:
Belt minder is a configurable item. If configuring using a diagnostic tool, refer to Section 418 -
01 . To configure without using a diagnostic tool, refer to
Belt Minder Deactivating/Activating in this
section.
The belt minder feature supplements the current safety belt warning function. The belt minder feature
is enabled after the current safety belt warning is complete. If the driver safety belt is not buckled
approximately five seconds after the safety belt warning light has turned off, the belt minder reminds
the driver that their safety belt is unbuckled by intermittently sound a chime and illuminating the safety
belt warning lamp in the instrument cluster. While activated, the belt minder alternates the chime and
indicator from on for six seconds to off for 30 seconds.
The belt minder reminder stops when:
zthe drive seat belt is buckled.
z the ignition is turned to OFF or ACC.
z five minutes have elapsed since belt minder has started.
Inspection and Verification
NOTE: Upon installation of a new GEM, the module must be reconfigured. For additional information,
refer to Section 418 - 01 .
1. The warning lamps are a GEM controlled system; refer to Section 419 - 10 .
2. Verify the customer concern by operating the system in question.
3. Visually inspect for the following obvious signs of mechanical and electrical damage.
Chime Duration Table Feature Audible Output Duration Priority
Safety belt Chime, 60/minute 740 Hz 6.0 seconds 1
Key-
in-ignition Chime, 120/minute 740 Hz Continuous 2
Headlamps left on Chime, 240/minute 740 Hz Continuous 3
Airbag Single tone, 1,000 Hz Continuous 4
Door ajar Single tone, 1,000 Hz 1.0 second 7 Klj . 2 ba
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PINPOINT TEST E: THE HEADLAMP ON REMINDER CHIME DOES
NOT OPERATE CORRECTLY z
Is the resistance less than 5 ohms? D16 CHECK CIRCUIT 1205 (BK) FOR OPEN BETWEEN
PASSENGER DOOR AJAR SWITCH AND GROUND z
Measure the resistance between passenger door ajar switch
C602 pin 1, circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new passenger
door ajar switch. REFER to
Section 501
- 14A . REPEAT
the self- test. CLEAR the
DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. D17 CHECK FOR CORRECT MODULE OPERATION
z
Check:
zfor corrosion
z for pushed- out pins
z connector seated correctly
z Connect any disconnected connectors.
z Make sure all other system connectors are fully seated.
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 .
CLEAR the DTCs.
REPEAT the GEM 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. Test Step Result / Action to Take
E1 CHECK FOR CORRECT OPERATION OF THE HEADLAMP
SWITCH z
Cycle the headlamp switch through all positions to verify
correct operation of exterior lighting circuits.
z Do all exterior lamps operate correctly? Yes
GO to
E2 .
No
REFER to Section 417 - 01 . Klj . 15 ba
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Functionality
With the ignition switch in the RUN position, voltage is applied through the warning indicator I circuit
904 (LG/RD) to the voltage regulator. This turns the regulator on, allowing current to flow from battery
sense A circuit 36 (YE/WH) to the generator field coil. When the engine is started, the generator
begins to generate alternating current (AC) which is internally converted to direct current (DC). This
current is then supplied to the vehicle's electrical system through the output (B+) terminal of the
generator.
Once the generator begins generating current, a voltage signal is taken from the generator stator and
fed back to the regulator internally. This voltage feedback signal (typically half the battery voltage) is
used to turn off the warning indicator.
With the system functioning normally, the generator output current is determined by the voltage of the
A circuit. The A circuit voltage is compared to a set voltage internal to the regulator, and the regulator
controls the generator field current to maintain the correct generator output.
The set voltage will vary with temperature and is typically higher in cold temperatures and lower in
warm temperatures. This allows for better battery recharge in the winter and reduces the chance of
overcharging in the summer.
Battery Positive Output Circuit 38 (B+) (BK/OG)
The generator output is supplied through the battery positive output (B+) terminal on the back of the
generator to the battery and electrical system.
I Circuit 904 (LG/RD)
The I (ignition) circuit is used to turn on the voltage regulator. This circuit is powered up with the
ignition key in the run position. This circuit is also used to turn the charging system warning indicator
on if there is a fault in the charging system operation.
A Circuit 36 (YE/WH)
The A circuit or battery sense circuit is used to sense battery voltage. This voltage is used by the
regulator to determine generator output. This circuit is used to supply current to the generator field
(rotor). The amount of current supplied to the rotor will determine generator output.
Inspection and Verification
WARNING: Batteries contain sulfuric acid. Avoid contact with skin, eyes, or clothing.
Also, shield your eyes when working near batteries to protect against possible splashing of the
acid solution. In case of acid contact with skin or eyes, flush immediately with water for a
minimum of 15 minutes and get prompt medical attention. If acid is swallowed, call a physician
immediately.
WARNING: Batteries normally produce explosive gases which can cause personal injury.
Therefore, do not allow flames, sparks or lighted substances to come near the battery. When
charging or working near a battery, always shield your face and protect your eyes. Always Connector C102a End View
A Circuit 36 (YE/WH)
I Circuit 904 (LG/RD) Klj . 2 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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DESCRIPTION AND OPERATION
Battery and Cables
Vehicles are equipped with a 12 volt maintenance-
free battery that contains a built-in hydrometer. The
hydrometer eye indication is as follows:
zA green dot means the battery is OK.
z A yellow dot, red dot, or when the green dot is not visible, means the battery needs to be
charged.
WARNING: Batteries normally produce explosive gases which can cause personal injury.
Therefore, do not allow flames, sparks or lighted substances to come near the battery. When
charging or working near a battery, always shield your face and protect your eyes. Always
provide ventilation.
WARNING: When lifting a battery, excessive pressure on the end walls could cause acid
to leak out through the vent caps, resulting in personal injury, damage to the vehicle or the
battery.
WARNING: Keep out of the reach of children. Batteries contain sulfuric acid. Avoid
contact with skin, eyes, or clothing. Also, shield your eyes when working near the battery to
protect against possible splashing of the acid solution. In case of acid contact with skin or
eyes, flush immediately with water for a minimum of 15 minutes and get prompt medical
attention. If acid is swallowed, call a physician immediately.
Ford Motor Company strongly recommends that lead- acid batteries be returned to an authorized
recycling facility for disposal. SECTION 414-
01: Battery, Mounting and Cables 2003 Mustang Workshop Manual Klj . 1 ba
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