2003 FORD MUSTANG relay

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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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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Short to Ground
B1339 Chime Input Request Circuit
Short to Battery 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 DTC. 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 GO to
Pinpoint Test B .
B1397 Power Door Unlock Circuit
Short to Battery GEM GO to
Pinpoint Test B .
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 .
B1833 Door Unlock Disarm Switch
Circuit Short to Ground GEM REFER to
Section 419 - 01 .
B1498 Decklid Punch-Out Sensor
Ground Short. GEM GO to
Pinpoint Test D .
B1603 Lamp Anti-
Theft Indicator
Circuit Failure GEM REFER to
Section 413 - 01 .
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 REFER to
Section 501 - 16 .
B1432 Wiper Brake/Run Relay Circuit
Short to Battery GEM REFER to
Section 501 - 16 .
B1434 Wiper Hi/Low Speed Relay Coil
Circuit Failure GEM REFER to
Section 501 - 16 .
B1436 Wiper Hi/Low Speed Relay Coil
Circuit Short to Battery GEM REFER to
Section 501 - 16 .
B1438 Wiper Mode Select Switch
Circuit Failure GEM REFER to
Section 501 - 16 .
B1441 Wiper Mode Select Switch
Circuit Short to Ground GEM REFER to
Section 501 - 16 .
B1446 Wiper Park Sense Circuit
Failure GEM REFER to
Section 501 - 16 .
B1448 Wiper Park Sense Circuit Short
to Battery GEM REFER to
Section 501 - 16 .
B1450 Wiper Wash/Delay Switch
Circuit Failure GEM REFER to
Section 501 - 16 .
B1453 Wiper Wash/Delay Switch
Circuit Short to Ground GEM REFER to
Section 501 - 16 . Klj . 4 ba
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Symptom Chart B1458 Wiper Washer Pump Motor
Relay Circuit Failure GEM REFER to
Section 501 - 16 .
B1460 Wiper Washer Pump Motor
Relay Coil Circuit Short to Battery GEM REFER to
Section 501 - 16 .
B1462 Safety Belt Switch Circuit
Failure GEM REFER to
Section 413 - 09 .
B1466 Wiper Hi/Low Speed Not
Switching GEM REFER to
Section 501 - 16 .
B1473 Wiper Low Speed Circuit Motor
Failure GEM REFER to
Section 501 - 16 .
B1476 Wiper High Speed Circuit Motor
Failure GEM REFER to
Section 501 - 16 .
B1551 Decklid Release Circuit Failure GEM GO to
Pinpoint Test D .
B1553 Decklid Release Circuit Short
to Battery GEM GO to
Pinpoint Test D .
B1555 Ignition Run/Start Circuit
Failure GEM REFER to
Section 211 - 05 .
B1687 Lamp Dome Input Circuit Short
to Battery GEM REFER to
Section 417 - 02 .
B2486 LF Side Repeater Lamp Output
Circuit Failure GEM REFER to
Section 417 - 01 .
B1605 Lamp Anti-
Theft Indicator
Circuit Short to Battery GEM REFER to
Section 501 - 16 .
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
Circuitry.
z CJB Fuse 39 (5A).
z GEM. z
GO to
Pinpoint Test A .
z All door locks are inoperative zCJB Fuse 19 (15A).
z BJB Fuse POWER
WINDOWS (40A).
z Circuitry.
z GEM.
z Switches.
z Lock actuators. z
GO to
Pinpoint Test B .
z The doors do not lock/unlock
using the remote transmitter z
Ignition switch.
z GEM. z
GO to
Pinpoint Klj . 5 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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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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relay Pin 5 Circuit 931 (OG), harness side and ground
z Is the voltage greater than 10 volts? REPAIR Circuit 931 (OG).
REPEAT the self-
test. CLEAR
the DTCs. D7 BYPASS THE GEM AND RELAY CONTROL
z
Momentarily connect a 25A jumper wire between the
luggage compartment lid release relay Pin 3 and Pin 5.
z Did the luggage compartment lid release? Yes
GO to
D8 .
No
GO to D12 .
D8 CHECK LUGGAGE COMPARTMENT LID RELEASE
RELAY z
Carry out the luggage compartment lid release relay.
REFER to Wiring Diagrams Cell 149, Component
Testing.
z Is the luggage compartment lid release relay OK? Yes
GO to
D9 .
No
INSTALL a new luggage
compartment lid release relay.
REPEAT the self- test. CLEAR
the DTCs. D9 CHECK CIRCUIT 599 (PK/LG) FOR SHORT TO POWER
z
Disconnect: GEM C201c.
z Measure the voltage between GEM C201c Pin 25, Circuit
599 (PK/LG), harness side and ground.
z Is the voltage greater than 10 volts? Yes
REPAIR Circuit 599 (PK/LG).
REPEAT the self-
test. CLEAR
the DTCs.
No
GO to D10 .
D10 CHECK CIRCUIT 599 (PK/LG) FOR SHORT TO
GROUND z
Measure the resistance between GEM C201c Pin 25, Yes Klj . 16 ba
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Circuit 599 (PK/LG), harness side and ground.
z Is the resistance greater than 10,000 ohms? GO to
D11 .
No
REPAIR Circuit 599 (PK/LG).
REPEAT the self- test. CLEAR
the DTCs. D11 CHECK CIRCUIT 599 (PK/LG) FOR OPEN
z
Measure the resistance between GEM C201c Pin 25,
Circuit 599 (PK/LG), harness side and luggage
compartment lid release relay Pin 1, Circuit 599 (PK/LG),
harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new GEM. For
additional information, REFER
to
Section 419 - 10 . REPEAT
the self- test. CLEAR the
DTCs.
No
REPAIR Circuit 599 (PK/LG).
REPEAT the self- test. CLEAR
the DTCs. D12 CHECK CIRCUIT 84 (VT/YE) FOR SHORT TO POWER
z
Disconnect: GEM C201c.
z Measure the voltage between luggage compartment lid
release relay Pin 3, Circuit 84 (VT/YE), harness side and
ground.
z Is the voltage greater than 10 volts? Yes
REPAIR Circuit 84 (VT/YE).
REPEAT the self-
test. CLEAR
the DTCs.
No
GO to D13 .
D13 CHECK CIRCUIT 84 (VT/YE) FOR OPEN
z
Disconnect: Luggage Compartment Lid Release Solenoid
C430.
z Measure the resistance between luggage compartment
lid release relay Pin 3, Circuit 84 (VT/YE), harness side
and luggage compartment lid release solenoid C430 Pin
2, Circuit 84 (VT/YE), harness side. Yes
GO to
D14 .
No
REPAIR Circuit 84 (VT/YE).
REPEAT the self- test. CLEAR
the DTCs. Klj . 17 ba
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