Test G FORD MUSTANG 2003 Workshop Manual

8. If the draw is found to be excessive, pull fuses from the battery/central junction box one at a
time and note the current drop. Do not reinstall the fuses until you are finished testing.
9. Check the wiring schematic in the wiring diagram for any circuits that run from the battery without passing through the battery/central junction box. Disconnect these circuits if the draw is
still excessive.
Battery— Electronic Drains Which Shut Off When the Battery Cable is Disconnected
1. Repeat the steps of the battery drain testing.
2. Make sure all doors are closed and accessories are off. Without starting the engine, turn the ignition switch to RUN for a moment and then OFF. Wait a few minutes for the illuminated entry
lamps to turn off if equipped.
3. Connect the ammeter and read the amperage draw.
The current reading (current drain) should be less than 50 mA (0.05 amp). If the current drain exceeds
50 mA (0.05 amp) after a few minutes, and if this drain did not show in previous tests, the drain is most
likely caused by an inoperative electronic component. As in previous tests, remove the fuses from the
battery/central junction box one at a time to locate the problem circuit.
Generator On- Vehicle Tests
CAUTION: To prevent damage to the generator, do not make jumper wire connections
except as directed.
CAUTION: Do not allow any metal object to come in contact with the housing and the
internal diode cooling fins with key on or off. A short circuit will result and burn out the diodes.
NOTE: Battery posts and cable clamps must be clean and tight for accurate meter indications.
NOTE: Refer to the Battery Tester Procedure Manual for complete directions for testing the charging
system.
1. Turn off all lamps and electrical components.
2. Place the vehicle in transmission range NEUTRAL and apply the parking brake.
3. Carry out the Load Test and No- Load Test according to the following component tests:
Generator On- Vehicle Tests— Load Test
1. Switch the battery tester to the ammeter function.
2. Connect the positive and negative leads of the battery tester to the corresponding battery terminals.
3. Connect the current probe to the generator B+ output terminal, circuit 38 (BK/OG). Klj . 12 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
Battery
Inspection and Verification
1. Verify the customer concern by operating the system.
2. Visually inspect for obvious signs of mechanical or electrical damage.
3. If an obvious cause for a concern is found, correct the cause before proceeding to the next step.
4. If the fault is not visually evident, proceed to the pinpoint test.
Pinpoint Tests
PINPOINT TEST A: BATTERY CONDITION TEST SECTION 414-
01: Battery, Mounting and Cables 2003 Mustang Workshop Manual Special Tool(s)
Micro 490 Digital Battery
Analyzer
162-
00004
Visual Inspection Chart Mechanical Electrical
z
Battery
z Battery mounting z
Battery cables
z Battery posts Test Step Result / Action to Take
A1 TEST BATTERY CONDITION
NOTE:
No battery with a red test- eye should be
replaced. The red eye only means the battery is
discharged, not necessarily defective. NOTE: Failure
to fully charge the battery before retesting may cause
false readings.
z Verify the battery condition using the Battery
Analyzer.
z Is the battery OK? Yes
Does the meter read, GOOD
BATTERY? RETURN the battery
to service. REFER to
Section 414 -
00 .
Does the meter read, GOOD-
RECHARGE? CHARGE the
battery and RETURN to service.
REFER to Section 414 - 00 .
Does the meter read, CHARGE &
RETEST? Fully CHARGE the
battery and RETEST. Klj . 1 ba
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DIAGNOSIS AND TESTING
Generator
Refer to
Section 414 - 00 .
SECTION 414-
02: Generator and Regulator 2003 Mustang Workshop Manual Klj . 1 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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PINPOINT TEST B: POOR RECEPTION z
Are the resistances less than 5 ohms? system for normal
operation.
No
REPAIR the circuit
(s) in question. TEST
the system for
normal operation.
Test Step Result / Action to Take
B1 CHECK ANTENNA CABLE
CONNECTIONS z
Key in OFF position.
z Check the antenna connections
including the extension cable.
z Check to make sure the antenna is
securely mounted to the vehicle body
at ground points.
z Are the connections clean, secure,
and in metal- to-metal contact? Yes
GO to
B2 .
No
CLEAN and SECURE the antenna connections
as necessary. TEST the system for normal
operation. B2 CHECK SUPPRESSION
EQUIPMENT/MOUNTING AND
CONNECTING CIRCUITS z
Check all necessary suppression
equipment and the radio frequency
interference suppression bond. Refer
to Section 415 - 01 .
z Check the radio receiver hood bonding
strap and the body- to-chassis straps
for integrity, cleanliness, and metal- to-
metal contact.
z NOTE: The capacitor mounting points
are used to complete the electrical
circuit and must be mounted securely
to clean surfaces.
z Check the mounting and connecting
circuits of the radio ignition interference
capacitor for integrity, cleanliness, and
metal- to-metal contact.
z Are the connections clean, secure,
and in metal- to-metal contact? Yes
GO to
B3 .
No
CLEAN, SECURE, or INSTALL new suppression
equipment as necessary. TEST the system for
normal operation. B3 CHECK RADIO IGNITION
INTERFERENCE CAPACITOR z
Check the operation of the radio
ignition interference capacitor by
substituting it with a known good
component.
z Key in START position.
z Turn the audio unit on and check the
radio reception. Yes
INSTALL a new radio ignition interference
capacitor. TEST the system for normal operation.
No
GO to
B4 . Klj . 5 ba
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z
Is the noise eliminated? B4 CHECK GENERATOR
z
Key in OFF position.
z Check the generator by disconnecting
the wiring from the voltage regulator.
z Key in START position.
z Turn on the audio unit and check the
radio reception.
z Is the noise eliminated? Yes
INSTALL a new generator. REFER to
Section 414 - 02 . TEST the system for normal operation.
No
GO to B5 .
B5 CHECK IGNITION CIRCUITS
z
Key in OFF position.
z Check the ignition circuits for correct
routing, grounding, and integrity of
connections.
z Are the ignition components OK? Yes
GO to
B6 .
No
REPAIR the ignition system as necessary. TEST
the system for normal operation. B6 SUBSTITUTE ANTENNA
z
Substitute a known good antenna.
Ground the antenna base to an
unpainted metal surface on the vehicle.
z Key in START position.
z Verify the operation of the audio unit.
z Is the noise eliminated? Yes
INSTALL a new antenna. TEST the system for
normal operation.
No
GO to
B7 .
B7 SUBSTITUTE ANTENNA CABLE
z
Key in OFF position.
z Substitute a known good antenna
cable.
z Key in START position.
z Verify the operation of the audio unit.
z Is the noise eliminated? Yes
INSTALL a new antenna cable. TEST the system
for normal operation.
No
GO to
B8 .
B8 SUBSTITUTE AUDIO UNIT
z
Key in OFF position.
z Substitute a known good audio unit.
z Key in START position.
z Verify the operation of the audio unit.
z Is the noise eliminated? Yes
REMOVE the audio unit and SEND it to an
authorized Ford audio system repair facility.
TEST the system for normal operation.
No
GO to
B9 .
B9 SUBSTITUTE SUBWOOFER
AMPLIFIER z
Key in OFF position.
z Substitute a known good subwoofer
amplifier.
z Key in START position.
z Verify the operation of the audio unit.
z Is the noise eliminated? Yes
REMOVE the subwoofer amplifier and SEND it to
an authorized Ford audio system repair facility.
TEST the system for normal operation.
No
GO to
B10 .
B10 REPOSITION COMPONENTS
z
Key in OFF position.
z Determine if the noise can be
eliminated by repositioning the antenna
cable, speaker circuits, or audio unit
power feed circuits away from other
circuits or brackets.
z Key in START position.
z Verify the operation of the audio unit. Yes
Permanently REPOSITION the components as
needed. TEST the system for normal operation.
No
GROUND various parts (for example, engine,
fenders, quarter panels, stone deflectors, body
sheet metal) of the vehicle to the frame using a Klj . 6 ba
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