2003 FORD MUSTANG diagram

Symptom Chart
Refer to the Wiring Diagrams for the connector numbers stated in pinpoint tests.
Symptom Chart Condition
Possible Sources Action
z No communication with the
generic electronic module
(GEM) z
Central junction box
(CJB) fuse 39 (5A).
z GEM.
z Circuitry. z
GO to Pinpoint Test A .
z All power windows are
inoperative — convertible z
Circuitry.
z CJB circuit breaker
43 (20A).
z Window regulator
control switch. z
GO to Pinpoint Test B .
z All power windows are
inoperative — coupe z
Circuitry.
z CJB circuit breaker
43 (20A).
z Window regulator
control switch. z
GO to Pinpoint Test C .
z A single power window is
inoperative — driver,
convertible z
Circuitry.
z CJB fuse 43 (20A).
z Ignition switch.
z Window regulator
motor.
z Window regulator
control switch.
z GEM. z
GO to Pinpoint Test D .
z A single power window is
inoperative — driver, coupe z
Circuitry.
z CJB fuse 43 (20A).
z Ignition switch.
z Window regulator
motor.
z Window regulator
control switch.
z GEM. z
GO to Pinpoint Test E .
z The one- touch down feature
is inoperative z
Circuitry.
z CJB fuse 43 (20A).
z Ignition switch.
z Window regulator
motor.
z Window regulator
control switch.
z GEM. z
For convertible,
GO to Pinpoint Test D .
z For coupe, GO to
Pinpoint Test E .
z A single power window is
inoperative — passenger z
Circuitry.
z Driver window
regulator control
switch.
z Window regulator
motor.
z Passenger window
regulator control
switch. z
GO to Pinpoint Test F .
z A single power window is zCircuitry. zGO to Pinpoint Klj . 5 ba
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z
Is the resistance less than 5 ohms? D5 CHECK THE DRIVER WINDOW REGULATOR CONTROL
SWITCH z
Carry out the driver window regulator control switch
component test. Refer to the Wiring Diagrams Cell 149,
Component Testing.
z Did the driver window regulator control switch pass? Yes
GO to
D6 .
No
INSTALL a new driver
window regulator control
switch. REFER to
Switch — Window
Regulator Control in this
section. TEST the system
for normal operation. D6 CHECK CIRCUIT 226 (WH/BK) FOR A SHORT TO BATTERY
z
Key in OFF position.
z Disconnect: GEM C201a.
z Measure the voltage between GEM C201a pin 2, circuit 226
(WH/BK), harness side and ground.
z Key in ON position.
z Measure the voltage between GEM C201a pin 2, circuit 226
(WH/BK), harness side and ground.
z Is either voltage greater than 10 volts? Yes
REPAIR the circuit. TEST
the system for normal
operation.
No
GO to
D7 .
D7 CHECK CIRCUIT 991 (TN/LB) AND 992 (WH/BK) FOR AN
OPEN Klj . 10 ba
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position while monitoring PIDs.
z Did the PID values agree with the ignition switch positions? No
REFER to
Section 211 -
05 for ignition switch
diagnosis. E2 CHECK THE DRIVER WINDOW REGULATOR CONTROL
SWITCH INPUT TO THE GEM z
Key in ON position.
z Enter the following diagnostic mode on the diagnostic tool: GEM
PID D_UP_SW and D_DN_SW.
z Actuate the driver window regulator control switch to the UP and
DOWN position.
z Did the PID values agree with the driver window regulator
control switch positions? Yes
GO to
E9 .
No
GO to E3 .
E3 CHECK THE POWER SUPPLY TO THE WINDOW REGULATOR
CONTROL SWITCH z
Disconnect: Driver Window Regulator Control Switch C508.
z Key in ON position.
z Measure the voltage between driver window regulator control
switch C508 pin 10, circuit 400 (LB/BK), harness side and
ground.
z Is the voltage greater than 10 volts? Yes
GO to
E4 .
No
GO to E8 .
E4 CHECK CIRCUIT 1205 (BK) FOR AN OPEN
z
Measure the resistance between driver window regulator control
switch C508 pin 7, circuit 1205 (BK), harness side and ground;
and between driver window regulator control switch C508 pin
12, circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
GO to
E5 .
No
REPAIR the circuit.
TEST the system for
normal operation. E5 CHECK THE DRIVER WINDOW REGULATOR CONTROL
SWITCH z
Carry out the driver window regulator control switch component
test. Refer to the Wiring Diagrams Cell 149, Component
Testing.
z Did the driver window regulator control switch pass? Yes
GO to
E6 .
No
INSTALL a new driver Klj . 14 ba
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z
Is the resistance less than 5 ohms? section. TEST the system
for normal operation.
No
REPAIR the circuit. TEST
the system for normal
operation.
F13 CHECK CIRCUIT 333 (YE/RD) FOR AN OPEN
z
Measure the resistance between passenger window regulator
control switch C629 pin 10, circuit 333 (YE/RD), harness side
and passenger window regulator motor C623, circuit 333
(YE/RD), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new
passenger window
regulator control switch.
TEST the system for
normal operation.
No
REPAIR the circuit. TEST
the system for normal
operation.
F14 CHECK THE DRIVER WINDOW REGULATOR CONTROL
SWITCH z
Carry out the driver window regulator control switch
component test. REFER to Wiring Diagrams Cell 149,
Component Testing.
z Is the driver window regulator control switch OK? Yes
INSTALL a new
passenger window
regulator motor. REFER
to
Motor — Window
Regulator in this section.
TEST the system for
normal operation.
No
INSTALL a new driver
window regulator control
switch. REFER to
Switch — Window
Regulator Control in this
section. TEST the system
for normal operation. F15 CHECK THE POWER SUPPLY TO THE PASSENGER
WINDOW REGULATOR CONTROL SWITCH z
Key in OFF position.
z Disconnect: Passenger Window Regulator Control Switch
C629.
z Key in ON position.
z Measure the voltage between passenger window regulator
control switch C629 pin 8, circuit 194 (PK), harness side and
ground. Yes
INSTALL a new
passenger window
regulator control switch.
TEST the system for
normal operation.
No Klj . 22 ba
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PINPOINT TEST H: THE DEFROST SYSTEM IS INOPERATIVE G5 CHECK DRIVER WINDOW REGULATOR CONTROL SWITCH
z
Disconnect: Driver Window Regulator Control Switch C537.
z Carry out the driver window regulator control switch component test.
REFER to Wiring Diagrams Cell 149, Component Testing.
z Is the driver window regulator control switch OK? Yes
INSTALL a new
rear window
regulator motor.
REFER to
Motor —
Window Regulator,
Quarter in this
section. TEST the
system for normal
operation.
No
INSTALL a new
driver window
regulator control
switch. REFER to
Switch — Window
Regulator Control in
this section. TEST
the system for
normal operation. Test Step Result / Action to Take
H1 CHECK POWER TO INDICATOR LIGHT
z
Key in ON position.
z Depress the rear window defrost switch to ON.
z Is the rear window defrost switch indicator ON? Yes
GO to
H2 .
No
GO to H3 .
H2 CHECK CIRCUIT 186 (BR/LB) FOR AN OPEN
z
Key in OFF position.
z Disconnect: Heated Rear Window Relay.
z Disconnect: Heated Rear Window Grid Power Supply
Connector C402a.
z Measure the resistance between heated rear window relay,
circuit 186 (BN/LB), harness side and heated rear window
grid C402a, circuit 186 (BN/LB), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
H7 .
No
REPAIR the circuit. TEST
the system for normal
operation. H3 CHECK THE DIAGNOSTIC TROUBLE CODES (DTCS)
z
Refer to the results from the previous instrument cluster
module (ICM) self- test.
z Was DTC B1343 retrieved? Yes
GO to
H4 . Klj . 25 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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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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