2003 FORD MUSTANG fuse box

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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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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DIAGNOSIS AND TESTING
Audio System
Refer to Wiring Diagrams Cell
130 , Radio for schematic and connector information.
Inspection and Verification 1. Verify the customer concern by operating the electronic audio system with the engine running.
2. Visually inspect the following for obvious signs of mechanical and electrical damage.
3. If the concern remains and the fault is not detected, proceed to the Symptom Chart to continue diagnostics.
Symptom Chart SECTION 415-
00: Entertainment System — General Information 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter
105-
R0057 or equivalent
Visual Inspection Chart Mechanical Electrical
z
Audio unit
z Antenna or antenna cable
z Speakers mounting/speaker cones
z Radio ignition interference capacitor, radio frequency
interference suppression bond or radio receiver hood bonding
strap cleanliness z
Battery junction box
(BJB) fuses:
„3 (40A)
„ 4 (40A)
„ 6 (40A)
z Central junction box
(CJB) fuses:
„6 (20A)
„ 27 (25A)
„ 32 (15A)
z Ignition switch
z Circuitry
z Audio unit
Symptom Chart Condition
Possible Sources Action
z The audio unit is
inoperative/does not operate z
Central
junction box z
Go To Pinpoint Test A . Klj . 1 ba
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correctly
(CJB) fuses:
„6
(20A).
„ 27
(25A).
„ 32
(15A).
z Battery
junction box
(BJB) fuses:
„3
(40A).
„ 4
(40A).
„ 6
(40A).
z Circuitry.
z Audio unit.
z Ignition
switch.
z Audio unit display blank —
audio unit operates z
Audio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation.
z Tape player only inoperative zAudio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation.
z Poor reception zAntenna
connections.
z Antenna
cable.
z Noise
suppression
equipment.
z Audio unit.
z Generator.
z Ignition
system. z
Go To Pinpoint Test B .
z Poor reception — FM only zFM signal out
of range. z
INFORM customer
of methods for
obtaining best
reception.
z Continuous SEEK/SCAN in
AM/FM z
Antenna.
z Antenna
connections.
z Audio unit. z
Go To Pinpoint Test C .
z No sound from one or more of
the speakers — not all speakers z
Speaker(s).
z Circuitry.
z Audio unit.
z Subwoofer
amplifier. z
Go To Pinpoint Test D .
z No sound from all of the zAudio unit. zGo To Pinpoint Test Klj . 2 ba
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DIAGNOSIS AND TESTING
Headlamps
Refer to Wiring Diagrams Cell
85 , Headlamps for schematic and connector information.
Inspection and Verification 1. Verify the customer concern by operating the headlamps.
2. Visually inspect for the following obvious signs of mechanical and electrical damage.
3. If the concern is not visually evident, determine the symptom and proceed to 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
Damaged headlamp switch (11654)
z Damaged multifunction switch (13K359) z
Battery junction box (BJB) fuse 2 (30A)
z Central junction box (CJB) fuse(s):
„38 (20A)
„ 4 (7.5A) (RH)
„ 10 (7.5A) (LH)
z Damaged wiring harness
z Loose or corroded connections
z Headlamp bulb
Symptom Chart Condition
Possible Sources Action
z Both
headlamps are
inoperative z
Battery junction
box (BJB) fuse 2
(30A).
z Headlamp
switch.
z Circuitry.
z Multifunction
switch. z
Go To Pinpoint Test A .
z The low beams
are inoperative z
Circuitry.
z Multifunction
switch. z
Go To Pinpoint Test B . Klj . 1 ba
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Pinpoint Tests
PINPOINT TEST A: BOTH HEADLAMPS ARE INOPERATIVE z
The high beams
are inoperative z
Central junction
box (CJB) fuse
38 (20A).
z Circuitry.
z Multifunction
switch. z
Go To Pinpoint Test C .
z One low beam
headlamp is
inoperative z
Central junction
box (CJB) fuse
(s):
„10 (7.5A)
(LH).
„ 4 (7.5A)
(RH).
z Headlamp bulb.
z Circuitry. z
Go To Pinpoint Test D .
z One high beam
headlamp is
inoperative z
Headlamp bulb.
z Circuitry. z
Go To Pinpoint Test E .
z The headlamps
are on
continuously z
Headlamp
switch.
z Circuitry.
z Multifunction
switch. z
Go To Pinpoint Test F .
z The flash- to-
pass feature is
inoperative z
Circuitry.
z Multifunction
switch. z
CHECK Circuit 196 (DB/OG) for
an open. REPAIR if necessary. IF
OK, INSTALL a new multifunction
switch; REFER to Section 211 -
05 . TEST the system for normal
operation. Test Step Result / Action to Take
A1 CHECK THE VOLTAGE TO THE HEADLAMP SWITCH
z
Disconnect: Headlamp Switch C205.
z Measure the voltage between headlamp switch C205 Pin
B1, Circuit 196 (DB/OG), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
A2 .
No
REPAIR the circuit. TEST
the system for normal
operation. A2 CHECK CIRCUIT 15 (RD/YE) FOR OPEN
z
Disconnect: Multifunction Switch C202a. Yes Klj . 2 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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operation.
I2 CHECK THE SPEED
CONTROL SYSTEM z
Disconnect: Speed Control
Servo C122.
z Do the stoplamps continue
to illuminate? Yes
GO to
I3 .
No
REFER to Section 310 - 03 .
I3 CHECK CIRCUIT 511 (LG)
FOR SHORT TO POWER z
Disconnect: Central Junction
Box (CJB) Fuse 35 (15A).
z Do the stoplamps continue
to illuminate? Yes
GO to
I4 .
No
REPAIR the circuit. TEST the system for normal operation. I4 CHECK CIRCUIT 810 (LG/RD)
FOR SHORT TO POWER z
Disconnect: CJB Fuse 41
(15A).
z Do the stoplamps continue
to illuminate? Yes
GO to
I5 .
No
REPAIR the circuit. TEST the system for normal operation. I5 CHECK THE
MULTIFUNCTION SWITCH z
Disconnect: Multifunction
Switch C202b.
z Do the stoplamps continue
to illuminate? Yes
If the high mounted stoplamp is illuminated, REPAIR circuit
569 (DG) or 511 (LG) as necessary. TEST the system for
normal operation.
If only the LH stoplamp is illuminated, REPAIR circuit 9
(LG/OG). TEST the system for normal operation.
If only the RH stoplamp is illuminated, REPAIR circuit 5
(OG/LB). TEST the system for normal operation.
No
INSTALL a new multifunction switch. REFER to
Section 211 - 05 . TEST the system for normal operation. Klj . 4 ba
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