2003 FORD MUSTANG key

E2 CHECK IGNITION STATES
z
Connect the diagnostic tool.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PIDS IGN_KEY, IGN_A, IGN_S, and
IGN_R while cycling the ignition switch through the OFF,
ACC, RUN, START and key out positions.
z Do the PID values agree with the ignition switch
states? Yes
GO to
E3 .
No
Go To Pinpoint Test B .
E3 CHECK GEM INTERNAL TONE OPERATION
z
Enter the following diagnostic mode on the diagnostic tool:
GEM Active Command.
z Trigger the GEM active command CHIME ON and OFF.
z Does the chime operate correctly? Yes
GO to
E4 .
No
GO to E9 .
E4 CHECK GEM INPUT FROM DOOR AJAR CIRCUIT
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 Do the GEM PID D_DR_SW values indicate CLOSED
and AJAR correctly? Yes
GO to
E5 .
No
GO to Pinpoint Test D .
E5 MONITOR EXTERIOR LAMP INPUT FOR CORRECT
STATE z
Key in OFF position.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID PARK_SW, while triggering the
headlamp switch ON and OFF.
z Do the GEM PID PARK_SW values indicate ON and
OFF correctly? Yes
GO to
E9 .
No
GO to E6 .
E6 CHECK EXTERIOR LAMP INPUT CIRCUIT FOR SHORT
TO POWER — GEM PID PARK_SW z
Key in OFF position.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID PARK_SW, while opening and
closing the driver door.
z Does the GEM PID PARK_SW value always indicate
ON? Yes
GO to
E8 .
No
GO to E7 .
E7 CHECK CIRCUIT 14 (BN) FOR OPEN
z
Key in OFF position.
z Disconnect: GEM C201c.
z Disconnect: Headlamp Switch C205.
z Measure the resistance between GEM C201c pin 7, circuit
14 (BN), harness side and headlamp switch C205 pin R,
circuit 14 (BN), harness side. Yes
GO to
E9 .
No
REPAIR the circuit. REPEAT
the self- test. CLEAR the
DTCs. Klj . 16 ba
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PINPOINT TEST F: THE SAFETY BELT WARNING CHIME DOES NOT
OPERATE CORRECTLY z
Is the resistance less than 5 ohms? E8 TEST CIRCUIT 14 (BN) FOR SHORT TO BATTERY
z
Key in OFF position.
z Disconnect: GEM C201c.
z Set the headlamp switch in the OFF position. Measure the
voltage between GEM C201c pin 7, circuit 14 (BN),
harness side and ground.
z Is the voltage greater than 10 volts? Yes
REPAIR the circuit. REPEAT
the self-
test. CLEAR the
DTCs.
No
GO to E9 .
E9 CHECK FOR CORRECT MODULE OPERATION
z
Check:
zfor corrosion
z for pushed- out pins
z connector seated correctly
z Connect any disconnected connectors.
z Make sure all other system connectors are fully seated.
z Operate the system and verify the concern is still present.
z Is the concern still present? Yes
INSTALL a new GEM.
REFER to
Section 419 - 10 .
CLEAR the DTCs. REPEAT
the GEM self- test.
No
The system is operating
correctly at this time.
Concern may have been
caused by a loose or
corroded connector. CLEAR
the DTCs. REPEAT the self-
test. Test Step Result / Action to Take
F1 CHECK IGNITION STATES
NOTE:
Verify the belt minder is activated before
diagnosing.
z Connect the diagnostic tool.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID. Yes
GO to
F2 .
No
Go To Pinpoint Test B . Klj . 17 ba
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z
Monitor the GEM PIDS IGN_KEY, IGN_A, IGN_S, and
IGN_R while cycling the ignition switch through the OFF,
ACC, RUN, START and key out positions.
z Do the PID values agree with the ignition switch
states? F2 DETERMINE IF THE GEM IS RECEIVING CORRECT
SAFETY BELT SWITCH STATUS z
Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_SBELT while buckling and
unbuckling the driver safety belt.
z Does the GEM PID D_SBELT read OUT and IN
correctly? Yes
GO to
F3 .
No
GO to F5 .
F3 CHECK THE GEM INTERNAL TONE OPERATION
z
Enter the following diagnostic mode on the diagnostic tool:
GEM Active Command.
z Trigger the GEM active command CHIME ON and OFF.
z Does the chime operate correctly? Yes
GO to
F4 .
No
GO to F11 .
F4 CHECK THE SAFETY BELT WARNING LAMP OPERATION
z
Cycle the ignition switch from OFF to RUN while monitoring
the instrument cluster safety belt indicator lamp.
z Does instrument cluster safety belt indicator lamp
illuminate for approximately three seconds? Yes
GO to
F11 .
No
REFER to Section 413 - 01 .
F5 DETERMINE IF CIRCUIT 85 (BN/LB) IS OPEN OR
SHORTED TO GROUND z
Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_SBELT, while buckling and
unbuckling the driver safety belt.
z Does the GEM PID D_SBELT value indicate OUT with
the driver safety belt buckled? Yes
GO to
F6 .
No
GO to F8 .
F6 ISOLATE THE SHORT TO GROUND ON CIRCUIT 85
(BN/LB) z
Disconnect: Safety Belt Switch C323.
z Enter the following diagnostic mode on the diagnostic tool:
GEM PID.
z Monitor the GEM PID D_SBELT.
z Does the GEM PID D_SBELT value indicate IN? Yes
INSTALL a new safety belt
switch. REPEAT the self-
test. CLEAR the DTCs.
No
GO to
F7 .
F7 CHECK CIRCUIT 85 (BN/LB) FOR A SHORT TO GROUND
BETWEEN GEM AND SAFETY BELT SWITCH z
Disconnect: GEM C201d.
z Measure the resistance between GEM C201d pin 8, circuit
85 (BN/LB), harness side and ground. Yes
GO to
F11 .
No
REPAIR the circuit. REPEAT
the self- test. CLEAR the
DTCs. Klj . 18 ba
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REMOVAL AND INSTALLATION
Switch —
Key-In-Ignition Warning
Removal 1. Remove the ignition switch lock cylinder. 1. Insert the ignition key and turn to the RUN position.
2. Insert a punch in the access hole of the steering column and press the release tab while pulling out the ignition switch lock cylinder.
2. Remove the key- in-ignition warning switch.
1. Release the clip.
2. Push the key- in-ignition warning switch off the rear of the ignition switch lock cylinder.
Installation 1. To install, reverse the removal procedure. zVerify ignition switch lock cylinder operation.
SECTION 413-
09: Warning Devices 2003 Mustang Workshop Manual Klj . 1 ba
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DESCRIPTION AND OPERATION
Charging System
The charging system is a negative ground system consisting of the following:
zgenerator
z internal voltage regulator
z charging system warning indicator
z storage battery
z necessary wiring and cables
The generator is belt- driven by the engine accessory drive system.
With the ignition key in the run position, voltage is applied through the warning indicator I circuit to the
voltage regulator. This turns the regulator on, allowing current to flow from battery sense A circuit to
the generator field coil. When the engine is started, the generator begins to generate alternating
current (AC) which is converted to direct current (DC) internally. This current is then supplied to the
vehicle's electrical system through the output terminal (B+) of the generator.
Once the generator begins generating current, a voltage signal is taken from the generator stator and
fed back to the internal regulator. This voltage feedback signal (typically half the battery voltage) is
used to turn off the warning indicator.
With the system functioning normally, the generator output current is determined by the voltage of the
A circuit. This A circuit voltage (battery sense circuit) is compared to a set voltage internal to the
regulator, and the regulator controls the generator field current to maintain the correct generator
output.
The set voltage will vary with temperature and is typically higher in cold temperatures than in warm
temperatures. This allows for better battery recharge in the winter and reduces the chance of
overcharging in the summer.
The battery is a 12 volt direct current source connected in a negative ground system. The battery case
is sealed and includes two vent holes to release gases. The battery has three major functions:
zengine cranking power source
z voltage stabilizer for the electrical system
z temporary power when electrical loads exceed the generator output current
Circuit Description
Battery Output Terminal (B+)
The generator output is supplied through the battery positive output (B+) terminal on the back of the
generator to the battery and electrical system.
I Circuit 904 (LG/RD)
The I (ignition) circuit is used to turn on the voltage regulator. This circuit is powered up with the
ignition key in the run position. This circuit is also used to turn the charging system warning indicator
on if there is a fault in the charging system operation. SECTION 414-
00: Charging System — General Information 2003 Mustang Workshop Manual Klj . 1 ba
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Functionality
With the ignition switch in the RUN position, voltage is applied through the warning indicator I circuit
904 (LG/RD) to the voltage regulator. This turns the regulator on, allowing current to flow from battery
sense A circuit 36 (YE/WH) to the generator field coil. When the engine is started, the generator
begins to generate alternating current (AC) which is internally converted to direct current (DC). This
current is then supplied to the vehicle's electrical system through the output (B+) terminal of the
generator.
Once the generator begins generating current, a voltage signal is taken from the generator stator and
fed back to the regulator internally. This voltage feedback signal (typically half the battery voltage) is
used to turn off the warning indicator.
With the system functioning normally, the generator output current is determined by the voltage of the
A circuit. The A circuit voltage is compared to a set voltage internal to the regulator, and the regulator
controls the generator field current to maintain the correct generator output.
The set voltage will vary with temperature and is typically higher in cold temperatures and lower in
warm temperatures. This allows for better battery recharge in the winter and reduces the chance of
overcharging in the summer.
Battery Positive Output Circuit 38 (B+) (BK/OG)
The generator output is supplied through the battery positive output (B+) terminal on the back of the
generator to the battery and electrical system.
I Circuit 904 (LG/RD)
The I (ignition) circuit is used to turn on the voltage regulator. This circuit is powered up with the
ignition key in the run position. This circuit is also used to turn the charging system warning indicator
on if there is a fault in the charging system operation.
A Circuit 36 (YE/WH)
The A circuit or battery sense circuit is used to sense battery voltage. This voltage is used by the
regulator to determine generator output. This circuit is used to supply current to the generator field
(rotor). The amount of current supplied to the rotor will determine generator output.
Inspection and Verification
WARNING: Batteries contain sulfuric acid. Avoid contact with skin, eyes, or clothing.
Also, shield your eyes when working near batteries 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.
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 Connector C102a End View
A Circuit 36 (YE/WH)
I Circuit 904 (LG/RD) Klj . 2 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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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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