2003 FORD MUSTANG horn

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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4. If the concern remains after the inspection, connect the scan tool to the data link connector
(DLC) located beneath the instrument panel and select the vehicle to be tested from the scan
tool menu. If the scan tool does not communicate with the vehicle:
zcheck that the program card is correctly installed.
z check the connections to the vehicle.
z check the ignition switch position.
5. If the scan tool still does not communicate with the vehicle, refer to the scan tool manual.
6. Carry out the DATA LINK DIAGNOSTIC TEST. If the scan tool responds with: zCKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Section 418 -
00 .
z NO RESP/NOT EQUIP for GEM, go to Pinpoint Test A.
z SYSTEM PASSED, retrieve and record the continuous diagnostic trouble codes (DTCs),
erase the continuous DTCs, and carry out the self- test diagnostics for the GEM.
7. If the DTCs retrieved are related to the concern, go to the GEM Diagnostic Trouble Code (DTC) Index to continue diagnostics.
8. If no DTCs related to the concern are retrieved, proceed to Symptom Chart to continue diagnostics.
GEM Diagnostic Trouble Code (DTC) Index Mechanical Electrical
z
Binding latches z
CJB Fuses:
„39 (5A)
„ 19 (15A)
„ 25 (25A)
z BJB Fuse POWER WINDOWS (40A)
z Damaged wiring harness
z Loose or corroded connector(s)
z Circuitry open/shorted
z Damaged relays
z Remote transmitter
z Remote transmitter batteries DTC Description Source Action
B1217 Horn Relay Coil Circuit Failure GEM GO to
Pinpoint Test E .
B1218 Horn Relay Coil Circuit Short to
Vbatt GEM GO to
Pinpoint Test E .
B1312 Lamp Headlamp Input Circuit
Short to Battery GEM REFER to
Section 417 - 01 .
B1317 Battery Voltage High GEM REFER to
Section 414 - 00 .
B1318 Battery Voltage Low GEM REFER to
Section 414 - 00 .
B1322 Driver Door Ajar Circuit Short to
Ground GEM REFER to
Section 417 - 02 .
B1330 Passenger Door Ajar Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1334 Decklid Ajar Rear Door Circuit GEM REFER to
Section 417 - 02 . Klj . 3 ba
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Pinpoint Tests
PINPOINT TEST A: NO COMMUNICATION WITH THE GENERIC
ELECTRONIC MODULE z
Remote transmitter.
z Remote transmitter
batteries. Test C .
z The luggage compartment door
is inoperative using the remote
transmitter z
CJB Fuse 25 (25A).
z Remote transmitter
batteries.
z Remote transmitter.
z GEM.
z Circuitry.
z Luggage
compartment lid
release relay. z
GO to
Pinpoint Test D .
z Panic function does not operate
correctly z
GEM.
z Driver door unlock
relay.
z Circuitry.
z Remote transmitter
and batteries.
z Courtesy lamps.
z Horn relay.
z Horn.
z Parklamps. z
GO to
Pinpoint Test E .
Test Step Result / Action to Take
CAUTION: Use the correct probe adapter(s) when making measurements. Failure to
use the correct probe adapter(s) may damage the connector. A1 CHECK THE GENERIC ELECTRONIC MODULE (GEM)
POWER SUPPLY z
Key in OFF position.
z Disconnect: Generic Electronic Module (GEM) C201a.
z Disconnect: GEM C201b.
z Key in ON position.
z Using the following table, measure the voltage between the
GEM, harness side and ground.
z Are the voltages greater than 10 volts? Connector Pin Circuit
C201a 4 400 (LB/BK)
C201a 1 1006 (DG/WH)
C201b 2 1001 (WH/YE)
C201b 3 193 (YE/LG) Yes
GO to
A2 .
No
REPAIR the circuit(s) in
question. TEST the system
for normal operation. A2 CHECK THE GEM GROUND CIRCUIT 397 (BK/WH) FOR
OPEN z
Key in OFF position. Yes Klj . 6 ba
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normal operation.
E4 CHECK THE GEM OUTPUT TO THE HORN
z
Connect the diagnostic tool.
z Trigger the GEM active command HORN ON and OFF.
z Did the horn sound and turn off? Yes
GO to
E5 .
No
GO to E6 .
E5 CHECK THE GEM OUTPUT TO THE PARKING LAMPS
z
Connect the diagnostic tool.
z Trigger the GEM active command PARKLAMPS ON and
OFF.
z Did the parking lamps illuminate and turn off? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
GO to E10 .
E6 CHECK CIRCUIT 6 (YE/LG) FOR SHORT TO POWER
z
Disconnect: Horn Relay.
z Disconnect: GEM C201c.
z Measure the voltage between GEM C201c Pin 12, Circuit 6
(YE/LG), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
E7 .
No
REPAIR Circuit 6 (YE/LG).
REPEAT the self- test.
CLEAR the DTCs. E7 CHECK CIRCUIT 6 (YE/LG) FOR SHORT TO GROUND
z
Measure the resistance between GEM C201c Pin 12, Circuit
6 (YE/LG), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
E8 .
No
REPAIR Circuit 6 (YE/LG).
REPEAT the self- test.
CLEAR the DTCs. E8 CHECK CIRCUIT 6 (YE/LG) FOR OPEN
z
Measure the resistance between GEM C201c Pin 12, Circuit
6 (YE/LG), harness side and horn relay Pin 1, Circuit 6
(YE/LG), harness side. Yes
GO to
E9 .
No
REPAIR Circuit 6 (YE/LG).
REPEAT the self- test.
CLEAR the DTCs. Klj . 19 ba
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z
Is the resistance less than 5 ohms? E9 CHECK THE HORN FOR NORMAL OPERATION
z
Depress the steering wheel horn switch.
z Did the horn sound? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 -
10 . REPEAT the self-
test.
CLEAR the DTCs.
No
REFER to Section 413 -
06 .
E10 CHECK CIRCUIT 1032 (WH/BK) FOR SHORT TO POWER
z
Disconnect: Parking Lamp Relay.
z Disconnect: GEM C201e.
z Measure the voltage between GEM C201e Pin 11, Circuit
1032 (WH/BK), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
E11 .
No
REPAIR Circuit 1032
(WH/BK). REPEAT the
self- test. CLEAR the
DTCs. E11 CHECK CIRCUIT 1032 (WH/BK) FOR SHORT TO GROUND
z
Measure the resistance between GEM C201e Pin 11, Circuit
1032 (WH/BK), harness side and ground.
z Is the resistance greater than 10,000 ohms? Yes
GO to
E12 .
No
REPAIR Circuit 1032
(WH/BK). REPEAT the
self- test. CLEAR the
DTCs. E12 CHECK CIRCUIT 1032 (WH/BK) FOR OPEN
z
Measure the resistance between GEM C201e Pin 11, Circuit Yes Klj . 20 ba
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6. If the DTCs retrieved are related to the concern, go to GEM Diagnostic Trouble Code (DTC)
Index to continue diagnostics.
7. If no DTCs related to the concern are retrieved, proceed to Symptom Chart to continue diagnostics.
GEM Diagnostic Trouble Code (DTC) Index GEM Diagnostic Trouble Code (DTC) Index DTC Description Source Action
B1217 Horn Relay Coil Circuit Failure GEM REFER to
Section 413 - 06 .
B1218 Horn Relay Coil Circuit Short to
Vbatt GEM REFER to
Section 413 - 06 .
B1312 Lamp Headlamp Input Circuit
Short to Battery GEM REFER to
Section 417 - 01 .
B1317 Battery Voltage High GEM REFER to
Section 414 - 00 .
B1318 Battery Voltage Low GEM REFER to
Section 414 - 00 .
B1322 Driver Door Ajar Circuit Short to
Ground GEM REFER to
Section 417 - 02 .
B1330 Passenger Door Ajar Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1334 Decklid Ajar Rear Door Circuit
Short to Ground GEM REFER to
Section 417 - 02 .
B1339 Chime Input Request Circuit
Short to Battery (FOJ) GEM REFER to
Section 413 - 09 .
B1340 Chime Input Request Circuit
Short to Ground GEM REFER to
Section 413 - 09 .
B1342 ECU Is Defective GEM CLEAR the DTCs. Retrieve the DTCs. If DTC
B1342 is retrieved, INSTALL a new GEM. REFER to Section 419 - 10 .
B1353 Ignition Key-
In Circuit Open GEM REFER to
Section 413 - 09 .
B1359 Ignition Run/Acc Circuit Failure GEM REFER to
Section 211 - 05 .
B1396 Power Door Lock Circuit Short
to Battery GEM REFER to
Section 501 - 14B .
B1397 Power Door Unlock Circuit
Short to Battery GEM REFER to
Section 501 - 14B .
B1405 Driver Power Window Down
Circuit Short to Battery GEM REFER to
Section 501 - 11 .
B1408 Driver Power Window Up Circuit
Short to Battery GEM REFER to
Section 501 - 11 .
B1410 Driver Power Window Motor
Circuit Failure GEM REFER to
Section 501 - 11 .
B1426 Lamp Safety Belt Circuit Short
to Battery GEM REFER to
Section 413 - 01 .
B1428 Lamp Safety Belt Circuit Failure GEM REFER to
Section 413 - 01 .
B1431 Wiper Brake/Run Relay Circuit
Failure GEM GO to
Pinpoint Test B .
B1432 Wiper Brake/Run Relay Circuit GEM GO to
Pinpoint Test B . Klj . 3 ba
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Fuse/Relay BlockPower Distribution
Fusible LinksPower Distribution; Generators & Regulators;
Starters
GeneratorGenerators & Regulators; Engine Performance;
Power Distribution
Generic Electronic Module (GEM)Body Control Modules; Electronic Suspension
Glow Plug RelayEngine Performance
Glow PlugsEngine Performance
GroundsGround Distribution
Headlight Door ModuleHeadlight Doors
Headlight RelayHeadlight Systems; Daytime Running Lights
HeadlightsHeadlight Systems; Daytime Running Lights
Heated Oxygen Sensor(s) (HO2S)Engine Performance
Heated Windshield Control ModuleHeated Windshields
Height SensorElectronic Suspension
HornsSteering Column Switches
Horn RelaySteering Column Switches
Idle Air Control (IAC) Motor/ValveEngine Performance
Ignition Coil(s)Engine Performance
Ignition Key Lock CylinderAnti-Theft System
Ignition ModuleEngine Performance
Ignition SwitchPower Distribution; Engine Performance; Generators & Regulators; Starters
Illuminated Entry ModuleIllumination/Interior Lights
Illumination LightsIllumination/Interior Lights
Impact SensorAir Bag Restraint System
Inertia Fuel Shutoff SwitchEngine Performance
Inhibit RelayStarters
Instrument ClusterAnalog Instrument Panels
Intake Air Temperature (IAT) SensorEngine Performance
Interior LightsIllumination/Interior Lights
Interlock SwitchStarters
Junction BlockPower Distribution
Keyless Entry ReceiverRemote Keyless Entry
Key Reminder SwitchStarters
Knock SensorEngine Performance
Lamp Control ModuleExterior Lights
License Plate LampExterior Lights
Lighting Control ModuleLighting Control Modules; Anti-Theft System; Daytime Running Lights; Headlight Systems
Lower RelayPower Convertible Top
Malfunction Indicator Light (MIL)Engine Performance; Instrument Panels
Manifold Absolute Pr essure (MAP) SensorEngine Performance
Mass Airflow (MAF) SensorEngine Performance


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