2003 FORD MUSTANG headlamp

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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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
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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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Pinpoint Tests
PINPOINT TEST L: THE PARKING, REAR OR LICENSE LAMPS ARE
INOPERATIVE
PINPOINT TEST M: ONE OR MORE PARKING, REAR OR LICENSE
LAMP(S) IS INOPERATIVE
Test Step Result / Action to Take
L1 CHECK THE VOLTAGE TO THE HEADLAMP SWITCH
z
Disconnect: Headlamp Switch C205.
z Measure the voltage between headlamp switch C205 Pin
B2, Circuit 195 (TN/WH), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
L2 .
No
REPAIR the circuit. TEST the
system for normal operation. L2 CHECK CIRCUIT 14 (BN) FOR OPEN
z
Measure the resistance between headlamp switch C205
Pin R, Circuit 14 (BN), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new headlamp
switch; REFER to
Lamp Switch — Headlamp . TEST the
system for normal operation.
No
REPAIR the circuit. TEST the
system for normal operation. Test Step Result / Action to Take
M1 CHECK THE VOLTAGE TO THE INOPERATIVE
LAMP(S) z
Key in OFF position.
z Disconnect: Inoperative Lamp.
z Place the headlamp switch in the parking lamps
ON position.
z Measure the voltage between inoperative lamp
connector Circuit 14 (BN), harness side and
ground.
z Is the voltage greater than 10 volts? Yes
REPAIR Circuit 1205 (BK) for an open.
TEST the system for normal operation.
No
REPAIR the circuit. TEST the system
for normal operation. Klj . 2 ba
32003 Mustang Workshop Manual
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PINPOINT TEST N: THE PARKING, REAR OR LICENSE LAMPS ARE
ON CONTINUOUSLY
Test Step Result / Action to Take
N1 CHECK THE HEADLAMP
SWITCH z
Key in OFF position.
z Disconnect: Headlamp
Switch C205.
z Key in ON position.
z Are the parking, rear or
licences lamps on? Yes
REPAIR Circuit 14 (BN) for a short to battery. TEST the
system for normal operation.
No
INSTALL a new headlamp switch; REFER to
Lamp Switch — Headlamp . TEST the system for normal operation. Klj . 3 ba
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