2003 FORD MUSTANG wiring diagram

DIAGNOSIS AND TESTING
Communications Network
Refer to Wiring Diagrams Cell
14 , Multiplex Communication Network for schematic and connector
information.
Principles of Operation
The vehicle has two module communications networks. The standard corporate protocol (SCP) which
is an unshielded twisted pair cable (data bus plus, Circuit 914 [TN/OG] and data bus minus, Circuit 915
[PK/LB]), and the international standards organization (ISO) 9141 network which is a single wire
(Circuit 70 [LB/WH]). The diagnostic tool can connect to both networks through the data link connector
(DLC). This makes diagnosis and testing of these systems easier by allowing one smart tester to be
able to diagnose and control any module on the two networks from one connector. The DLC can be
found under the instrument panel between the steering column and the radio.
The ISO 9141 communication network does not permit inter- module communication. When the
diagnostic tool communicates to modules on the ISO 9141 communication network, the diagnostic tool
must ask for all information; the modules cannot initiate communications.
The SCP network will remain operational even with the severing of one of the bus wires.
Communications will also continue if one of the bus wires is shorted to ground or battery positive
voltage (B+) or if some, but not all, termination resistors are lost.
Unlike the SCP communication network, the ISO 9141 communication network will not function if the
wire is shorted to chassis ground or battery positive voltage (B+). Also, if one of the modules on the
ISO 9141 network loses power or shorts internally, communications to that module will fail.
The powertrain control module (PCM) is on the SCP communication network. The PCM controls the
engine for better fuel economy, emissions control, and failure mode detection and storage. Refer to
Powertrain Control/Emissions Diagnosis (PC/ED) manual Section 3 for diagnosis and testing of the
PCM.
The restraint control module (RCM) is on the ISO 9141 network. The RCM controls the deployment of
the air bags based on sensor input. For additional information, refer to Section 501 - 20B .
SECTION 418-
00: Module Communications Network 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
diagnostic tool Klj . 1 ba
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DIAGNOSIS AND TESTING
Anti-
Theft — Passive Anti- Theft System (PATS)
Refer to Wiring Diagrams Cell 112 , Anti-
Theft for schematic and connector information.
Refer to Wiring Diagrams Cell 60 , Instrument Cluster for schematic and connector information.
Inspection and Verification
NOTE: PATS must be reconfigured upon installment of a new instrument cluster. Refer to Section 418 -
00 .
1. Verify the customer concern by duplicating the condition.
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 the diagnostic tool does not communicate with the vehicle:
zcheck that the program card is correctly installed.
SECTION 419-
01: Anti-Theft — PATS 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter
105-
R0057 or equivalent Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent
diagnostic tool
Visual Inspection Chart Mechanical Electrical
z
Ignition lock cylinder
z Encoded ignition key (PATS key)
z Use of non- encoded ignition key (key without the molded plastic
head, non- PATS key)
z Use of a non- programmed encoded ignition key z
Central junction box
fuses:
„5 (15A)
„ 21 (5A)
„ 34 (20A)
z PATS transceiver
z Connectors
z Ignition switch Klj . 1 ba
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DIAGNOSIS AND TESTING
Rear View Mirrors
Refer to Wiring Diagrams Cell
124 , Power Mirrors for schematic and connector information.
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 concern is not visually evident, verify the symptom and refer to the Symptom Chart.
Symptom Chart
Refer to the Wiring Diagrams for connector numbers stated in the pinpoint tests. SECTION 501-
09: Rear View Mirrors 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter
105-
R0057 or equivalent Flex Probe Kit
105-
R025B or equivalent
Visual Inspection Chart Mechanical Electrical
z
Exterior rear view mirrors
z Interior rear view mirror z
Central junction box (CJB) fuse 19 (15A)
z Wiring harness
z Connections
z Exterior rear view mirror control
z Exterior rear view mirror motor
SYMPTOM CHART Condition
Possible Sources Action
z The mirrors are inoperative zExterior rear view
mirror control. z
Go To Pinpoint Test A . Klj . 1 ba
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DIAGNOSIS AND TESTING
Seats
Refer to Wiring Diagrams Cell
120 , Power Seats for schematic and connector information.
Refer to Wiring Diagrams Cell 122 , Power Lumbar Seats for schematic and connector information.
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 concern is not visually evident, verify the symptom. GO to Symptom Chart .
Symptom Chart
Refer to the Wiring Diagram manual for the connector numbers cited in the pinpoint tests. SECTION 501-
10: Seating 2003 Mustang Workshop Manual Special Tool(s)
73 III Automotive Meter
105-
R0057
Visual Inspection Chart Mechanical Electrical
z
Front seat track.
z Seat at limit(s) of travel. z
Battery junction box (BJB) Fuse Power Seat (25A).
z Loose, corroded or damaged connectors.
z Seat regulator control switch.
z Lumbar seat control switch.
z Lumbar motor.
z Bolster and lumbar control switches (cobra)
SYMPTOM CHART Condition
Possible Sources Action
z The power seat is
inoperative z
BJB Fuse Power Seat
(25A).
z Seat regulator control
switch.
z Circuitry. z
Go To Pinpoint Test
A . Klj . 1 ba
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PINPOINT TEST B: THE POWER SEAT DOES NOT MOVE
VERTICALLY —
FRONT z
Is the resistance less than 5 ohms? A3 CHECK THE SEAT REGULATOR CONTROL SWITCH
z
Carry out the seat regulator control switch component
test. Refer to Wiring Diagrams.
z Did the seat regulator control switch pass? Yes
CHECK for obstructed or binding
seat track. If no obstructions are
found, INSTALL a new seat
track. REFER to
Seat Track .
TEST the system for normal
operation.
No
INSTALL a new seat regulator
control switch. REFER to
Switch — Seat Regulator Control .
TEST the system for normal
operation. Test Step Result / Action to
Take B1 CHECK THE MOTOR SUPPLY CIRCUITS
z
Disconnect: Front Height Motor C382.
z NOTE: Make sure all connectors are connected on the seat.
z Measure the resistance between front height motor C382, Circuit
979 (RD/LB), harness side and ground and between front height
motor C382, Circuit 990 (YE/LB), harness side and ground.
z Are the resistances less than 5 ohms? Yes
GO to
B3 .
No
GO to B2 .
B2 CHECK CIRCUIT 979 (RD/LB) AND 990 (YE/LB) FOR AN OPEN
z
Disconnect: Seat Regulator Control Switch C360.
z Measure the resistance between front height motor C382, Circuit
979 (RD/LB), harness side and seat regulator control switch C360- 7, Yes
INSTALL a new
seat regulator Klj . 3 ba
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z
Is the resistance less than 5 ohms? F4 CHECK THE BOLSTER/LUMBAR SEAT CONTROL
SWITCHES z
Carry out the bolster/lumbar seat control switch component
test.
Refer to Wiring Diagrams Cell 149 for schematic and
connector information.
z Did the seat control switches pass? Yes
INSTALL a new
bolster/lumbar pump and
solenoid module. REFER to
Lumbar Motor
. TEST the
system for normal
operation.
No
INSTALL a new
bolster/lumbar seat control
switch. REFER to Lumbar Control Switch . TEST the
system for normal
operation. F5 CHECK THE LUMBAR ADJUSTING SYSTEM
z
Actuate the bolster/lumbar seat control switches to the
inflate position while observing the seat backrest lumbar
adjusting pad, backrest bolster and cushion bolster.
z Did the seat bolsters/lumbar adjusting pads inflate? Yes
GO to
F9 .
No
For seat backrest lumbar,
GO to F6 . For seat
backrest bolster, GO to
F10 . For seat cushion
bolster, GO to F14 .
F6 CHECK THE SEAT BACKREST LUMBAR ADJUSTING PAD
z
Visually inspect the seat backrest lumbar adjusting pad.
z Is the seat backrest lumbar adjusting pad damaged? Yes
INSTALL a new seat
backrest lumbar adjusting
pad. REFER to
Lumbar Assembly . TEST the
system for normal
operation.
No
GO to F7 .
F7 CHECK AIR FLOW FROM LUMBAR COMPRESSOR
z
Disconnect the seat backrest lumbar adjusting hose from
the connection at the seat pivot bolt.
z Actuate the lumbar seat control switch to the inflate position
while feeling for air at the connection.
z Is air felt at the lumbar motor hose connection? Yes
GO to
F8 .
No
INSTALL a new
bolster/lumbar pump and
solenoid module. REFER to Klj . 12 ba
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DIAGNOSIS AND TESTING
Glass, Frames and Mechanisms
Refer to Wiring Diagrams Cell
100 , Power Windows for schematic and connector information.
Refer to Wiring Diagrams Cell 56 , Rear Window Defrost for schematic and connector information.
Principles of Operation
Power Window Control
NOTE: Battery power and ground must be removed before disconnecting the GEM connectors to
avoid setting false DTCs.
The driver power window one- touch down operation is controlled by the generic electronic module
(GEM). This feature functions only when the ignition switch is in the RUN or ACCY positions. The GEM
determines ignition switch position by monitoring the key- in ignition, RUN/ACCY and RUN/START
circuits. The one-touch down operation is requested of the GEM by momentarily pressing the driver
window regulator control switch DOWN for 62 ms to 320 ms. The GEM uses the initial voltage input
from the down switch to begin the one- touch down operation. If the voltage input was less than 320
ms, the GEM will maintain the voltage supply to the motor down circuit. The GEM will maintain the
operation until:
zseven seconds expires.
z motor stall is detected by monitoring the current draw.
z a voltage input is received by the GEM on either the up or down switch circuits.
The ground for one- touch down operation does not pass through the GEM. The ground is supplied
through the driver window regulator control switch as with normal operation. If the GEM continues to
see voltage on the down circuit for more than 320 ms after initial activation the GEM will not effect
operation. The down circuit through the GEM is a direct connection to the motor in its normal state.
This allows the driver window regulator control switch to control the motor for normal operation.
The passenger window motors are hardwired directly to the window regulator control switches. SECTION 501-
11: Glass, Frames and Mechanisms 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent
diagnostic tool 73III Automotive Meter
105-
R0057 or equivalent Klj . 1 ba
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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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