2003 FORD MUSTANG wiring

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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z
Is the voltage greater than 10 volts? REPAIR Circuit 326
(WH/VT). REPEAT
the self-
test. CLEAR
the DTCs. B4 CHECK THE DRIVER POWER DOOR LOCK SWITCH FOR
CORRECT OPERATION z
Carry out the master window/door lock control switch component
test. REFER to Wiring Diagrams Cell 149, Component Testing.
z Is the master window/door lock control switch OK? Yes
GO to
B5 .
No
INSTALL a new
master window/door
lock control switch.
REPEAT the self-
test. CLEAR the
DTCs. B5 CHECK CIRCUITS 129 (LG) AND 1014 (VT) FOR SHORT TO
POWER z
Key in OFF position.
z Disconnect: GEM C201c.
z Measure the voltage between GEM C201c Pin 20, Circuit 129 (LG),
harness side and ground; and between GEM C201c Pin 18, Circuit
1014 (VT), harness side and ground.
z Key in ON position.
z Measure the voltage between GEM C201c Pin 20, Circuit 129 (LG),
harness side and ground; and between GEM C201c Pin 18, Circuit
1014 (VT), harness side and ground.
z Key in OFF position.
z Are the voltages greater than 10 volts? Yes
REPAIR the circuit in
question. REPEAT
the self-
test. CLEAR
the DTCs.
No
GO to B6 . Klj . 8 ba
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B6 CHECK CIRCUITS 129 (LG) AND 1014 (VT) FOR OPEN
z
Measure the resistance between master window/door lock control
switch C508 Pin 4, Circuit 129 (LG), harness side and GEM C201c
Pin 20, Circuit 129 (LG), harness side; and between master
window/door lock control switch C508 Pin 2, Circuit 1014 (VT),
harness side and GEM C201c 2 Pin 18, Circuit 129 (LG), harness
side.
z Are the resistances 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 the circuit in
question. REPEAT
the self- test. CLEAR
the DTCs. B7 CHECK CIRCUIT 326 (WH/VT) FOR VOLTAGE —
PASSENGER
SIDE z
Disconnect: Passenger Window/Door Lock Control Switch C629.
z Measure the voltage between passenger/window door lock control
switch C629 Pin 3, Circuit 326 (WH/VT), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
B8 .
No
REPAIR Circuit 326
(WH/VT). REPEAT
the self- test. CLEAR
the DTCs. B8 CHECK THE PASSENGER POWER DOOR LOCK SWITCH FOR
CORRECT OPERATION z
Carry out the passenger window/door lock control switch
component test. REFER to Wiring Diagrams Cell 149, Component
Testing.
z Is the master window/door lock control switch OK? Yes
GO to
B9 .
No
INSTALL a new
master window/door
lock control switch.
REPEAT the self-
test. CLEAR the
DTCs. B9 CHECK CIRCUITS 119 (PK/YE) AND 120 (PK/LG) FOR SHORT TO
POWER z
Disconnect: GEM C201c.
z Measure the voltage between GEM C201c Pin 19, Circuit 119
(PK/YE), harness side and ground; and between GEM C201c Pin
17, Circuit 120 (PK/LG), harness side and ground. Yes
REPAIR the circuit in
question. REPEAT
the self-
test. CLEAR
the DTCs.
No
GO to B10 . Klj . 9 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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DIAGNOSIS AND TESTING
Wipers and Washers
Refer to Wiring Diagrams Cell
59 , Generic Electronic Module for schematic and connector
information.
Refer to Wiring Diagrams Cell 81 , Interval Wiper/Washer for schematic and connector information.
Principles of Operation
Multifunction Wipers
The front wiper/washer feature controls the speed of the front windshield wipers and the amount of
washer fluid sprayed on the front windshield when requested by the customer. There are five (5) wiper
modes: OFF, LOW, HIGH, INTERVAL, and WASH.
Wiper Motor Speeds HIGH and LOW
There are two wiper speeds, HIGH and LOW. When the GEM detects the ignition switch circuits are in
the RUN or ACC states, and the GEM detects a high or low speed request from the wiper mode
circuits, the GEM will activate the wiper ON and OFF and the wiper speed circuits accordingly.
Wiper Motor Speeds Interval
There are one to seven wiper speed intervals, ranging from 1.5 seconds to 20 seconds in delay time
respectively, which can be selected. When the GEM detects the ignition switch circuits are in the RUN
or ACC states, and the GEM detects an interval selection of 1 through 7 from the delay/wash circuits, the GEM will activate the wiper ON and OFF and the wiper speed circuits accordingly. SECTION 501-
16: Wipers and Washers 2003 Mustang Workshop Manual Special Tool(s)
Alternator, Regulator, Battery
and Starter Tester (ARBST) or
equivalent
010-
00725 73 Digital Multimeter or
equivalent
105-
R0051 Worldwide Diagnostic System
(WDS)
418-
F224
New Generation STAR (NGS)
Tester
418- F052, or equivalent
diagnostic tool Klj . 1 ba
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Washers
When the GEM detects the ignition switch circuits are in RUN or ACC states, and the GEM detects a
WASH request from the wiper delay/wash circuits, the GEM will activate the washer pump relay circuit
for as long as the request is present up to 10 seconds.
Activation of the washer pump when in INTERVAL or OFF is delayed until a wash request is active for
a minimum amount of time. In this scenario, the wash request must be present continuously for at least
210 ms. This allows a wash request that is present for less than 210 ms, to provide additional
functionality by initiating a single wipe, called "mist wipe". The mist wipe function is a single wipe at low
speed without activating the washer motor.
When in LOW or HIGH, any WASH request, regardless of the length of time it is present, will activate
the washer pump. When in INTERVAL or OFF mode, upon deactivation of the washer motor, this
feature shall provide two wipes at low speed before returning to the INTERVAL or OFF state as
defined by the inputs. These additional wipes are provided to clear residual washer fluid from the front
windshield.
Inspection and Verification
1. Verify the customer concern by operating the wiper/washer system.
2. Visually inspect for obvious signs of mechanical and electrical damage.
3. If the concern remains after the inspection, connect the diagnostic tool to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the
diagnostic tool menu. If diagnostic 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.
4. If diagnostic tool still does not communicate with the vehicle, refer to the diagnostic tool manual.
5. Carry out the DATA LINK DIAGNOSTIC TEST. If diagnostic tool responds with: zCKT914, CKT915 or CKT70 = ALL ECUS NO RESP/NOT EQUIP, refer to Section 418 -
00 .
z NO RESPONSE/NOT EQUIPPED 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 self- test diagnostics for the GEM.
Visual Inspection Chart Mechanical Electrical
z
Hoses to windshield washer pump
z Wiper linkage z
CJB Fuse 39 (5A)
z CJB Fuse 26 (30A)
z Wiring harness
z Loose or corroded connector(s)
z Relays
z Motors
z Multifunction switch
z GEM Klj . 2 ba
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No
GO to
B10 .
B4 TEST THE GEM CONTROL OF WIPER HIGH/LOW RELAY
z
Trigger the GEM active command WIPER RLY to ON.
z Trigger the GEM active command SPEED RLY ON and
OFF.
z Does wiper speed change on activation and
deactivation of SPEED RLY command? Yes
GO to
B5 .
No
GO to B16 .
B5 DETERMINE IF GEM IS RECEIVING CORRECT WIPER
POSITION STATUS z
Monitor GEM PID WPPRKSW while turning the wipers ON
using the multifunction switch.
z Do the PID values agree with the wiper position? Yes
INSTALL a new GEM. For
additional information,
REFER to
Section 419 - 10 .
CLEAR the DTCs. REPEAT
the self- test.
No
GO to B27 .
B6 TEST THE MULTIFUNCTION SWITCH FOR NORMAL
OPERATION z
Disconnect: Multifunction Switch C202a.
z Check the multifunction switch. Refer to Wiring Diagrams,
Cell 149, Component Testing.
z Is the multifunction switch OK? Yes
GO to
B7 .
No
INSTALL a new multifunction
switch; REFER to Section 211 - 05 . REPEAT the self-
test. CLEAR the DTCs. B7 CHECK CIRCUITS 682 (DB), 684 (PK/YE), AND 680
(LB/OG) FOR SHORT TO BATTERY BETWEEN THE GEM
AND THE MULTIFUNCTION SWITCH z
Disconnect: GEM C201e.
z Key in ON position.
z Using the following table, measure the voltage between
the GEM C201e Pins, harness side and ground.
z Are the voltages greater than 10 volts? Pin Circuit
5 682 (DB)
18 684 (PK/YE)
19 680 (LB/OG) Yes
REPAIR the circuit(s) in
question. REPEAT the self-
test. CLEAR the DTCs.
No
GO to
B8 .
B8 CHECK CIRCUITS 682 (DB), 684 (PK/YE), AND 680 Klj . 8 ba
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