horn FORD MUSTANG 2003 User Guide

Pinpoint Tests
PINPOINT TEST A: THE HORN DOES NOT SOUND module.
z Horn switch. Test Step Result / Action to
Take A1 CHECK POWER SUPPLY TO HORN RELAY
z
Disconnect: Horn Relay.
z Measure the voltage between the horn relay connector Pin 2,
Circuit 460 (YE/LB), harness side and ground; and between the
horn relay connector Pin 5, Circuit 460 (YE/LB), harness side and
ground.
z Are the voltages greater than 10 volts? Yes
GO to
A2 .
No
REPAIR the circuit in
question. TEST the
system for normal
operation. A2 CHECK HORN RELAY
z
Check the horn relay; refer to Wiring Diagrams Cell 149.
z Is the horn relay OK? Yes
GO to
A3 .
No
INSTALL a new horn
relay. TEST the
system for normal
operation. A3 CHECK HORN SWITCH SIGNAL TO HORN RELAY
z
Measure the resistance between horn relay connector Pin 1,
Circuit 6 (YE/LG), harness side and ground under the following
conditions:
Horn Switch Position Horn Switch Position Resistance
Pressed Less than 5 ohms
Released Greater than 10,000 ohms Yes
GO to
A4 .
No
GO to A5 . Klj . 2 ba
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z
Are the resistances correct? A4 CHECK WIRE BETWEEN HORN RELAY AND HORN
z
Key in OFF position.
z Disconnect: Horn C1262.
z Disconnect: Horn C1261.
z Measure the resistance between the horn relay connector Pin 3,
Circuit 1 (DB), harness side and horn C1261 or horn C1256
harness side; and between the horn relay connector Pin 3, Circuit
1 (DB), harness side and ground.
z Is the resistance less than 5 ohms between the horn relay and
the horns, and greater than 10,000 ohms between the horn
relay and ground? Yes
INSTALL new horns.
TEST the system for
normal operation.
No
REPAIR the circuit.
TEST the system for
normal operation.
A5 CHECK WIRE BETWEEN HORN RELAY AND AIR BAG SLIDING
CONTACT z
Key in OFF position.
z Deactivate the air bag system; refer to Section 501 - 20B .
z Disconnect: Air Bag Sliding Contact C218a.
z Measure the resistance between air bag sliding contact C218a Pin
2, Circuit 6 (YE/LG), harness side and horn relay connector Pin 1,
Circuit 6 (YE/LG) harness side.
z Is the resistance less than 5 ohms? Yes
GO to
A6 .
No
REPAIR the circuit.
TEST the system for
normal operation. A6 CHECK AIR BAG SLIDING CONTACT
z
Disconnect the steering wheel switch harness from the air bag
sliding contact.
z Measure the resistance between upper air bag sliding contact Yes
GO to
A7 . Klj . 3 ba
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PINPOINT TEST B: THE HORN SOUNDS CONTINUOUSLY connector Pin 3, Circuit 6 (component side), and air bag sliding
contact C218a Pin 2, Circuit 6 (component side).
z Is the resistance less than 5 ohms? No
INSTALL a new air
bag sliding contact.
REFER to
Section 501 - 20B . TEST the
system for normal
operation. A7 CHECK THE STEERING WHEEL SWITCH HARNESS
z
Inspect the steering wheel switch harness for chafing, opens or
possible short to ground.
z Is the steering wheel switch harness OK? Yes
INSTALL a new horn
switch. REFER to
Switch
— Horn . TEST
the system for normal
operation.
No
INSTALL a new
steering wheel switch
harness. TEST the
system for normal
operation. Test Step Result / Action to Take
B1 CHECK HORN CIRCUIT 1 (DB)
z
Key in OFF position.
z Disconnect: Horn Relay.
z Does the horn continue to sound? Yes
REPAIR Circuit 1 (DB) for short to battery. TEST
the system for normal operation.
No
GO to
B2 .
B2 CHECK HORN RELAY
z
Check the horn relay; refer to Wiring
Diagrams Cell 149.
z Is the horn relay OK? Yes
REINSTALL the horn relay. GO to
B3 .
No
INSTALL a new horn relay. TEST the system for
normal operation. B3 CHECK CIRCUIT 6 (YE/LG)
z
Disconnect: Air Bag Sliding Contact
C218a .
z Does the horn continue to sound? Yes
GO to
B4 .
No
RECONNECT the air bag sliding contact. GO to
B5 .
B4 CHECK GEM INPUT
z
Disconnect: GEM C201e. Yes Klj . 4 ba
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z
Does the horn continue to sound? REPAIR Circuit 6 (YE/LG). TEST the system for
normal operation.
No
INSTALL a new GEM; REFER to
Section 419 - 10 .
TEST the system for normal operation. B5 CHECK THE AIR BAG SLIDING
CONTACT z
Deactivate the air bag system. Refer
to Section 501 - 20B .
z Disconnect the steering wheel switch
harness from the air bag sliding
contact.
z Does the horn continue to sound? Yes
INSTALL a new air bag sliding contact. REFER to
Section 501
- 20B . TEST the system for normal
operation.
No
GO to B6 .
B6 CHECK STEERING WHEEL SWITCH
HARNESS z
Inspect the steering wheel switch
harness for shorts, opens, or any
damage.
z Is the steering wheel switch
harness OK? Yes
INSTALL a new horn switch. REFER to
Switch —
Horn . TEST the system for normal operation.
No
INSTALL a new steering wheel switch harness.
TEST the system for normal operation. Klj . 5 ba
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REMOVAL AND INSTALLATION
Switch —
Horn
Removal 1. Remove the driver side air bag module (043B13). Refer to Section 501 - 20B .
2. Remove the switches. 1. Disconnect the horn wire from the switches.
2. Remove the horn switch screws and remove the switches.
Installation 1. To install, reverse the removal procedure. zProve out the air bag system. Refer to Section 501 - 20B .
SECTION 413-
06: Horn 2003 Mustang Workshop Manual Klj . 1 ba
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Inspection and Verification
1. Verify the customer concern by operating the system.
2. Visually inspect for obvious signs of mechanical or electrical damage.
3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
4. If the diagnostic tool does not communicate with the vehicle, refer to the diagnostic tool manual.
5. Carry out the DATA LINK DIAGNOSTIC TEST. If the diagnostic tool responds with: zCKT 914, CKT 915 or CKT70 - ALL ECUS NO RESP/NOT EQUIP, refer to Section 418 -
00 .
z NO RESP/NOT EQUIP for the generic electronic module (GEM), go to Pinpoint Test A.
z NO RESP/NOT EQUIP for the instrument cluster module (ICM), refer to Section 413 - 01 .
z System passed, retrieve and record the continuous diagnostic trouble codes (DTCs),
erase the continuous DTCs and carry out self- test diagnostics for the GEM or ICM.
6. If the GEM or ICM DTCs retrieved are related to the concern, go to the GEM or ICM Diagnostic Trouble Code (DTC) Index.
7. If no DTCs related to the concern are retrieved, proceed to the Symptom Chart to continue diagnostics.
GEM DIAGNOSTIC TROUBLE CODE (DTC) INDEX Visual Inspection Chart Mechanical Electrical
z
Power window
regulator
z Window run
weatherstrip
z Door window glass z
Central junction box (CJB) circuit breaker 43 (20A), fuse 39
(5A) or 23 (15A)
z Battery junction box (BJB) fuse HTD BL (40A)
z Generic electronic module (GEM)
z Window regulator control switch
z Window regulator motor
z Instrument cluster module (ICM)
z Heated rear window relay
z Rear window defrost switch
z Heated rear window grid
z Circuitry DTC Description Source Action
B1217 Horn Relay Output Driver
Circuit Failure GEM GO to
Section 501 - 14B .
B1218 Horn Relay Output Driver
Short to Battery GEM GO to
Section 501 - 14B .
B1312 Lamp Headlamp Input Circuit GEM GO to
Section 413 - 09 . Klj . 2 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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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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