2003 FORD MUSTANG low beam

DESCRIPTION AND OPERATION
Instrument Cluster
The instrument cluster (10849) consists of the following components:
Instrument Cluster—
Base 3.8L Engine
SECTION 413-
01: Instrument Cluster 2003 Mustang Workshop Manual Item Part
Number Description
1 — Fuel gauge
2 — Engine coolant temperature gauge
3 — Speedometer
4 — Turn signal/hazard indicator
5 — High beam indicator
6 — Tachometer
7 — Odometer
8 — Trip odometer reset button
9 — Voltmeter gauge
10 — Oil pressure gauge
11 — CHECK FUEL CAP indicator
12 — BRAKE warning indicator
13 — ABS warning indicator
14 — Traction control indicator
15 — Overdrive off (O/D OFF) indicator (automatic Klj . 1 ba
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Instrument Cluster—
Base 4.6L Engine transmission)
16 — LOW FUEL level indicator
17 — SERVICE ENGINE SOON indicator
18 — THEFT indicator
19 — AIR BAG warning indicator
20 — Charging system indicator
21 — Safety belt warning indicator
Item Part
Number Description
1 — Fuel gauge
2 — Engine coolant temperature gauge
3 — Speedometer
4 — Turn signal/hazard indicator
5 — High beam indicator
6 — Tachometer
7 — Odometer
8 — Trip odometer reset button
9 — Voltmeter gauge
10 — Oil pressure gauge
11 — CHECK FUEL CAP indicator
12 — BRAKE warning indicator
13 — ABS warning indicator Klj . 2 ba
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Instrument Cluster—
Cobra 14 — Traction control indicator
15 — Overdrive off (O/D OFF) indicator (automatic
transmission)
16 — LOW FUEL level indicator
17 — SERVICE ENGINE SOON indicator
18 — THEFT indicator
19 — AIR BAG warning indicator
20 — Charging system indicator
21 — Safety belt warning indicator
Item Part
Number Description
1 — Fuel gauge
2 — Engine coolant temperature gauge
3 — Speedometer
4 — Turn signal/hazard indicator
5 — High beam indicator
6 — Tachometer
7 — Odometer
8 — Trip odometer reset button
9 — Boost gauge
10 — Oil pressure gauge
11 — CHECK FUEL CAP indicator
12 — BRAKE warning indicator Klj . 3 ba
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The boost pressure gauge on the instrument cluster receives and measures the boost pressure
directly from the intake manifold. The boost pressure gauge will display between 0.0-
0.48 kpa (0.0-10
psi) boost pressure dependent upon accelerator position, engine load, and engine rpm.
LOW FUEL Level Indicator
The low fuel level indicator is hardwired from the fuel sender to the instrument cluster. The instrument
cluster will illuminate the low fuel indicator when the usable fuel quantity is less than 1/8 tank (15%) of
fuel tank capacity.
Oil Pressure Gauge
The oil pressure gauge is hardwired from the oil pressure switch to the instrument cluster. The oil
pressure gauge will indicate either normal or no oil pressure.
CHECK FUEL CAP
The CHECK FUEL CAP indicator is used to indicate significant leaks in the fuel tank evaporative
system due to a loose fuel cap. Fuel tank pressure is monitored by the PCM. If a leak is detected the
PCM signals a fault to the instrument cluster via the SCP network. Once the PCM has detected a
loose fuel cap and the CHECK FUEL CAP indicator is illuminated, the indicator will remain illuminated
until the fuel cap is secured and the vehicle has been running for several minutes. For additional
information, refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
BRAKE Warning Indicator
The BRAKE warning indicator activates when the generic electronic module (GEM) detects the ignition
switch circuits are in the RUN state, when the GEM detects low brake fluid level, or that the parking
brake is applied. The BRAKE warning indicator will prove out starting when the GEM detects that the
ignition circuits have made a transition to RUN or START from OFF, ACC, or keyout and ending when
either three seconds have elapsed or when the GEM detects the ignition circuits have made a
transition to OFF, ACC, or keyout.
Safety Belt Warning Indicator
The safety belt switch is hardwired to the GEM. The safety belt warning indicator will be illuminated
when the GEM sends a ground signal to the instrument cluster.
ABS Warning Indicator
The ABS warning indicator will be illuminated when the anti- lock brake control module sends a ground
signal to the instrument cluster. The prove- out of the ABS indicator is controlled by the anti- lock brake
control module.
SERVICE ENGINE SOON Indicator
The SERVICE ENGINE SOON indicator receives its signal from the PCM over the SCP network. If the
instrument cluster does not receive a message from the PCM within five seconds, the instrument
cluster will illuminate the SERVICE ENGINE SOON indicator and log a diagnostic trouble code (DTC).
High Beam Indicator
The high beam indicator will illuminate when the steering column multifunction switch is in the high
beam position by sending a battery signal to the instrument cluster. Right and Left Turn Indicator Klj . 3 ba
412003 Mustang Workshop Manual
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z
Powertrain
control module
(PCM). manual.
z The CHECK FUEL CAP
INDICATOR is never on z
Circuitry.
z Standard
corporate
protocol (SCP)
network.
z Powertrain
control module
(PCM). z
Go To Pinpoint Test N .
z The CHECK FUEL CAP
INDICATOR is always
on z
Circuitry.
z Powertrain
control module
(PCM).
z Fuel system. z
REFER to the Powertrain
Control/Emissions
Diagnosis (PC/ED)
manual.
z The BRAKE warning
indicator is never/always
on z
Circuitry.
z Low brake fluid
level.
z Brake fluid
level switch.
z Parking brake
switch.
z Instrument
cluster.
z Generic
electronic
module (GEM). z
Go To Pinpoint Test O .
z The charging system
warning indicator is
never/always on z
Circuitry.
z Generator.
z Charging
system warning
indicator bulb.
z Instrument
cluster. z
Go To Pinpoint Test P .
z The high beam indicator
is never/always on z
Circuitry.
z High beam
indicator bulb.
z Instrument
cluster. z
Go To Pinpoint Test Q .
z The air bag warning
indicator is never/always
on z
Circuitry.
z Air bag warning
indicator bulb.
z Instrument
cluster.
z Restraint
control module
(RCM). z
REFER to Section 501 -
20B .
z The anti- lock brake
system (ABS) warning
indicator is never on z
Circuitry.
z ABS warning
indicator bulb.
z Anti- lock brake
control module.
z Instrument
cluster. z
Go To Pinpoint Test R .
z The ABS warning
indicator is always on z
Circuitry.
z Anti- lock brake
control module. z
REFER to Section 206 -
09A or
Section 206 - 09B . Klj . 12 ba
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PINPOINT TEST H: RADIO INTERFERENCE
Component Tests
Battery—Load Test
1. With the engine running, turn the A/C on, the blower motor on high speed and the headlamps on high beam.
2. 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.
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. NOISE
z
Disconnect: Generator C102c (4.6L 4V) or
C102a (3.8L or 4.6L 2V).
z Key in START position.
z With the engine running, turn the headlights
on, rear defroster on, and the blower motor to
the HI position.
z Is the noise still present? Yes
GO to
G4 .
No
INSTALL a new generator. REFER to
Section 414 - 02 . TEST the system for
normal operation. G4 CHECK GENERATOR FOR MECHANICAL
NOISE z
Key in OFF position.
z Connect: Generator C102c (4.6L 4V) or C102a
(3.8L or 4.6L 2V).
z Key in START position.
z Turn all accessories off. With the engine
running, use a stethoscope or equivalent
listening device to probe the generator for
unusual mechanical noise.
z Is the generator the noise source? Yes
INSTALL a new generator. REFER to
Section 414
- 02 . TEST the system for
normal operation.
No
REFER to Section 303 - 00 to diagnose
the source of engine noise. Test Step Result / Action to Take
H1 VERIFY GENERATOR IS SOURCE OF
RADIO INTERFERENCE z
Key in START position.
z With the engine running, tune the radio to
a station where the interference is present.
z Key in OFF position.
z Disconnect: Generator C102c (4.6L 4V) or
C102a (3.8L or 4.6L 2V).
z Key in START position.
z With the engine running, note any radio
interference.
z Is the interference present with the
generator disconnected? Yes
REFER to
Section 415 - 00 for diagnosis and
testing of the in- vehicle entertainment
system.
No
INSTALL a new generator. REFER to
Section 414 - 02 . TEST the system for normal
operation. Klj . 10 ba
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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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DIAGNOSIS AND TESTING
Headlamps
Refer to Wiring Diagrams Cell
85 , Headlamps for schematic and connector information.
Inspection and Verification 1. Verify the customer concern by operating the headlamps.
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)
73III Automotive Meter or
equivalent
105-
R0057
Visual Inspection Chart Mechanical Electrical
z
Damaged headlamp switch (11654)
z Damaged multifunction switch (13K359) z
Battery junction box (BJB) fuse 2 (30A)
z Central junction box (CJB) fuse(s):
„38 (20A)
„ 4 (7.5A) (RH)
„ 10 (7.5A) (LH)
z Damaged wiring harness
z Loose or corroded connections
z Headlamp bulb
Symptom Chart Condition
Possible Sources Action
z Both
headlamps are
inoperative z
Battery junction
box (BJB) fuse 2
(30A).
z Headlamp
switch.
z Circuitry.
z Multifunction
switch. z
Go To Pinpoint Test A .
z The low beams
are inoperative z
Circuitry.
z Multifunction
switch. z
Go To Pinpoint Test B . Klj . 1 ba
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