key FORD MUSTANG 2003 Workshop Manual

Battery—
Drain Tests
NOTE: No production vehicle should have more than a 50 mA (0.050 amp) continuous draw.
Check for current drains on the battery in excess of 50 milliamps (0.050 amp) with all the electrical
accessories off and the vehicle at rest. Current drains can be tested with the following procedure:
WARNING: Do not attempt this test on a lead- acid battery that has recently been
recharged. Explosive gases can cause personal injury.
CAUTION: To prevent damage to the meter, do not crank the engine or operate
accessories that draw more than 10A.
NOTE: Many modules draw 10 mA (0.010 amp) or more continuously.
NOTE: Use an in- line ammeter between the battery positive or negative post and its respective cable.
NOTE: Typically, a drain of approximately one amp can be attributed to an engine compartment lamp,
glove compartment lamp, or luggage compartment lamp staying on continually. Other component
failures or wiring shorts may be located by selectively pulling fuses to pinpoint the location of the
current drain. When the current drain is found, the meter reading will fall to an acceptable level. If the
drain is still not located after checking all the fuses, it may be due to the generator.
NOTE: To accurately test the drain on a battery, an in- line digital ammeter must be used. Use of a test
lamp or voltmeter is not an accurate method due to the number of electronic modules.
1. Make sure the junction box/fuse panels are accessible without turning on interior and underhood lights.
2. Drive the vehicle at least five minutes and over 48 km/h (30 mph) to turn on and exercise vehicle systems.
3. Allow the vehicle to sit with the key off for at least 40 minutes to allow modules to time out/power down.
4. Connect a fused jumper wire between the negative battery cable and the negative battery post to prevent modules from resetting and to catch capacitive drains.
5. Disconnect the negative battery cable from the post without breaking the connection of the jumper wire.
6. NOTE: It is very important that continuity is not broken between the battery and the negative
battery cable when connecting the meter. If this happens, the entire procedure must be
repeated.
Connect the tester between the negative battery cable and the post. The meter must be capable
of reading milliamps and should have a 10 amp capability.
7. NOTE: If the meter settings need to be switched or the test leads need to be moved to another
jack, the jumper wire must be reinstalled to avoid breaking continuity.
Remove the jumper wire.
NOTE: Amperage draw will vary from vehicle to vehicle depending on the equipment package.
Compare to a comparable vehicle for reference.
NOTE: No production vehicle should have more than a 50 mA (0.050 amp) draw. Klj . 11 ba
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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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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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PINPOINT TEST C: CONTINUOUS SEEK/SCAN IN AM/FM
PINPOINT TEST D: NO SOUND FROM ONE OR MORE OF THE
SPEAKERS —
NOT ALL SPEAKERS z
Is the noise eliminated? jumper cable. When noise is eliminated,
PROVIDE a permanent ground where
necessary. TEST the system for normal
operation.
Test Step Result / Action to Take
C1 CHECK OPERATION OF THE
SEEK/SCAN FUNCTIONS z
Key in ON position.
z Operate the SEEK/SCAN functions
with the audio unit in both AM and FM
tuner modes.
z Do the SEEK/SCAN functions
search continuously? Yes
GO to
C2 .
No
The system is OK. C2 CHECK ANTENNA FOR DAMAGE
z
Key in OFF position.
z Disconnect: Antenna Lead Terminal.
z Measure the resistance between the
antenna cable lead terminal and the
end of the antenna grid wire.
z Is the resistance less than 8 ohms? Yes
GO to
C3 .
No
REPAIR the antenna. REFER to Section 415 - 02
C3 SUBSTITUTE ANTENNA EXTENSION
CABLE z
Substitute a known good antenna
cable between the audio unit and the
antenna.
z Key in START position.
z Check the operation of the audio unit.
z Is the noise eliminated? Yes
INSTALL a new antenna extension cable. REFER
to
Section 415 - 02 . TEST the system for normal
operation.
No
REINSTALL the original cable. REMOVE the
audio unit and SEND it to an authorized Ford
audio system repair facility. TEST the system for
normal operation. Test Step Result / Action to
Take D1 CHECK FOR SOUND
z
Key in ON position.
z Turn on the audio unit.
z Are all speakers without sound? Yes
GO to
Pinpoint Test E .
No
For convertible,
GO to D2 .
For coupe, GO to
D4 . Klj . 7 ba
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affected speaker(s) and between the subwoofer amplifier and ground
as follows:
z Are the resistances less than 5 ohms between the subwoofer
amplifier and affected speaker(s) and greater than 10,000 ohms
between the subwoofer amplifier and ground? Speaker Circuits Affected Speaker Pin Subwoofer Amplifier Pin Circuit
RR 1 7 822 (BK/LG)
RR 2 8 287 (BK/WH)
LR 1 7 822 (BK/LG)
LR 2 8 287 (BK/WH) No
REPAIR the circuit
(s) in question.
TEST the system
for normal
operation.
D5 CHECK CIRCUITS BETWEEN THE AUDIO UNIT AND THE
SUBWOOFER AMPLIFIER z
Disconnect: Audio Unit C290b.
z Disconnect: Subwoofer Amplifier C4109b.
z Measure the resistance between the subwoofer amplifier C4109b pin
5, circuit 169 (LG/BK), harness side and the audio unit C290a pin 6,
circuit 169 (LG/BK), harness side and between the subwoofer
amplifier C4109b pin 5, circuit 169 (LG/BK), harness side and
ground; and between the subwoofer amplifier C4109b pin 6, circuit
172 (LB/RD), harness side and the audio unit C290a pin 5, circuit
172 (LB/RD), harness side and between the subwoofer amplifier
C4109b pin 6, circuit 172 (LB/RD), harness side and ground.
z Are the resistances less than 5 ohms between the subwoofer
amplifier and the audio unit and greater than 10,000 ohms
between the subwoofer amplifier and ground? Yes
GO to
D6 .
No
REPAIR the circuit
(s) in question.
TEST the system
for normal
operation. D6 CHECK SPEAKER(S)
z
Key in OFF position.
z Substitute the affected speaker with a known good component.
z Key in ON position.
z Turn on the audio unit.
z Is the affected speaker(s) operational? Yes
INSTALL a new
speaker. TEST the
system for normal
operation.
No
GO to
D7 .
D7 CHECK THE AUDIO UNIT
z
Key in OFF position.
z Substitute the affected audio unit with a known good component.
z Key in ON position.
z Turn on the audio unit.
z Is the affected speaker(s) operational? Yes
SEND the audio
unit to an
authorized Ford
audio system
repair facility.
TEST the system
for normal
operation.
No
REMOVE the
subwoofer
amplifier and
SEND it to an
authorized Ford
audio system
repair facility.
TEST the system Klj . 9 ba
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for normal
operation.
D8 CHECK FOR POWER TO THE AFFECTED SUBWOOFER
AMPLIFIER z
Key in OFF position.
z Disconnect: Mach 1000 Affected Subwoofer Amplifier.
z Measure the voltage between affected subwoofer amplifier pin 5,
circuit 828 (VT/LB) (left amplifiers) and ground, or between pin 5,
circuit 829 (WH/VT) (right amplifiers) and ground.
z Is the voltage greater than 10 volts? Yes
GO to
D9 .
No
REPAIR the circuit
(s) in question.
TEST the system
for normal
operation. D9 CHECK FOR GROUND TO THE AFFECTED SUBWOOFER
AMPLIFIER z
NOTE: Ground circuit 694 is located in the same cavity in all four
subwoofer amplifiers.
z Measure the resistance between affected subwoofer amplifier pin 2,
circuit 694 (BK/LG) and ground.
z Is the resistance less than 5 ohms? Yes
GO to
D10 .
No
REPAIR the circuit
(s) in question.
TEST the system
for normal
operation. D10 CHECK FOR AN AUDIO SIGNAL TO THE AFFECTED
SUBWOOFER AMPLIFIER z
Key in ON position.
z NOTE: Audio signal circuits 169 and 172 are located in the same
cavity on all four subwoofer amplifiers.
z Turn on the audio unit and check for a fluctuating AC voltage
between affected subwoofer amplifier pin 8, circuit 172 (LB/RD) and
pin 7, circuit 169 (LG/BK). Yes
GO to
D12 .
No
GO to D11 . Klj . 10 ba
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z
Does the voltage vary as the volume is adjusted? D11 CHECK AUDIO SIGNAL CIRCUITS AT THE AFFECTED
SUBWOOFER AMPLIFIER FOR OPEN AND SHORT TO GROUND z
Key in OFF position.
z Disconnect: Audio Unit C290a.
z Measure the resistance between the affected subwoofer amplifier
and the audio unit C290a, and between the affected subwoofer
amplifier and ground as follows:
z Is the resistance less than 5 ohms between the audio unit and
subwoofer amplifier and greater that 10,000 ohms between the
subwoofer amplifier and ground? Speaker Circuits Audio Unit C290a Pin Subwoofer Amplifier Pin Circuit
2 8 172 (LB/RD)
8 7 169 (LG/BK) Yes
SEND the audio
unit to an
authorized Ford
audio system
repair facility.
TEST the system
for normal
operation.
No
REPAIR the circuit
(s) in question.
TEST the system
for normal
operation.
D12 CHECK FOR AN AUDIO SIGNAL AT THE AFFECTED
SUBWOOFER z
Key in OFF position.
z Connect: Affected Subwoofer Amplifier.
z Disconnect: Affected Subwoofer Speaker .
z Key in ON position.
z Turn on the audio unit and check for a fluctuating AC voltage
between affected subwoofer as follows: For right subwoofer pin 4,
circuit 187 (DB/OG) and pin 2, circuit 189 (LG/BK) harness side; and
between pin 3, circuit 179 (OR/RD) and pin 1, circuit 176 (PK/LG)
harness side. For left subwoofer pin 1, circuit 187 (DB/OR) and pin 3,
circuit 189 (LG/BK) harness side; and between pin 2, circuit 179
(OR/RD) and pin 4, circuit 176 (PK/LG) harness side.
z Does the voltage vary as the volume is adjusted? Yes
INSTALL a new
subwoofer
speaker.
No
GO to
D13 .
D13 CHECK FOR AN OPEN AND SHORT TO GROUND BETWEEN THE
AFFECTED SUBWOOFER AND ITS RESPECTIVE AMPLIFIERS z
Key in OFF position. Yes Klj . 11 ba
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PINPOINT TEST E: NO SOUND FROM ALL OF THE SPEAKERS z
Disconnect: Respective Amplifier to Subwoofer Speaker Connector.
z Measure the resistance between the affected subwoofer speaker and
its respective amplifiers, and between the affected subwoofer
speaker and ground as follows:
z Is the resistance less than 5 ohms between the amplifier and
subwoofer speaker and greater that 10,000 ohms between the
subwoofer speaker harness and ground? Speaker Circuits—
Right Side Affected Subwoofer
Speaker Pin Respective Amplifier
Pin Circuit
1 4 176
(PK/LG) 3 3 179
(OR/RD) 2 4 189
(TN/LB) 4 3 187
(DB/OR)
Speaker Circuits— Left Side Affected Subwoofer
Speaker Pin Respective Amplifier
Pin Circuit
1 4 176
(PK/LG) 3 3 179
(OR/RD) 2 4 189
(TN/LB) 4 3 187
(DB/OR) INSTALL a new
subwoofer
amplifier.
No
REPAIR the circuit
(s) in question.
TEST the system
for normal
operation.
Test Step Result / Action to Take
E1 CHECK FOR AUDIO UNIT
OPERATION z
Key in ON position.
z Turn the audio unit on.
z Does the audio unit
display illuminate? Yes
GO to
E2 .
No
GO to Pinpoint Test A .
E2 CHECK THE SPEAKER
OPERATION z
Check the operation of all
speakers.
z Are all speakers
inoperative? Yes
REMOVE the audio unit and SEND it to an authorized Ford
audio system repair facility. TEST the system for normal
operation. Klj . 12 ba
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