2003 FORD MUSTANG test G

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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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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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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