2003 FORD MUSTANG low beam

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 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
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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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GENERAL PROCEDURES
Headlamp Adjustment
Headlamp Aiming
1. The headlamp aiming procedure depends on the type of beam pattern the headlamp is equipped with. Vehicles may come equipped with visual optical right (VOR), visual optical left
(VOL), or SAE only (includes sealed beam type) headlamps. To identify the headlamp beam
pattern, look on the headlamp lens. Molded in small letters on the headlamp lens is one of the
following:
zSAE
z VOR or SAE
z VOL or SAE
2. Once the headlamp beam pattern is identified, aim the headlamps using one of the following methods as applicable.
zPhotometric aimers can aim SAE, VOR and VOL type headlamps. This is the preferred
method of headlamp aiming.
z Visual or screen method aiming can be used to aim SAE, VOR and VOL type
headlamps.
z Mechanical aimers can be used only with SAE type headlamps. Lamps that can be
aimed mechanically will have three nibs molded into the lens of the lamp.
Photometric Aiming 1. For the photometric aiming procedure, refer to the appropriate photometric headlamp aimer instruction manual.
Screen Method Aiming
All headlamp types
NOTE: Horizontal aim is not necessary for VOR or VOL headlamps.
NOTE: Consult your state vehicle inspection manual for recommended tolerance ranges for visual
aiming.
NOTE: The sight shield may need to be positioned or removed for access to the adjusters.
1. Before starting headlamp adjustment: zCheck the tire inflation.
z Check that no other load is in the vehicle other than a half tank of fuel.
z Check that the headlamps are clean.
z Check for correct headlamp operation.
SECTION 417-
01: Exterior Lighting 2003 Mustang Workshop Manual Klj . 1 ba
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z
Check that the vehicle is on level ground.
z If the vehicle is equipped with air suspension, make sure that the switch is on.
2. NOTE: The vertical wall or screen must be a minimum of 2.4 meters (8 feet) wide.
Park the vehicle on a level surface approximately 7.6 meters (25 feet) from the vertical wall or
screen directly in front of it.
3. NOTE: The center of the lamp is marked by a 3 mm (0.12 in) circle on the headlamp lens.
Mark a horizontal reference line on the vertical wall or screen. 1. Measure the center of the headlamp height to ground and record.
2. Make a 2.4 meter (8 foot) horizontal mark (masking tape) on the vertical wall or screen at the same distance from the ground as previously recorded.
4. NOTE: This procedure should be done in a dark environment to effectively see the headlamp
beam pattern.
Turn on the low beam headlamps to illuminate the wall or screen and open the hood.
5. NOTE: For SAE type headlamps, the appearance of the beam pattern may vary between
vehicles.
On the wall or screen, locate the high intensity area of the beam pattern. Place the top edge of
the high intensity zone even with the horizontal reference line.
VOR type headlamps 6. NOTE: The appearance of the VOR beam pattern may vary between vehicles.
Identify at the top edge of this high intensity area a distinct horizontal cutoff in the beam pattern.
If the top edge of this cutoff is not even with the horizontal reference line, the headlamp beam will need to be adjusted. Klj . 2 ba
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VOL type headlamps
7. For VOL type headlamps, there will be a distinct cutoff in the left portion of the beam pattern. The edge of this cutoff should be positioned 50.2 mm (2 in) below the horizontal reference line.
1. Horizontal reference line.
2. Top edge of the beam pattern.
3. High intensity zone.
Mechanical Aiming 1. For the mechanical aiming procedure, refer to the appropriate mechanical headlamp aimer instruction manual. Klj . 3 ba
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