2003 FORD MUSTANG high 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
42003 Mustang Workshop Manual
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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
42003 Mustang Workshop Manual
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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
412003 Mustang Workshop Manual
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PINPOINT TEST Q: THE HIGH BEAM INDICATOR IS
NEVER/ALWAYS ON z
Key in OFF position.
z Disconnect: Generator C102c.
z Key in ON position.
z Does the charging system indicator illuminate? Yes
GO to
P6 .
No
INSTALL a new generator.
REFER to Section 414 - 02 .
TEST the system for normal
operation. P6 CHECK CIRCUIT 904 (LG/RD) FOR SHORT TO GROUND
z
Key in OFF position.
z Measure the resistance between the generator C102c pin 1,
circuit 904 (LG/RD), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
P7 .
No
REPAIR the circuit. TEST
the system for normal
operation. P7 CHECK FOR CORRECT INSTRUMENT CLUSTER
OPERATION z
Disconnect all instrument cluster connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster connectors and make sure
they seat correctly.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new instrument
cluster. REFER to
Instrument Cluster
in this
section. TEST the system
for normal operation.
No
The system is operating
correctly at this time.
Concern may have been
caused by a loose or
corroded connector.
CLEAR the DTCs. REPEAT
the self- test. Test Step Result / Action to Take
Q1 CHECK THE HIGH BEAM LAMP OPERATION
CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector.
z Key in ON position.
z Operate the high beams.
z Do the high beams operate correctly? Yes
GO to
Q2 .
No
REFER to Section 417 - 01 .
Q2 CHECK CIRCUIT 932 (GY/WH) AND CIRCUIT 12 (LG/BK)
FOR AN OPEN Klj . 33 ba
412003 Mustang Workshop Manual
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PINPOINT TEST R: THE ABS WARNING INDICATOR IS NEVER ON z
Key in OFF position.
z Disconnect: Instrument Cluster C220b.
z Key in ON position.
z Measure the voltage between the instrument cluster C220b
pin 2, circuit 12 (LG/BK), harness side and ground, while
turning the high beams on and off.
z Is the voltage 0 volts with the high beams off and
greater than 10 volts with the high beams on? Yes
GO to
Q3 .
No
REPAIR the circuit. TEST
the system for normal
operation. Q3 CHECK FOR CORRECT INSTRUMENT CLUSTER
OPERATION z
Disconnect all instrument cluster connectors.
z Check for:
zcorrosion
z pushed- out pins
z Connect all instrument cluster connectors and make sure
they seat correctly.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new instrument
cluster. REFER to
Instrument Cluster
in this
section. TEST the system
for normal operation.
No
The system is operating
correctly at this time.
Concern may have been
caused by a loose or
corroded connector. CLEAR
the DTCs. REPEAT the self-
test. Test Step Result / Action to Take
R1 CHECK THE ABS WARNING INDICATOR OPERATION
CAUTION: Use the correct probe adapter(s) when
making measurements. Failure to use the correct probe
adapter(s) may damage the connector.
z Key in ON position.
z Observe the ABS warning indicator. The ABS indicator
should prove out for approximately six seconds then turn off.
z Does the ABS warning indicator operate correctly? Yes
The system is operating
normally at this time.
No
If the indicator is
inoperative, GO to
R2 .
If the indicator is always
on, REFER to Section 206 -
09A or
Section 206 - 09B .
R2 CHECK THE INSTRUMENT CLUSTER INPUT
z
Key in OFF position.
z Disconnect: Anti- Lock Brake Control Module C135.
z Connect a fused (10A) jumper wire between the anti- lock
brake control module C135 pin 16, circuit 603 (DG), harness Yes
REFER to
Section 206 - 09A
or
Section 206 - 09B . Klj . 34 ba
412003 Mustang Workshop Manual
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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
142003 Mustang Workshop Manual
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