fuse FORD MUSTANG 2003 Repair Manual

z
Measure the resistance between GEM C201e pin 22, circuit
1002 (BK/PK), harness side and CJB Fuse 32 (15A), pin 2,
circuit 1002 (BK/PK), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
B8 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. B8 CHECK GEM INPUT CIRCUIT FOR OPEN —
KEY-IN-
IGNITION SWITCH CIRCUIT 158 (BK/PK) z
Measure the resistance between GEM C201e pin 9, circuit
158 (BK/PK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
GO to
B9 .
No
REPAIR circuit 158
(BK/PK) and key-in-
ignition switch for failure.
REFER to Switch — Key -
In - Ignition Warning .
REPEAT the self- test.
CLEAR the DTCs. B9 CHECK GEM VOLTAGE INPUT CIRCUITS FOR SHORT TO
POWER — IGNITION SWITCH CIRCUITS 911 (WH/LG), AND 1002
(BK/PK) z
Key in OFF position.
z Disconnect: CJB Fuse 28 (15A).
z Disconnect: CJB Fuse 32 (15A).
z Disconnect: GEM C201e.
z Remove the ignition key. Measure the voltage between GEM
C201e pin 8, circuit 911 (WH/LG), harness side and ground,
and between GEM C201e pin 22, circuit 1002 (BK/PK),
harness side and ground.
z Are the voltages greater than 10 volts? Yes
REPAIR the circuit in
question. REPEAT the
self-
test. CLEAR the
DTCs.
No
GO to B10 .
B10 CHECK GEM INPUT CIRCUIT FOR SHORT TO GROUND
—-
KEY- IN-IGNITION SWITCH CIRCUIT 158 (BK/PK) z
Disconnect: GEM C201e.
z Remove the ignition key. Measure the resistance between
GEM C201e pin 9, circuit 158 (BK/PK), harness side and Yes
GO to
B11 . Klj . 8 ba
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z
Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID P_DR_SW while opening and closing
the passenger door.
z Do the GEM PID P_DR_SW values indicate CLOSED and
AJAR correctly? Yes
GO to
D17 .
No
GO to D11 .
D5 CHECK CIRCUIT 765 (YE/BK) AND DRIVER DOOR AJAR
SWITCH FOR OPEN OR SHORT TO GROUND z
Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_DR_SW while opening and closing
the driver door.
z Does the GEM PID D_DR_SW value indicate AJAR with
driver door closed? Yes
GO to
D6 .
No
GO to D8 .
D6 ISOLATE SHORT TO GROUND ON CIRCUIT 765 (YE/BK)
z
Disconnect: Driver Door Ajar Switch C526.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_DR_SW.
z Does GEM PID D_DR_SW read CLOSED? Yes
INSTALL a new driver door
ajar switch. REFER to
Section 501
- 14A . REPEAT
the self- test. CLEAR the
DTCs.
No
GO to D7 .
D7 CHECK CIRCUIT 765 (YE/BK) FOR SHORT TO GROUND
BETWEEN GEM AND DRIVER DOOR AJAR SWITCH z
Disconnect: GEM C201c.
z Measure the resistance between GEM C201c pin 13, circuit
765 (YE/BK), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
D17 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. D8 CHECK CIRCUIT 765 (YE/BK) FOR OPEN
z
Disconnect: Driver Door Ajar Switch C526.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Connect a 10A fused jumper wire between driver door ajar
switch C526 pin 2, circuit 765 (YE/BK), harness side and
ground while monitoring GEM PID D_DOOR. Yes
GO to
D10 .
No
GO to D9 . Klj . 12 ba
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z
Disconnect: Passenger Door Ajar Switch C602.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID P_DR_SW.
z Does GEM PID P_DR_SW read CLOSED? Yes
INSTALL a new passenger
door ajar switch. REFER to
Section 501
- 14A . REPEAT
the self- test. CLEAR the
DTCs.
No
GO to D13 .
D13 CHECK CIRCUIT 761 (GN/RD) FOR SHORT TO GROUND
BETWEEN GEM AND PASSENGER DOOR AJAR SWITCH z
Disconnect: GEM C201c.
z Measure the resistance between GEM C201c pin 5, circuit
761 (GN/RD), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
D17 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. D14 ISOLATE OPEN CIRCUIT 761 (GN/RD)
z
Disconnect: Passenger Door Ajar Switch C602.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Connect a 10A fused jumper wire between the passenger
door ajar switch C602 pin 2, circuit 761 (GN/RD), harness
side and ground while monitoring the GEM PID P_DR_SW.
z Does GEM PID P_DR_SW read AJAR with jumper wire
installed? Yes
GO to
D16 .
No
GO to D15 .
D15 CHECK FOR OPEN ON CIRCUIT 761 (GN/RD) BETWEEN
GEM AND PASSENGER DOOR AJAR SWITCH z
Disconnect: GEM C201c.
z Measure the resistance between GEM C201c pin 5, circuit
761 (GN/RD), harness side and passenger door ajar switch
C602 pin 2, circuit 761 (GN/RD), harness side. Yes
GO to
D17 .
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. Klj . 14 ba
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z
Is the resistance greater than 10,000 ohms? F8 ISOLATE OPEN ON CIRCUIT 85 (BN/LB)
z
Disconnect: Safety Belt Switch C323.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Connect a 10A fused jumper wire between safety belt
switch C323 pin 2, circuit 85 (BN/LB), harness side and
ground while monitoring GEM PID D_SBELT.
z Does GEM PID GEM PID D_SBELT read OUT with
jumper wire installed? Yes
GO to
F10 .
No
GO to F9 .
F9 CHECK CIRCUIT 85 (BN/LB) FOR OPEN BETWEEN GEM
AND SEATBELT SWITCH z
Disconnect: Safety Belt Switch C323.
z Disconnect: GEM C201b.
z Measure the resistance between GEM C201b pin 8, circuit
85 (BN/LB), harness side and safety belt switch C323 pin 2,
circuit 85 (BN/LB), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
F11 .
No
REPAIR the circuit. CLEAR
the DTCs. TEST the system
for normal operation. F10 CHECK CIRCUIT 1205 (BK) FOR AN OPEN CIRCUIT
BETWEEN SAFETY BELT SWITCH AND GROUND z
Disconnect: Safety Belt Switch C323.
z Measure the resistance between the safety belt switch
C323 pin 1, circuit 1205 (BK), harness side and ground. Yes
INSTALL a new safety belt
switch. REPEAT the self-
test. CLEAR the DTCs. Klj . 19 ba
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provide ventilation.
WARNING: When lifting a plastic- cased battery, excessive pressure on the end walls
could cause acid to spew through the vent caps resulting in personal injury, damage to the
vehicle or to the battery. Lift with a battery carrier or with your hands on opposite corners.
1. Verify the customer concern by operating the engine to duplicate the concern.
2. Inspect the charging system (battery, generator cable, harness connectors, connections) to determine if any obvious mechanical or electrical concerns exist. If found, repair as necessary
and test the system for normal operation. Refer to the following tables:
3. Check the operation of the charging system warning indicator lamp (instrument cluster). Normal operation is as follows:
zWith the ignition switch OFF, the charging system warning indicator should be OFF.
z With the ignition switch in RUN and the engine off, the charging system warning indicator
light should be on.
z With the engine running, the charging system warning indicator light should be off.
4. Verify the battery is being charged. Carry out the Battery— Load Test. Refer to Component
Tests in this section.
5. If the customer concern is verified after the initial inspection, refer to the Symptom Chart to determine which tests to carry out.
Symptom Chart Visual Inspection Chart
Mechanical Electrical
z
Battery case, posts, hold- down clamp, cables and
connections
z Generator drive (serpentine) belt for condition and
tension. Refer to Section 303 - 05 .
z Generator pulley z
Battery junction box (BJB)
fuse 20 (20A)
z Fuse links
z Circuitry
z Battery charge warning
indicator
z Cables
Normal Charging System Voltages Ignition
Switch
Position A Circuit
36
(YE/WH) I Circuit
904
(LG/RD) Generator B+
Circuit 38 (BK/OG) Battery Engine to
battery
ground Charging
System Warning Indicator
Operation OFF 12V 0V 12V 12V 0V Off
RUN-
engine off 12V 1-
3V 12V 12V 0V Illuminated
RUN-
engine
running 13-
15V 13-
15V 13-
15V 13-15V 0V Off Klj . 3 ba
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Pinpoint Tests
CAUTION: Do not make jumper connections except as directed. Incorrect connections
may damage the voltage regulator test terminals, fuses, or fuse links.
CAUTION: Do not allow any metal object to come in contact with the generator housing
and internal diode cooling fins.
NOTE: All voltage measurements are referenced to the negative (- ) battery post unless otherwise
specified. PINPOINT TEST A: BATTERY IS DISCHARGED OR VOLTAGE IS Symptom Chart
Condition
Possible Sources Action
z Battery is discharged or voltage is
low z
Circuitry.
z High key- off current
drain(s).
z Battery.
z Generator. z
Go To Pinpoint
Test A .
z The charging system warning
indicator is on with the engine
running (the system voltage does
not increase) z
Circuitry.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test B .
z The system overcharges (the
battery voltage is greater than 15.5
volts) z
Circuitry.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test C .
z The charging system warning
indicator is on with the engine
running and the battery increases
voltage z
Circuitry.
z Instrument cluster.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test D .
z The charging system warning
indicator is off with the ignition
switch in the RUN position and the
engine off z
Bulb.
z Circuitry.
z Instrument cluster.
z Voltage regulator.
z Generator. z
Go To Pinpoint
Test E .
z The charging system warning
indicator flickers or is intermittent z
Central junction box
(CJB) fuse 5 (15A).
z Generator
connector
unplugged (C102a).
z Circuitry.
z Generator. z
Go To Pinpoint
Test F .
z The generator is noisy zBolts or brackets.
z Drive belt.
z Generator or pulley. z
Go To Pinpoint
Test G .
z Radio interference zGenerator.
z Circuitry.
z In-vehicle
entertainment
system. z
Go To Pinpoint
Test F . Klj . 4 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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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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