2003 FORD MUSTANG charging

LOW
PINPOINT TEST B: THE CHARGING SYSTEM WARNING INDICATOR
IS ON WITH THE ENGINE RUNNING (THE BATTERY VOLTAGE
DOES NOT INCREASE)
Test Step Result / Action to Take
A1 CHECK BATTERY CONDITION
z
Carry out the Battery— Condition Test to determine if
the battery can hold a charge and is OK for use.
Refer to Section 414 - 01 .
z Is the battery OK? Yes
GO to
A2 .
No
INSTALL a new battery. REFER
to Section 414 - 01 . TEST the
system for normal operation. A2 CHECK THE GENERATOR OUTPUT
z
Carry out the On- Vehicle Generator Load/No Load
Test. Refer to Component Tests in this section.
z Is the generator OK? Yes
GO to
A3 .
No
GO to Pinpoint Test B .
A3 CHECK FOR CURRENT DRAINS
z
Carry out the Battery— Drain Test. Refer to
Component Tests in this section.
z Are there any excessive current drains? Yes
REPAIR as necessary. TEST the
system for normal operation.
No
GO to
A4 .
A4 CHECK FOR CURRENT DRAINS WHICH SHUT OFF
WHEN THE BATTERY IS DISCONNECTED z
Carry out the Battery— Electronic Drains Which Shut
Off When the Battery Cable is Disconnected Test.
Refer to Component Tests in this section.
z Are there any current drains which shut off when
the battery is disconnected? Yes
REPAIR as necessary. TEST the
system for normal operation.
No
GO to
Pinpoint Test B .
Test Step Result / Action to
Take B1 CHECK GENERATOR B+ CIRCUIT 38 (BK/OG)
z
Disconnect: Generator B+ C102b.
z Measure the voltage between the generator C102b, circuit 38
(BK/OG), component side and ground. Yes
GO to
B2 .
No
REPAIR the circuit.
TEST the system for
normal operation. Klj . 5 ba
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PINPOINT TEST C: THE SYSTEM OVERCHARGES (THE BATTERY
VOLTAGE IS GREATER THAN 15.5 VOLTS)
PINPOINT TEST D: THE CHARGING SYSTEM WARNING INDICATOR
IS ON WITH THE ENGINE RUNNING AND THE BATTERY z
Is the voltage drop less than 0.5 volt? REPAIR high
resistance in the B+
circuit 38 (BK/OG).
TEST the system for
normal operation.
Test Step Result / Action to Take
C1 CHECK FOR VOLTAGE DROP IN A CIRCUIT 36 (YE/WH)
z
Disconnect: Generator C102c (4.6L 4V) or C102a (3.8L or 4.6L
2V).
z Key in ON position.
z Measure the voltage drop between the generator C102c (4.6L
4V) or C102a (3.8L or 4.6L 2V) pin 3, circuit 36 (YE/WH),
harness side and positive battery terminal.
z Is the voltage drop less than 0.5 volt? Yes
GO to
C2 .
No
REPAIR the high
resistance in A circuit 36
(YE/WH). TEST the
system for normal
operation. C2 CHECK GENERATOR AND BATTERY GROUND
CONNECTIONS z
Key in OFF position.
z Check the ground connections between the voltage regulator
and the generator and the engine, and the battery and the
engine.
z Are all ground connections clean and tight? Yes
INSTALL a new
generator. REFER to
Section 414
- 02 . TEST
the system for normal
operation.
No
REPAIR ground
connections as
necessary. TEST the
system for normal
operation. Klj . 7 ba
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INCREASES VOLTAGE
PINPOINT TEST E: THE CHARGING SYSTEM WARNING INDICATOR
IS OFF WITH THE IGNITION SWITCH IN THE RUN POSITION AND
THE ENGINE OFF
PINPOINT TEST F: THE CHARGING SYSTEM WARNING INDICATOR
LAMP FLICKERS OR IS INTERMITTENT
Test Step Result / Action to Take
D1 CHECK I CIRCUIT 904 (LG/RD) FOR A
SHORT TO GROUND z
Disconnect: Generator C102c (4.6L 4V) or
C102a (3.8L or 4.6L 2V).
z Key in ON position.
z With the ignition switch in the RUN position,
check the charging system warning
indicator.
z Is the charging system warning indicator
illuminated? Yes
REPAIR circuit 904 (LG/RD) for a short to
ground. TEST the system for normal
operation.
No
INSTALL a new generator. REFER to
Section 414
- 02 . TEST the system for
normal operation. Test Step Result / Action to
Take E1 CHECK THE CHARGING SYSTEM WARNING INDICATOR
LAMP z
Disconnect: Generator C102c (4.6L 4V) or C102a (3.8L or 4.6L
2V).
z With the engine off, connect a fused (15A) jumper wire between
the generator C102c (4.6L 4V) or C102a (3.8L or 4.6L 2V) pin 1,
circuit 904 (LG/RD), harness side and ground.
z Key in ON position.
z Is the charging system warning indicator lamp illuminated? Yes
INSTALL a new
generator. REFER to
Section 414
- 02 . TEST
the system for normal
operation.
No
REFER to Section 413 - 01 for diagnosis
and testing of the
instrument cluster. Test Step Result / Action to
Take F1 CHECK FOR LOOSE CONNECTIONS
z
Check all generator, battery, and power distribution connections
for looseness, corrosion, loose or bent terminals, or loose eyelets.
z Are all connections clean and tight? Yes
GO to
F2 .
No Klj . 8 ba
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PINPOINT TEST G: THE GENERATOR IS NOISY REPAIR as
necessary. TEST the
system for normal
operation.
F2 CHECK FUSE
z
Key in START position.
z With the engine running, check battery junction box (BJB) fuse 20
(20A) in circuit 36 (YE/WH) for looseness by wiggling the fuse and
noting the charging system warning indicator lamp operation.
z Does the charging system warning indicator lamp flicker? Yes
REPAIR loose fuse
connections as
necessary. TEST the
system for normal
operation.
No
GO to
F3 .
F3 CHECK A CIRCUIT 36 (YE/WH) CONNECTIONS
z
Key in OFF position.
z Connect a fused jumper wire between the generator C102c, (4.6L
4V) or C102a (3.8L or 4.6L 2V) pin 3, circuit 36 (YE/WH), harness
side and the positive battery terminal.
z Key in START position.
z With the engine running, note the charging system warning
indicator operation.
z Does the charging system warning indicator lamp flicker? Yes
REFER to
Section 414 - 02 . TEST the
system for normal
operation.
No
REPAIR loose
connection(s) in
circuits. TEST the
system for normal
operation. Test Step Result / Action to Take
G1 CHECK FOR ACCESSORY DRIVE NOISE
z
Check the accessory drive belt for damage and
correct installation. Check the accessory
mounting brackets and generator pulley for
looseness or misalignment.
z Is the accessory drive OK? Yes
GO to
G2 .
No
REPAIR as necessary. REFER to
Section 303 - 05 for diagnosis and testing
of the accessory drive system. TEST the
system for normal operation. G2 CHECK GENERATOR MOUNTING
z
Check the generator mounting for loose bolts
or misalignment.
z Is the generator mounted correctly? Yes
GO to
G3 .
No
REPAIR as necessary. TEST the system
for normal operation. G3 CHECK GENERATOR FOR ELECTRICAL Klj . 9 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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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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DESCRIPTION AND OPERATION
Battery and Cables
Vehicles are equipped with a 12 volt maintenance-
free battery that contains a built-in hydrometer. The
hydrometer eye indication is as follows:
zA green dot means the battery is OK.
z A yellow dot, red dot, or when the green dot is not visible, means the battery needs to be
charged.
WARNING: Batteries normally produce explosive gases which can cause personal injury.
Therefore, do not allow flames, sparks or lighted substances to come near the battery. When
charging or working near a battery, always shield your face and protect your eyes. Always
provide ventilation.
WARNING: When lifting a battery, excessive pressure on the end walls could cause acid
to leak out through the vent caps, resulting in personal injury, damage to the vehicle or the
battery.
WARNING: Keep out of the reach of children. Batteries contain sulfuric acid. Avoid
contact with skin, eyes, or clothing. Also, shield your eyes when working near the battery to
protect against possible splashing of the acid solution. In case of acid contact with skin or
eyes, flush immediately with water for a minimum of 15 minutes and get prompt medical
attention. If acid is swallowed, call a physician immediately.
Ford Motor Company strongly recommends that lead- acid batteries be returned to an authorized
recycling facility for disposal. SECTION 414-
01: Battery, Mounting and Cables 2003 Mustang Workshop Manual Klj . 1 ba
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