2003 FORD MUSTANG high beam

4. With the engine running, turn the A/C on, the blower motor on high speed and the headlamps
on high beam.
5. Increase the engine speed to approximately 2,000 rpm. The voltage should increase a minimum of 0.5 volt above the base voltage.
zIf the voltage does not increase as specified, carry out the Generator On- Vehicle Tests—
No Load Test. For additional information, refer to Generator On- Vehicle Tests in this
section.
z If the voltage increases as specified, the charging system is operating normally.
6. With the engine running at 2,000 rpm, adjust the tester load bank to determine the output of the generator. Generator output should be at least 58 amps.
Generator On- Vehicle Tests— No Load Test
1. Switch the battery tester to the voltmeter function.
2. Connect the voltmeter positive lead to the generator B+ output terminal, circuit 38 (BK/OG) and the negative lead to ground.
3. Turn all electrical accessories off.
4. With the engine running at 2,000 rpm, check the generator output voltage. The voltage should be between 13.0 and 15.0 volts. If not, refer to the Symptom Chart. Klj . 13 ba
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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 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 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
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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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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DIAGNOSIS AND TESTING
Daytime Running Lamps (DRL)
Refer to Wiring Diagrams Cell
97 , Daytime Running Lamps for schematic and connector information.
Principles of Operation
Daytime Running Lamps (DRL)
The daytime running lamps (DRL) system operates the low beam headlamps at a reduced intensity.
The DRL module (15A270) supplies pulse width modulated (PWM) voltage, approximately 75%- 92%
of battery voltage, to the low beam headlamps when the following conditions are met:
zThe parking brake control is released.
z The high beam headlamps are disabled.
z The ignition switch (11572) is in the RUN position.
The DRL module remains enabled when the low beam headlamps are turned on.
Inspection and Verification 1. Verify the customer concern by operating the system.
2. Visually inspect for obvious signs of mechanical and electrical damage.
3. Verify the headlamps are operating correctly. Correct any concerns before proceeding to the
SECTION 417-
04: Daytime Running Lamps 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter or
equivalent
105-
R0057
Visual Inspection Chart Mechanical Electrical
z
Damaged DRL module
z Damaged parking brake signal switch and
bracket (15A851) z
Blown battery junction box (BJB) Maxi-
Fuse FOG+DRL (20A)
z Damaged wiring harness
z Loose or corroded connection
z Damaged DRL module
z Damaged parking brake signal switch and
bracket Klj . 1 ba
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