2003 FORD MUSTANG pinpoint

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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PINPOINT TEST B: THE LOW BEAMS ARE INOPERATIVE z
Measure the resistance between headlamp switch C205 Pin
H, Circuit 15 (RD/YE), harness side and multifunction switch
C202a Pin 15, Circuit 15 (RD/YE), harness side.
z Is the resistance less than 5 ohms? RECONNECT headlamp
switch C205. GO to
A3 .
No
REPAIR the circuit. TEST
the system for normal
operation. A3 CHECK THE VOLTAGE TO THE MULTIFUNCTION SWITCH
z
Place the headlamp switch in the ON position.
z Measure the voltage between multifunction switch C202a
Pin 15, Circuit 15 (RD/YE), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new
multifunction switch;
REFER to
Section 211 - 05 .
TEST the system for
normal operation.
No
INSTALL a new headlamp
switch; REFER to Lamp Switch — Headlamp in this
section. TEST the system
for normal operation. Test Step Result / Action to Take
B1 CHECK THE VOLTAGE TO CJB FUSE 4 (7.5A) AND CJB
FUSE 10 (7.5A) z
Key in OFF position.
z Place the multifunction switch in the low beam position.
z Remove Fuse 4 (7.5A) and Fuse 10 (7.5A) from the CJB.
z Place the headlamp switch in the ON position.
z Measure the voltage between the following CJB fuse
terminals and ground:
„Fuse 4 connector.
„ Fuse 10 connector. Yes
Go To Pinpoint Test D
.
No
GO to B2 . Klj . 3 ba
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PINPOINT TEST C: THE HIGH BEAMS ARE INOPERATIVE z
Are the voltages greater than 10 volts? B2 CHECK CIRCUIT 13 (RD/BK) FOR OPEN
z
Disconnect: Multifunction Switch C202a.
z Measure the resistance between multifunction switch C202a
Pin 13, Circuit 13 (RD/BK), harness side and CJB Fuse 4
and Fuse 10.
z Are the resistances 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. TEST
the system for normal
operation. Test Step Result / Action to Take
C1 CHECK THE CIRCUIT 12 (LG/BK)
z
Disconnect: LH Headlamp C1021.
z Measure the resistance between LH headlamp C1021 Pin
2, Circuit 12 (LG/BK), harness side and CJB Fuse 38 (20A).
z Is the resistance less than 5 ohms? Yes
RECONNECT the LH
headlamp (13008). GO to
C2
.
No
REPAIR the circuit. TEST
the system for normal
operation. C2 CHECK THE VOLTAGE TO CJB FUSE 38 (20A)
z
Place the headlamp switch in the ON position.
z Place the multifunction switch in the high beam position.
z Measure the voltage between CJB Fuse 38 (20A) and
ground. Yes
Go To Pinpoint Test E
.
No Klj . 4 ba
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PINPOINT TEST D: ONE LOW BEAM HEADLAMP IS INOPERATIVE z
Is the voltage greater than 10 volts? GO to
C3 .
C3 CHECK CIRCUIT 632 (GY/OG) FOR OPEN
z
Disconnect: Multifunction Switch C202a.
z Measure the resistance between the CJB Fuse 38 (20A),
and multifunction switch C202a Pin 12, Circuit 632
(GY/OG), harness side.
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. TEST
the system for normal
operation. Test Step Result / Action to Take
D1 CHECK THE VOLTAGE TO THE INOPERATIVE HEADLAMP
BULB z
Disconnect: Inoperative Headlamp.
z Place the headlamp switch in the ON position.
z Place the multifunction switch in the low beam position.
z Measure the voltage between RH headlamp C1041 Pin 3,
Circuit 1056 (DB/LG), or LH headlamp C1021 Pin 3, Circuit
1055 (WH/LG), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new
headlamp bulb; REFER
to
Bulb — Headlamp in
this section. TEST the
system for normal
operation.
No
REPAIR the circuit. TEST
the system for normal
operation. Klj . 5 ba
82003 Mustang Workshop Manual
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PINPOINT TEST E: ONE HIGH BEAM HEADLAMP IS INOPERATIVE
PINPOINT TEST F: THE HEADLAMPS ARE ON CONTINUOUSLY
Test Step Result / Action to Take
E1 CHECK THE VOLTAGE TO THE INOPERATIVE HEADLAMP
BULB z
Key in OFF position.
z Disconnect: Inoperative Headlamp.
z Place the headlamp switch in the ON position.
z Place the multifunction switch in the high beam position.
z Measure the voltage between LH headlamp C1021 Pin 2,
Circuit 12 (LG/BK), or RH headlamp C1041 Pin 2, Circuit 12
(LG/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
INSTALL a new headlamp
bulb; REFER to
Bulb —
Headlamp in this section.
TEST the system for
normal operation.
No
REPAIR the circuit. TEST
the system for normal
operation. Test Step Result / Action to Take
F1 CHECK THE HEADLAMP SWITCH
z
Key in OFF position.
z Disconnect: Headlamp Switch C205.
z Are the headlamps on? Yes
GO to
F2 .
No
INSTALL a new headlamp
switch; REFER to Lamp Switch — Headlamp in this
section. TEST the system for
normal operation. F2 CHECK THE MULTIFUNCTION SWITCH
z
Disconnect: Multifunction Switch C202a.
z Are the headlamps on? Yes
GO to
F4 .
No
GO to F3 .
F3 CHECK CIRCUIT 15 (RD/YE) FOR SHORT TO POWER
z
Measure the voltage between multifunction switch
C202a Pin 15, Circuit 15 (RD/YE), harness side and
ground. Yes
REPAIR the circuit. TEST the
system for normal operation.
No
INSTALL a new multifunction
switch; REFER to
Section 211 -
05 . TEST the system for
normal operation. Klj . 6 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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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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