2003 FORD MUSTANG keyless

as detected by the door ajar circuit. For vehicles equipped with the remote keyless entry feature, any
signal the GEM detects when a valid remote transmitter button is depressed will reset both the
demand and courtesy lamp battery saver timers. This battery saver relay then restores power to both
the demand and courtesy lamp circuits.
Base Courtesy and Extended Lighting
The base courtesy lighting feature provides interior lighting for the convenience of the vehicle's
occupants. The courtesy lamps consist of the map/dome lamps for the coupe and the map lamps for
the convertible. All lamps designated as courtesy lamps will be illuminated whenever the GEM detects
that the driver or passenger doors become ajar, by means of the driver or passenger door ajar circuits.
The courtesy lamps will also be illuminated when the GEM detects that the dome lamp switch has
been activated, by means of the dome lamp switch circuit.
The extended courtesy lighting feature provides temporary extended illumination of the courtesy lamps
after the customer has entered the vehicle. The courtesy lamps will remain illuminated for 25 seconds
after the GEM detects that the driver and passenger doors are closed, as detected by the door ajar
circuits. The extended courtesy lighting feature will be terminated after the 25 second time-
out period,
or if the GEM detects that the ignition switch has been moved from the OFF position to either the RUN,
ACC, or START positions.
Demand Lighting
The GEM does not provide any special features to the demand lighting group with the exception of
providing a power source when the battery saver feature is active. The demand lighting group consists
of the luggage compartment lamp, the driver and passenger vanity mirror lamps, and the map lamps.
Illuminated Entry with Remote Keyless Entry
The illuminated entry with remote keyless entry feature, provides power to the courtesy lamps when
the remote transmitter is used. When the GEM detects that the ignition switch is in the OFF or key out
positions, and it detects that a valid remote transmitter unlock button has been depressed, power to
the courtesy lamps will be enabled. The courtesy lamp circuit will remain powered until one of the
following occurs:
zThe GEM detects that the ignition switch has been moved from the OFF, to the RUN, START,
or ACC position.
z The GEM detects any valid remote transmitter lock button is depressed.
z The courtesy lamp circuit has been powered for 25 seconds.
If the GEM detects any valid remote transmitter unlock button has been depressed, and the ignition
switch is in the OFF or key out position during the 25 second time- out, the courtesy lamp circuits will
remain powered for an additional 25 seconds.
Inspection and Verification
1. The interior lighting system is a generic electronic module (GEM) controlled system.
2. Verify the customer concern by operating the interior lighting system.
3. Visually inspect for the following obvious signs of mechanical and electrical damage. Klj . 2 ba
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DESCRIPTION AND OPERATION
Module Controlled Functions
The generic electronic module (GEM)(14B205) is the only multifunction control module on this vehicle.
The GEM controls the following functions:
zwarning chimes and warning lamps
z one- touch down window
z windshield washers and wipers
z battery saver
z illuminated entry with keyless remote entry
z interior lighting
SECTION 419-
10: Multifunction Electronic Control Modules 2003 Mustang Workshop Manual Klj . 1 ba
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DIAGNOSIS AND TESTING
Multifunction Electronic Module
For warning chime concerns, refer to
Section 413 - 09 .
For courtesy lamps/illuminated entry and battery saver concerns, refer to Section 417 - 02 .
For one- touch window concerns, refer to Section 501 - 11 .
For wiper/washer control and interval timer concerns, refer to Section 501 - 16 .
For keyless entry and power door lock concerns, refer to Section 501 - 14B .
For anti- theft concerns, refer to Section 419 - 01 .
SECTION 419-
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DESCRIPTION AND OPERATION
Keyless Entry
The electronic door lock system has two main components:
zgeneric electronic module (GEM)(14B204)
z keyless entry remote transmitter (15K601)
SECTION 501-
14B: Keyless Entry/Computer Operated Locks 2003 Mustang Workshop Manual Klj . 1 ba
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DIAGNOSIS AND TESTING
Keyless Entry
Refer to Wiring Diagrams Cell
59 , Generic Electronic Module for schematic and connector
information.
Refer to Wiring Diagrams Cell 111 , Remote Keyless Entry (RKE) for schematic and connector
information.
Principles of Operation
NOTE: Battery power and ground must be remove before disconnecting the GEM connectors to avoid
setting false codes.
Power Locks Operation
The power locks feature allows the customer to lock and unlock the doors via momentary switches
located on the driver and passenger door. When the GEM detects a momentary press of the driver or
passenger lock button, the GEM will supply power to the driver or passenger lock actuators for
approximately 250 ms from relays internal to the GEM. When the GEM detects a momentary press of
the driver or passenger unlock button, the GEM will supply power to the driver or passenger unlock
actuators for approximately 250 ms from relays internal to the GEM.
Remote Keyless Entry Door Locks Operation
The remote entry feature allows the customer to unlock the driver door, unlock all doors, and lock all
doors using a valid remote transmitter as long as the ignition switch is not in RUN or START. The
driver door is unlocked whenever the GEM detects a valid remote transmitter unlock transmission. All
the doors are unlocked when the GEM detects a second valid remote transmitter unlock transmission
within three seconds of the first transmission. All the doors are locked when the GEM detects a valid
remote transmitter lock transmission. If the GEM detects a second valid remote transmitter lock
transmission within three seconds of the first transmission, the doors will lock again, the horn will
sound for 20 ms and the parking lamps will flash for 200 ms to indicate the doors are locked. If the
GEM detects the driver or passenger door is ajar during the second lock transmission, the doors are
locked again and the horn is sounded twice. If the GEM detects a valid remote transmitter lock
transmission within three seconds of detecting a valid remote transmitter unlock transmission, the SECTION 501-
14B: Keyless Entry/Computer Operated Locks 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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GEM will lock all the doors.
Remote Keyless Entry Luggage Compartment Operation
The luggage compartment lid is released whenever the GEM detects a valid remote transmitter
luggage compartment release transmission.
Panic Alarm Operation
The panic alarm feature allows the vehicle to initiate an alarm for 2.75 minutes to identify itself using a
valid remote transmitter. The panic alarm is activated whenever the GEM detects the ignition switch is
in the OFF position or if the key is removed from the ignition, and the GEM detects a valid PANIC
response from the remote transmitter. When the panic alarm is activated, the GEM:
zilluminates the courtesy lamps.
z flashes the parking lamps.
z toggles the horn on and off.
The panic alarm is deactivated whenever GEM detects:
zif the key causes a transition of the ignition switch circuits to
„ACC.
„ RUN.
„ START.
z the remote transmitter
„panic button.
„ unlock button.
The panic alarm is also deactivated after 2.75 minutes have gone by.
Remote Transmitter Programming Operation
This feature allows the customer to program up to four different transmitter identification codes (TIC)
for four remote transmitters to the vehicle at any time. For additional information, refer to
Programming — Keyless Entry Remote Transmitter .
Inspection and Verification 1. The keyless entry system is a generic electronic module (GEM).
2. Verify the customer concern by using the remote transmitters to operate the keyless entry system.
3. Visually inspect for the following obvious signs of mechanical and electrical damage.
Visual Inspection Chart Klj . 2 ba
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PINPOINT TEST D: THE LUGGAGE COMPARTMENT DOOR IS
INOPERATIVE USING THE REMOTE TRANSMITTER the normal scan tool PID list. It can be
located in the Function Test —
"
Transmitter Tic/DATA". When this test is
activated, the appropriate results may be
obtained when pressing the keyfob
buttons.
z Remove the ignition key from the ignition.
z Connect the diagnostic tool.
z Monitor the GEM FUNCTION TEST
TIC/DATA while pressing the lock and
unlock buttons on the remote transmitter.
z Does LAST DATA RECEIVED match
the button presses of the remote
transmitter? INSTALL a new GEM. For additional
information, REFER to
Section 419 - 10 .
REPEAT the self- test. CLEAR the DTCs.
No
GO to C4 .
C4 CHECK THE BATTERIES IN THE
REMOTE TRANSMITTER z
Install new batteries in the remote
transmitter.
z Connect the diagnostic tool.
z Monitor the GEM FUNCTION TEST
TIC/DATA while pressing the lock and
unlock buttons on the remote transmitter.
z Does LAST DATA RECEIVED match
the button presses of the remote
transmitter? Yes
SYSTEM is OK. REPEAT the self-test.
CLEAR the DTCs.
No
GO to
C5 .
C5 REPROGRAM THE REMOTE
TRANSMITTERS TO THE GEM z
NOTE: When carrying out the following
procedure it must be noted that all
previous programmed remote transmitters
will be erased. The customer needs to be
informed that any remote transmitters not
present during the programming mode will
not operate the vehicle. All remote
transmitters must be programmed at the
same time.
z Reprogram the remote transmitter to the
GEM. For additional information, refer to
Programming — Keyless Entry Remote
Transmitter .
z Connect the diagnostic tool.
z Monitor the GEM FUNCTION TEST
TIC/DATA while pressing the lock and
unlock buttons on the remote transmitter.
z Does LAST DATA RECEIVED match
the button presses of the remote
transmitter? Yes
SYSTEM is OK. REPEAT the self-test.
CLEAR the DTCs.
No
PROGRAM a new remote transmitter to the
vehicle. For additional information, REFER to
Programming
— Keyless Entry Remote
Transmitter . REPEAT the self-
test. CLEAR
the DTCs. If the problem still remains,
INSTALL a new GEM and program the remote
transmitters to the vehicle. For additional
information, REFER to Section 419 - 10 .
REPEAT the self- test. CLEAR the DTCs. Test Step Result / Action to Take
D1 CHECK IGNITION STATES
z
Connect the diagnostic tool.
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. Yes
GO to
D2 .
No Klj . 14 ba
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z
Do the PID values agree with the ignition switch
positions? REFER to
Section 413 - 09 for
key- in-ignition warning chime
concerns. D2 CHECK THE GEM PID LAST DATA RECEIVED FOR
LUGGAGE COMPARTMENT z
Remove the ignition key from the ignition.
z Connect the diagnostic tool.
z Monitor the GEM PID LAST DATA RECEIVED while
pressing and releasing the luggage compartment, panic,
lock, and unlock buttons of the remote transmitter.
z Does LAST DATA RECEIVED match the button
presses of the remote transmitter? Yes
GO to
D5 .
No
GO to D3 .
D3 CHECK THE BATTERIES IN THE REMOTE
TRANSMITTER z
Install new batteries in the remote transmitter.
z Connect the diagnostic tool.
z Monitor the GEM FUNCTION TEST TIC/DATA while
pressing the luggage compartment button on the remote
transmitter.
z Does LAST DATA RECEIVED match the button
presses of the remote transmitter? Yes
SYSTEM is OK. REPEAT the
self-
test. CLEAR the DTCs.
No
GO to D4 .
D4 REPROGRAM THE REMOTE TRANSMITTERS TO THE
GEM z
NOTE: When carrying out the following procedure, it
must be noted that all previous programmed remote
transmitters will be erased. The customer needs to be
informed that any remote transmitters not present during
the programming mode will not operate the vehicle. All
remote transmitters must be programmed at the same
time.
z Reprogram the remote transmitter to the GEM. For
additional information, refer to Programming — Keyless
Entry Remote Transmitter .
z Connect the diagnostic tool.
z Monitor the GEM FUNCTION TEST TIC/DATA while
pressing the lock and unlock buttons on the remote
transmitter.
z Does LAST DATA RECEIVED match the button
presses of the remote transmitter? Yes
SYSTEM is OK. REPEAT the
self-
test. CLEAR the DTCs.
No
PROGRAM a new remote
transmitter to the vehicle. For
additional information, REFER
to Programming — Keyless
Entry Remote Transmitter .
REPEAT the self- test. CLEAR
the DTCs. If the problem still
remains, INSTALL a new GEM
and program the remote
transmitters to the vehicle. For
additional information, REFER
to Section 419 - 10 . REPEAT
the self- test. CLEAR the
DTCs. D5 CHECK THE GEM OUTPUT TO THE LUGGAGE
COMPARTMENT z
Trigger the GEM active command RELEASE to ON and
OFF.
z Did the luggage compartment release? Yes
INSTALL a new GEM. For
additional information, REFER
to
Section 419 - 10 . REPEAT
the self- test. CLEAR the
DTCs.
No
GO to D6 .
D6 CHECK CIRCUIT 931 (OG) FOR OPEN
z
Disconnect: Luggage Compartment Lid Release Relay.
z Measure the voltage between luggage compartment lid
release relay Pin 2, Circuit 931 (OG), harness side and
ground; and between luggage compartment lid release Yes
GO to
D7 .
No Klj . 15 ba
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