2003 FORD MUSTANG light

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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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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Symptom Chart
Pinpoint Tests
CAUTION: Before removing and installing the GEM or its connectors, disconnect the Output Circuit Failure
B2488 RF Side Repeater Lamp
Output Circuit Failure GEM REFER to
Section 417 - 01 .
C1189 Brake Fluid Level Sensor
Input Short Circuit to Ground GEM REFER to
Section 413 - 01 .
C1223 Lamp Brake Warning
Output Circuit Failure GEM REFER to
Section 413 - 01 .
C1225 Lamp Brake Warning
Output Circuit Short to
Battery GEM REFER to
Section 413 - 01 .
Symptom Chart Condition
Possible Sources Action
z No communication with the generic
electronic module z
CJB Fuse 39
(5A)
z GEM.
z Circuitry. z
GO to
Pinpoint Test A .
z The courtesy lamps are inoperative zCJB Fuse 7
(20A).
z Door ajar switch
(es).
z Courtesy lamp
assemblies.
z Circuitry.
z GEM.
z Ignition Switch.
z Headlamp
Switch. z
GO to
Pinpoint Test B .
z The demand lighting is inoperative zCJB Fuse 7
(20A).
z Circuitry.
z GEM.
z Door ajar switch
(es).
z Demand lamp
assemblies.
z Ignition Switch.
z Headlamp
Switch. z
GO to
Pinpoint Test C .
z The illuminated entry is inoperative
when using the remote transmitter z
Remote
transmitter.
z GEM. z
GO to
Pinpoint Test D .
z The battery saver does not
deactivate after timeout z
Circuitry.
z GEM. z
GO to
Pinpoint Test E . Klj . 5 ba
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PINPOINT TEST C: THE DEMAND LIGHTING IS INOPERATIVE z
Is the resistance less than 5 ohms? CLEAR the DTCs.
B21 CHECK GROUND CIRCUIT 1205 (BK) FOR OPEN
z
Measure the resistance between luggage compartment lid
switch C430 Pin 1, Circuit 1205 (BK), harness side and
ground.
z Is the resistance less than 5 ohms? Yes
INSTALL a new luggage
compartment solenoid.
For additional information,
REFER to
Section 501 -
14A . REPEAT the self-
test. CLEAR the DTCs.
No
REPAIR the circuit.
REPEAT the self- test.
CLEAR the DTCs. Test Step Result / Action to Take
C1 CHECK GEM SUPPLIED POWER TO THE DEMAND LAMPS
z
Turn on both map lamps by depressing the map lamp
switches.
z Turn on both vanity mirror lamps.
z Open the luggage compartment lid.
z Do any of the lamps illuminate? Yes
GO to
C8 .
No
GO to C2 .
C2 CHECK IGNITION STATES
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
positions? Yes
GO to
C3 .
No
For key- in-ignition
concerns, REFER to
Section 413 - 09 .
C3 CHECK DRIVER AND PASSENGER DOOR AJAR INPUTS TO
THE GEM z
Monitor the GEM PIDs D_DOOR and P_DOOR, while
opening and closing the driver and passenger doors.
z Did the GEM PIDs D_DOOR and P_DOOR agree with the
driver and passenger door positions? Yes
GO to
C4 .
No
REFER to Section 413 -
09 . Klj . 12 ba
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REMOVAL AND INSTALLATION
Lamp Assembly —
Map/Dome
Removal 1. Disconnect the battery ground cable.
2. Remove the lamp lens from the lamp assembly.
3. Remove the lamp assembly. 1. Remove the screws.
2. Remove the lamp assembly.
z Disconnect the electrical connectors.
Installation 1. NOTE: When the battery is disconnected and reconnected, some abnormal drive symptoms
may occur while the vehicle relearns its adaptive strategy. The vehicle may need to be driven
16 km (10 mi) or more to relearn the strategy.
To install, reverse the removal procedure.
SECTION 417-
02: Interior Lighting 2003 Mustang Workshop Manual Klj . 1 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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DESCRIPTION AND OPERATION
Body
Body and Sheet Metal
The body:
zIs a unibody open cowl structure.
z Is constructed of a lightweight, all- steel material with removable bolted hood (16612), front
fenders (16005), doors, and luggage compartment lid.
SECTION 501-
00: Body System — General Information 2003 Mustang Workshop Manual Klj . 1 ba
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DIAGNOSIS AND TESTING
Body System
Inspection and Verification
Leaks
NOTE:
Trim will reveal the location of most leaks.
1. Remove any trim or carpet in the general area of the leak.
2. Road test or water test the vehicle.
3. Inspect for a dust pattern around the area in question. Inspect for water paths near and above the area in question.
4. Some leaks can be located by placing bright light under the vehicle, removing any necessary trim or carpet, and inspecting the interior of the body at joints and weld lines.
Noise
Wind noise, rattles, and their sources are detected by driving the vehicle at highway speeds. The
vehicle should be driven in four different directions with all of the windows closed, the radio off, the
blower motor off, and all of the ventilation ducts open.
Most wind noise leaks will occur at the door and window seals or at the sheet metal joints in the door
or the door opening.
Symptom Chart SECTION 501-
00: Body System — General Information 2003 Mustang Workshop Manual Symptom Chart
Condition
Possible Sources Action
z Dust and
Water Leaks z
Body sealer missing.
z Opening in weldings
or body joints.
z Components not fully
installed.
z Components missing.
z Components
damaged. z
REMOVE trim panel. CHECK
for leaks and SEAL with
appropriate sealer. ROAD
TEST or WATER TEST for
leaks. RECHECK for leaks;
USE light under the vehicle
with trim removed. CHECK
interior of body at joints and
weld lines.
z Dust/Water
Leaks at Floor
Pan and
Grommets z
Missing or damaged
plugs and/or
grommets. z
CHECK plugs for proper
installation. REPLACE if
necessary.
z Door Drain
Holes
Collecting
Water z
Holes clogged with
mud or road tar. z
CLEAN drain holes of dirt and
foreign material. CHECK drain
holes regularly. TEST the
system for normal operation. Klj . 1 ba
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