wiring FORD MUSTANG 2003 Workshop Manual

z
Is the noise eliminated? B4 CHECK GENERATOR
z
Key in OFF position.
z Check the generator by disconnecting
the wiring from the voltage regulator.
z Key in START position.
z Turn on the audio unit and check the
radio reception.
z Is the noise eliminated? Yes
INSTALL a new generator. REFER to
Section 414 - 02 . TEST the system for normal operation.
No
GO to B5 .
B5 CHECK IGNITION CIRCUITS
z
Key in OFF position.
z Check the ignition circuits for correct
routing, grounding, and integrity of
connections.
z Are the ignition components OK? Yes
GO to
B6 .
No
REPAIR the ignition system as necessary. TEST
the system for normal operation. B6 SUBSTITUTE ANTENNA
z
Substitute a known good antenna.
Ground the antenna base to an
unpainted metal surface on the vehicle.
z Key in START position.
z Verify the operation of the audio unit.
z Is the noise eliminated? Yes
INSTALL a new antenna. TEST the system for
normal operation.
No
GO to
B7 .
B7 SUBSTITUTE ANTENNA CABLE
z
Key in OFF position.
z Substitute a known good antenna
cable.
z Key in START position.
z Verify the operation of the audio unit.
z Is the noise eliminated? Yes
INSTALL a new antenna cable. TEST the system
for normal operation.
No
GO to
B8 .
B8 SUBSTITUTE AUDIO UNIT
z
Key in OFF position.
z Substitute a known good audio unit.
z Key in START position.
z Verify the operation of the audio unit.
z Is the noise eliminated? Yes
REMOVE the audio unit and SEND it to an
authorized Ford audio system repair facility.
TEST the system for normal operation.
No
GO to
B9 .
B9 SUBSTITUTE SUBWOOFER
AMPLIFIER z
Key in OFF position.
z Substitute a known good subwoofer
amplifier.
z Key in START position.
z Verify the operation of the audio unit.
z Is the noise eliminated? Yes
REMOVE the subwoofer amplifier and SEND it to
an authorized Ford audio system repair facility.
TEST the system for normal operation.
No
GO to
B10 .
B10 REPOSITION COMPONENTS
z
Key in OFF position.
z Determine if the noise can be
eliminated by repositioning the antenna
cable, speaker circuits, or audio unit
power feed circuits away from other
circuits or brackets.
z Key in START position.
z Verify the operation of the audio unit. Yes
Permanently REPOSITION the components as
needed. TEST the system for normal operation.
No
GROUND various parts (for example, engine,
fenders, quarter panels, stone deflectors, body
sheet metal) of the vehicle to the frame using a Klj . 6 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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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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DIAGNOSIS AND TESTING
Turn Signal and Hazard Lamps
Refer to Wiring Diagrams Cell
90 , Turn/Stop/Hazard Lamps for schematic and connector information.
Inspection and Verification 1. Verify the customer concern.
2. Visually inspect for the following obvious signs of mechanical and 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 cause is not visually evident, verify the symptom and refer to the Symptom Chart.
Symptom Chart SECTION 417-
01: Exterior Lighting 2003 Mustang Workshop Manual Special Tool(s)
73 III Automotive Meter
105-
R0057 or equivalent
Visual Inspection Chart Mechanical Electrical
z
Multifunction switch z
Central junction box (CJB) Fuse 13 (15A).
z CJB Fuse 18 (15A).
z Circuitry
z Electronic flasher
z Turn signal/hazard lamp
Symptom Chart Condition
Possible Sources Action
z The turn signal
lamps are never
on z
Central junction
box (CJB) fuse 13
(15A).
z CJB Fuse 18
(15A).
z Circuitry.
z Multifunction
switch. z
Go To Pinpoint Test J . Klj . 1 ba
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PINPOINT TEST K: THE HAZARD FLASHER LAMPS ARE NEVER ON z
Disconnect: Multifunction Switch C202b.
z Measure the resistance between multifunction switch C202b Pin
44, Circuit 44 (LB), harness side and the electronic flasher C2141
Pin 1, Circuit 44 (LB), harness side; and between multifunction
switch C202b Pin 44, Circuit 44 (LB), harness side and ground.
z Is the resistance less than 5 ohms between the multifunction
switch and the electronic flasher, and greater than 10,000
ohms between the multifunction switch and ground? GO to
J3 .
No
REPAIR the circuit.
TEST the system for
normal operation. J3 CHECK THE CONTINUITY OF THE MULTIFUNCTION SWITCH
z
Carry out the multifunction switch component test.
Refer to Wiring Diagrams Cell 149 for schematic and connector
information.
z Is the switch OK? Yes
INSTALL a new
electronic flasher.
TEST the system for
normal operation.
No
INSTALL a new
multifunction switch.
REFER to
Section 211 - 05 . TEST the
system for normal
operation. Test Step Result / Action to
Take K1 CHECK THE VOLTAGE TO THE ELECTRONIC FLASHER
z
Disconnect: Electronic Flasher C2141.
z Measure the voltage between electronic flasher C2141 Pin 3,
Circuit 383 (RD/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
K2 .
No
REPAIR the circuit.
TEST the system for
normal operation. K2 CHECK CIRCUIT 385 (WH/RD)
z
Disconnect: Multifunction Switch C202b. Yes Klj . 3 ba
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z
Measure the resistance between multifunction switch C202b Pin
385, Circuit 385 (WH/RD), harness side and electronic flasher
C2141 Pin 4, Circuit 385 (WH/RD), harness side; and between
multifunction switch C202b Pin 385, Circuit 385 (WH/RD), harness
side and ground.
z Is the resistance less than 5 ohms between the multifunction
switch and the electronic flasher, and greater than 10,000
ohms between the multifunction switch and ground? GO to
K3 .
No
REPAIR the circuit.
TEST the system for
normal operation. K3 CHECK THE CONTINUITY OF THE MULTIFUNCTION SWITCH
z
Carry out the multifunction switch component test.
Refer to Wiring Diagrams Cell 149 for schematic and connector
information.
z Is the switch OK? Yes
INSTALL a new
electronic flasher.
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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DIAGNOSIS AND TESTING
Parking, Rear and License Lamps
Refer to Wiring Diagrams Cell
92 , Exterior for schematic and connector information.
Inspection and Verification 1. Verify the customer concern by operating the parking lamps.
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)
73 III Automotive Meter or
equivalent
105-
R0057
Visual Inspection Chart Mechanical Electrical
z
Damaged multifunction switch
(13K359)
z Damaged headlamp switch (11654) z
Blown battery junction box (BJB) Fuse 2
(30A)
z Damaged wiring harness
z Loose or corroded connections
z Damaged parking, rear or license lamp
Symptom Chart Condition
Possible Sources Action
z The parking, rear or license
lamps are inoperative z
BJB Fuse 2 (30A).
z Circuitry.
z Headlamp switch. z
GO to Pinpoint Test L .
z One or more parking, rear or
license bulbs(s) is inoperative z
Parking, rear or
license bulb(s).
z Circuitry. z
GO to Pinpoint Test M .
z The parking, rear or license
lamps are on continuously z
Headlamp switch.
z Circuitry. z
GO to Pinpoint Test N . Klj . 1 ba
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DIAGNOSIS AND TESTING
Fog Lamps
Refer to Wiring Diagrams Cell
86 , Fog Lamps for schematic and connector information.
Principles of Operation
The fog lamps will only illuminate when the low beam or parking lamps are illuminated. Voltage from
the parking lamp circuit is used to activate the fog lamp relay when the fog lamp switch is ON. Voltage
from the high beam headlamp circuit will activate the fog lamp interrupt relay. When the fog lamp
interrupt relay is active, the ground path is removed from the fog lamp relay, turning off the fog lamps.
Inspection and Verification 1. Verify the customer concern by operating the fog lamps.
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)
73 III Automotive Meter or
equivalent
105-
R0057
Visual Inspection Chart Mechanical Electrical
z
Damaged headlamp switch (11654)
z Damaged fog lamp switch
z Damaged multifunction switch
(13K359) z
Blown battery junction box (BJB) Fuse 27
(20A)
z Blown central junction box (CJB) Fuse 38
(20A)
z Damaged wiring harness
z Loose or corroded connections
z Damaged fog lamp relay
z Damaged fog lamp interrupt relay
z Damaged fog lamp
Symptom Chart Klj . 1 ba
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Pinpoint Tests
PINPOINT TEST O: THE FOG LAMPS ARE INOPERATIVE Condition
Possible Sources Action
z The fog lamps are
inoperative z
BJB Fuse 27 (20A).
z CJB Fuse 38 (20A).
z Circuitry.
z Fog lamp relay.
z Fog lamp interrupt
relay.
z Headlamp switch.
z Fog lamp switch.
z Multifunction switch. z
GO to Pinpoint Test O .
z The individual fog lamp is
inoperative z
Fog lamp bulb.
z Circuitry. z
GO to Pinpoint Test P .
z The fog lamps are on
continuously z
Fog lamp relay.
z Circuitry.
z Fog lamp switch. z
GO to Pinpoint Test Q .
Test Step Result / Action
to Take O1 CHECK THE PARK LAMPS
z
Place the headlamp switch in the PARK position.
z Place the multifunction switch in low beam position.
z Do the park lamps illuminate? Yes
Turn off the
headlamp switch.
GO to
O2 .
No
GO to Pinpoint Test L .
O2 CHECK THE FOG LAMP RELAYS
z
Disconnect: Fog Lamp Relay.
z Disconnect: Fog Lamp Interrupt Relay.
z Check the fog lamp relay and fog lamp interrupt relay; refer to Wiring
Diagrams Cell 149.
z Are the relays OK? Yes
GO to
O3 .
No
INSTALL new
relay(s). TEST
the system for
normal
operation. O3 CHECK THE CIRCUIT 12 (LG/BK)
z
Measure the voltage between fog lamp interrupt relay connector Pin 1,
Circuit 12 (LG/BK), harness side and ground. Yes
GO to
O4 .
No
REPAIR the
circuit. TEST the
system for
normal
operation. Klj . 2 ba
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PINPOINT TEST Q: THE FOG LAMPS ARE ON CONTINUOUSLY z
Is the resistance less than 5 ohms? No
REPAIR Circuit 1205
(BK). TEST the system
for normal operation.
Test Step Result / Action to Take
Q1 CHECK THE FOG LAMP RELAY
z
Disconnect: Fog Lamp Relay.
z Are the fog lamps off? Yes
GO to
Q2 .
No
REPAIR Circuit 478 (TN/OG). TEST the system
for normal operation. Q2 CHECK FOG LAMP RELAY
z
Check the fog lamp relay; refer to
Wiring Diagrams Cell 149.
z Is the fog lamp relay OK? Yes
RECONNECT the fog lamp relay. GO to
Q3 .
No
INSTALL a new fog lamp relay. TEST the system
for normal operation. Q3 CHECK FOG LAMP SWITCH
z
Disconnect: Fog Lamp Switch C240.
z Are the fog lamps off? Yes
INSTALL a new fog lamp switch. TEST the
system for normal operation.
No
REPAIR Circuit 188 (WH/BK) for short. TEST the
system for normal operation. Klj . 5 ba
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