2003 FORD MUSTANG audio

REMOVAL AND INSTALLATION
Plenum Chamber
Removal
1. Remove the instrument panel. For additional information, refer to Section 501 - 12 .
2. Remove the audio unit. For additional information, refer to Section 415 - 01 .
3. If equipped, remove the CD player. For additional information, refer to Section 415 - 01 .
4. Remove the instrument panel center finish panel screws.
5. Remove the instrument panel center finish panel screw.
6. Unsnap and remove the instrument panel center finish panel.
7. Remove the screws and remove the defroster duct.
SECTION 412-
01: Air Distribution and Filtering 2003 Mustang Workshop Manual Klj . 1 ba
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DESCRIPTION AND OPERATION
Instrument Cluster and Panel Illumination
The instrument cluster and panel illumination system illuminates the following components:
zinstrument cluster (10849)
z audio unit (18806)
z A/C- heater control
z fog lamp switch
z transmission range indicator
z traction control switch
z rear window defrost control switch
The instrument cluster is a hybrid electronic cluster (HEC), which uses both hardwired circuitry and the
standard corporate protocol (SCP) communication network to transmit and receive information. The
Mustang instrument cluster backlighting has illumination bulbs that are installed separately from the
instrument cluster. The Cobra instrument cluster has a laminated, electroluminescent applique to
backlight the cluster . The electroluminescent applique and instrument cluster must be installed as an
assembly. SECTION 413-
00: Instrument Cluster and Panel Illumination 2003 Mustang Workshop Manual Klj . 1 ba
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Pinpoint Tests
PINPOINT TEST A: THE CONTROL ILLUMINATION IS INOPERATIVE
PINPOINT TEST B: THE INSTRUMENT CLUSTER ILLUMINATION IS
INOPERATIVE z
Bulb(s).
z The climate control
illumination is inoperative z
Circuitry.
z Bulb(s). z
Go To Pinpoint Test C .
z The audio system
illumination is inoperative z
Circuitry.
z Audio unit. z
Go To Pinpoint Test D .
z A single illumination source
is inoperative z
Circuitry.
z Switch. z
Go To Pinpoint Test E .
Test Step Result / Action to Take
A1 CHECK PARKING LAMPS
z
Place the headlamp switch in the ON
position.
z Are the exterior lamps on? Yes
Place the headlamp switch in the OFF position.
GO to
A2 .
No
REFER to Section 417 - 01 .
A2 CHECK HEADLAMP SWITCH
z
Key in OFF position.
z Carry out the headlamp switch
components test;
Refer to Wiring Diagrams Cell 149 for
schematic and connector information.
.
z Is the headlamp switch OK? Yes
RECONNECT the headlamp switch. GO to
A3 .
No
INSTALL a new headlamp switch. REFER to
Section 417 - 01 . TEST the system for normal
operation. A3 CHECK CIRCUIT 1045 (DB/WH)
z
Place the headlamp switch in the ON
position.
z Rotate the instrument panel dimmer
switch to the full illumination position.
z Measure voltage between central
junction box (CJB) fuse 37 (5A) and
ground.
z Is the voltage greater than 10 volts? Yes
REPAIR circuit 19 (LB/RD). TEST the system for
normal operation.
No
REPAIR circuit 1045 (DB/WH). TEST the system
for normal operation.
Test Step Result / Action to Take
B1 CHECK VOLTAGE TO INSTRUMENT CLUSTER
ILLUMINATION z
Disconnect: Instrument Cluster .
z Place the headlamp switch in the ON position.
z Rotate the instrument panel dimmer switch to the full Yes
GO to
B2 . Klj . 2 ba
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PINPOINT TEST D: THE AUDIO SYSTEM ILLUMINATION IS
INOPERATIVE z
Measure the resistance between the function selector switch
C294b pin 1, circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
INSTALL new
illumination bulb(s).
REFER to
Section 412 -
04 .
No
REPAIR the circuit.
TEST the system for
normal operation. Test Step Result / Action to Take
D1 CHECK VOLTAGE TO AUDIO UNIT
z
Disconnect: Audio Unit C290a.
z Place the headlamp switch in the ON position.
z Rotate the instrument panel dimmer switch to the full
illumination position.
z Measure the voltage between the audio unit C290a pin
1, circuit 19 (LB/RD), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
D2 .
No
REPAIR the circuit. TEST the
system for normal operation. D2 CHECK GROUND TO AUDIO UNIT
z
Measure the resistance between the audio unit C290a
pin 2, circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
REMOVE the audio unit and
SEND it to an authorized Ford
audio systems repair facility.
TEST the system for normal
operation.
No
REPAIR the circuit. TEST the
system for normal operation. Klj . 4 ba
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DIAGNOSIS AND TESTING
Audio System
Refer to Wiring Diagrams Cell
130 , Radio for schematic and connector information.
Inspection and Verification 1. Verify the customer concern by operating the electronic audio system with the engine running.
2. Visually inspect the following for obvious signs of mechanical and electrical damage.
3. If the concern remains and the fault is not detected, proceed to the Symptom Chart to continue diagnostics.
Symptom Chart SECTION 415-
00: Entertainment System — General Information 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter
105-
R0057 or equivalent
Visual Inspection Chart Mechanical Electrical
z
Audio unit
z Antenna or antenna cable
z Speakers mounting/speaker cones
z Radio ignition interference capacitor, radio frequency
interference suppression bond or radio receiver hood bonding
strap cleanliness z
Battery junction box
(BJB) fuses:
„3 (40A)
„ 4 (40A)
„ 6 (40A)
z Central junction box
(CJB) fuses:
„6 (20A)
„ 27 (25A)
„ 32 (15A)
z Ignition switch
z Circuitry
z Audio unit
Symptom Chart Condition
Possible Sources Action
z The audio unit is
inoperative/does not operate z
Central
junction box z
Go To Pinpoint Test A . Klj . 1 ba
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correctly
(CJB) fuses:
„6
(20A).
„ 27
(25A).
„ 32
(15A).
z Battery
junction box
(BJB) fuses:
„3
(40A).
„ 4
(40A).
„ 6
(40A).
z Circuitry.
z Audio unit.
z Ignition
switch.
z Audio unit display blank —
audio unit operates z
Audio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation.
z Tape player only inoperative zAudio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation.
z Poor reception zAntenna
connections.
z Antenna
cable.
z Noise
suppression
equipment.
z Audio unit.
z Generator.
z Ignition
system. z
Go To Pinpoint Test B .
z Poor reception — FM only zFM signal out
of range. z
INFORM customer
of methods for
obtaining best
reception.
z Continuous SEEK/SCAN in
AM/FM z
Antenna.
z Antenna
connections.
z Audio unit. z
Go To Pinpoint Test C .
z No sound from one or more of
the speakers — not all speakers z
Speaker(s).
z Circuitry.
z Audio unit.
z Subwoofer
amplifier. z
Go To Pinpoint Test D .
z No sound from all of the zAudio unit. zGo To Pinpoint Test Klj . 2 ba
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Pinpoint Tests speakers
zSubwoofer
amplifier.
z Circuitry. E .
z Poor quality sound from one or
more speakers (not all
speakers) z
Speaker(s).
z Circuitry.
z Audio unit.
z Subwoofer
amplifier. z
Go To Pinpoint Test F .
z Poor quality sound from all
speakers z
Audio unit.
z Speaker(s).
z Circuitry. z
Go To Pinpoint Test G .
z The subwoofer is inoperative zSubwoofer.
z Subwoofer
amplifier.
z Circuitry. z
Go To Pinpoint Test H .
z Loud popping when cycling the
ignition switch z
Audio unit.
z Circuitry. z
Go To Pinpoint Test I .
z One or more audio control
buttons (such as volume, seek,
tune and scan) are not
functional in either radio, tape,
or CD mode or all modes z
Audio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation.
z When the headlamp switch is in
park or headlamp position and
the ignition switch is in the RUN
or ACC position, the audio unit
back lighting is inoperative — all
other I/P lighting functions are
normal z
Circuitry.
z Audio unit. z
REFER to Section 413 - 00 .
z The audio unit has two items
that can be dimmed— the audio
unit display and the control
buttons; one dims and the other
does not z
Audio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation.
z Irregular operation of display
and indicator LEDs z
Audio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation.
z Response time between
pressing any of the audio
control buttons and system
response is more than two
seconds z
Audio unit. zREMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the
system for normal
operation. Klj . 3 ba
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PINPOINT TEST A: THE AUDIO UNIT IS INOPERATIVE/DOES NOT
OPERATE CORRECTLY
Test Step Result / Action to
Take A1 CHECK OPERATION OF THE AUDIO UNIT
z
Key in ON position.
z Turn on the audio unit.
z Is the audio unit display illuminated? Yes
GO to
A2 .
No
GO to A4 .
A2 CHECK FOR SOUND COMING FROM THE SPEAKERS
z
Verify that sound is coming from all the speakers.
z Is there sound coming from all the speakers? Yes
GO to
A3 .
No
GO to Pinpoint Test C .
A3 CHECK THE AUDIO UNIT CONTROLS AND FEATURES
z
Refer to the owner literature for audio system controls.
z Verify that the controls and features operate correctly.
z Do the controls and features operate correctly? Yes
System operation is
normal at this time.
No
REMOVE the audio
unit and SEND it to
an authorized Ford
audio system facility.
TEST the system for
normal operation.
A4 CHECK VOLTAGE AT THE AUDIO UNIT
z
Key in OFF position.
z Disconnect: Audio Unit C290b.
z Key in ON position.
z Measure the voltage between the audio unit C290b pin 10, circuit
1002 (BK/PK), harness side and ground, and between the audio
unit C290b pin 9, circuit 828 (VT/LB), harness side and ground.
z Are the voltages greater than 10 volts? Yes
GO to
A5 .
No
REPAIR the circuit
(s) in question. TEST
the system for
normal operation. A5 CHECK THE GROUND CIRCUITS TO THE AUDIO UNIT
z
Key in OFF position.
z Measure the resistance between the audio unit C290b pin 2, circuit
1205 (BK), harness side and ground; and between the audio unit
C290b pin 11, circuit 694 (BK/LG), harness side and ground; and
between the audio unit C290b pin 16, circuit 694 (BK/LG), harness
side and ground Yes
REMOVE the audio
unit and SEND it to
an authorized Ford
audio system repair
facility. TEST the Klj . 4 ba
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