key battery FORD MUSTANG 2003 Owner's Guide

z
Is the voltage equal to battery positive voltage (B+)? B2 CHECK GENERATOR A CIRCUIT 36 (YE/WH)
z
Disconnect: Generator C102c (4.6L 4V) or C102a (3.8L or 4.6L
2V).
z Measure the voltage between the generator C102c (4.6L 4V) or
C102a (3.8L or 4.6L 2V) pin 3, circuit 36 (YE/WH), harness side
and ground.
z Is the voltage equal to battery positive voltage (B+)? Yes
GO to
B3 .
No
REPAIR the circuit.
TEST the system for
normal operation. B3 CHECK I CIRCUIT 904 (LG/RD) FOR AN OPEN
z
Key in ON position.
z With the ignition switch in the RUN position and the engine off,
measure the voltage 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 Is the voltage equal to battery positive voltage (B+)? Yes
GO to
B4 .
No
REPAIR the circuit.
TEST the system for
normal operation. B4 CHECK FOR VOLTAGE DROP IN B+ CIRCUIT 38 (YE/WH)
z
Key in START position.
z With the engine at 2,000 rpm, measure the voltage drop between
the generator C102b, circuit 38 (BK/OG), component side and
positive battery terminal. Yes
INSTALL a new
generator. REFER to
Section 414
- 02 .
TEST the system for
normal operation.
No Klj . 6 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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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 N: THE PARKING, REAR OR LICENSE LAMPS ARE
ON CONTINUOUSLY
Test Step Result / Action to Take
N1 CHECK THE HEADLAMP
SWITCH z
Key in OFF position.
z Disconnect: Headlamp
Switch C205.
z Key in ON position.
z Are the parking, rear or
licences lamps on? Yes
REPAIR Circuit 14 (BN) for a short to battery. TEST the
system for normal operation.
No
INSTALL a new headlamp switch; REFER to
Lamp Switch — Headlamp . TEST the system for normal operation. Klj . 3 ba
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PINPOINT TEST T: THE REVERSING LAMPS ARE ON
CONTINUOUSLY z
Is the resistance less than 5 ohms? No
REPAIR the circuit.
TEST the system for
normal operation.
Test Step Result / Action to Take
T1 CHECK THE CONTINUITY OF THE
DTR SENSOR (A/T) OR THE
REVERSING LAMP SWITCH (M/T) z
Key in OFF position.
z Disconnect: DTR Sensor C167
(A/T).
z Disconnect: Reversing Lamp Switch
C169 (M/T).
z Set the parking brake.
z Key in ON position.
z Select REVERSE.
z Are the reversing lamps
illuminated? Yes
REPAIR Circuit 140 (BK/PK) for short to battery.
TEST the system for normal operation.
No
INSTALL a new DTR sensor (A/T) or reversing lamp
switch (M/T); REFER to
Section 307 - 01 ,
Section 308 - 03A , or
Section 308 - 03B . TEST the system for
normal operation. Klj . 4 ba
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DIAGNOSIS AND TESTING
Interior Lighting
Refer to Wiring Diagrams Cell
111 , Remote Control Alarm and Lock System for schematic and
connector information.
Refer to Wiring Diagrams Cell 59 , Generic Electronic Module for schematic and connector
information.
Refer to Wiring Diagrams Cell 89 , Courtesy Lamps for schematic and connector information.
Principles of Operation
Battery Saver
The battery saver feature provides automatic shut- off of power to demand and courtesy lamp circuitry.
When the generic electronic module (GEM) detects the ignition switch circuits are in the key OFF or
removed ignition key positions, power will be disabled after individual time- out periods of 30 minutes
for the demand lamps, and 10 minutes for the courtesy lamps. However, the time- out period for the
courtesy lamps changes to 30 minutes when the GEM detects that the luggage compartment lid is ajar
by means of the luggage compartment lid ajar circuit, or if the dome lamp is switched on by means of
the dome lamp circuit. When the GEM detects that the ignition switch is in the RUN, ACC, or START
positions, the battery saver feature is disabled.
The battery saver timer for the demand lamps is reset when the GEM detects that the ignition switch is
in the OFF or key out positions or when the GEM detects any one of the following conditions:
zthe driver or passenger door becomes ajar, as detected by the door ajar circuit
z the luggage compartment lid becomes ajar, as detected by the luggage compartment lid ajar
circuit
z the dome lamp switch is activated, as detected by the dome lamp switch circuit
The battery saver timer for the courtesy lamps is reset when the GEM detects that the ignition switch is
in the OFF or key out positions or when the GEM detects the driver or passenger door becomes ajar SECTION 417-
02: Interior Lighting 2003 Mustang Workshop Manual Special Tool(s)
73 Digital Multimeter or
equivalent
105-
R0051 Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool Klj . 1 ba
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