FORD MUSTANG 2003 Workshop Manual

z
Is the voltage greater than zero volts? F4 CHECK CIRCUIT 13 (RD/BK) FOR SHORT TO POWER
z
Remove Fuse 4 (7.5A) and Fuse 10 (7.5A) from the
CJB.
z Measure the voltage between multifunction switch
C202a Pin 507, Circuit 13 (RD/BK), harness side and
ground.
z Is the voltage greater than 0 volts? Yes
REPAIR the circuit. TEST the
system for normal operation.
No
GO to
F5 .
F5 CHECK CIRCUIT 1056 (DB, LG) FOR VOLTAGE
z
Disconnect: Headlamp C1041.
z Measure the voltage between RH headlamp C1041 Pin
3, Circuit 1056 (DB/LG), harness side and ground.
z Is the voltage greater than 0 volts? Yes
REPAIR Circuit 1056 (DB/LG).
TEST the system for normal
operations.
No
REPAIR Circuit 1055 (WH/LG).
TEST the system for normal
operations. Klj . 7 ba
82003 Mustang Workshop Manual
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Klj . 8 ba
82003 Mustang Workshop Manual
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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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PINPOINT TEST I: THE STOPLAMPS ARE ON CONTINUOUSLY z
If the high mounted stoplamp is inoperative, measure the voltage
between the inoperative high mounted stoplamp C475 (C4199 for
Cobra) pin 1, circuit 569 (DG), harness side and ground while
pressing the brake pedal.
z Is the voltage greater than 10 volts? operation.
If rear stoplamp, GO to
H2
.
H2 CHECK CIRCUIT 9 (LG/OG) OR 5 (OG/LB) FOR AN OPEN
z
Disconnect: Multifunction Switch C202b.
z Measure the resistance between the inoperative stoplamp
connector and multifunction switch C202b pin 9, circuit 9
(LG/OG) (LH), or C202b pin 5, circuit 5 (OG/LB) (RH).
z Is the resistance less than 5 ohms? Yes
INSTALL a new
multifunction switch.
REFER to
Section 211 - 05 . TEST the
system for normal
operation.
No
REPAIR the circuit in
question. TEST the
system for normal
operation. Test Step Result / Action to Take
I1 CHECK THE BRAKE PEDAL
POSITION (BPP) SWITCH z
Key in OFF position.
z Disconnect: BPP Switch
C278.
z Do the stoplamps continue
to illuminate? Yes
GO to
I2 .
No
INSTALL a new BPP switch. REFER to Lamp Switch —
Brake Pedal Position (BPP) . TEST the system for normal Klj . 3 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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Klj . 5 ba
52003 Mustang Workshop Manual
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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 Tests
PINPOINT TEST J: THE TURN SIGNAL LAMPS ARE NEVER ON z
Electronic flasher.
z The hazard
flasher lamps are
never on z
Central junction
box (CJB) fuse 13
(15A).
z Circuitry.
z Multifunction
switch.
z Electronic flasher. z
Go To Pinpoint Test K .
z One turn
signal/hazard
lamp is never on z
Turn
signal/hazard
flasher lamp.
z Circuitry. z
REPAIR inoperative turn
signal/hazard flasher lamp
circuit
„LF Circuit 3 (LG/WH).
„ RF Circuit 2 (WH/LB).
„ LR Circuit 9 (LG/OG).
„ RR Circuit 5 (OG/LB).
z The turn signal
lamps are always
on z
Multifunction
switch. z
INSTALL a new multifunction
switch; REFER to Section 211 -
05 . TEST the system for
normal operation.
z The hazard
flasher lamps are
always on z
Multifunction
switch. z
INSTALL a new multifunction
switch; REFER to Section 211 -
05 . TEST the system for
normal operation. Test Step Result / Action to
Take J1 CHECK THE VOLTAGE TO THE ELECTRONIC FLASHER
z
Disconnect: Electronic Flasher C2141.
z Key in ON position.
z Measure the voltage between the following electronic flasher
C2141 circuits, harness side and ground.
„Pin 2, Circuit 1039 (BK/YE).
„ Pin 3, Circuit 383 (RD/WH).
z Are the voltages greater than 10 volts? Yes
GO to
J2 .
No
REPAIR the circuit in
question. TEST the
system for normal
operation. J2 CHECK CIRCUIT 44 (LB)
z
Key in OFF position. Yes Klj . 2 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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