2003 FORD MUSTANG wiring diagram

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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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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relay Pin 5, Circuit 65 (DG), harness side and ground; and
between BJB wiper ON/OFF relay Pin 2, Circuit 65 (DG),
harness side and ground.
z Are the voltages greater than 10 volts? REPAIR circuit(s) in question.
REPEAT the self-
test.
CLEAR the DTCs. B11 ISOLATE PROBLEM BETWEEN GEM AND BJB
z
Key in OFF position.
z Connect a fused jumper wire (30A) between wiper
ON/OFF relay Pin 3 and Pin 5, harness side.
z Key in ON position.
z Did the wiper motor activate? Yes
GO to
B12 .
No
GO to B22 .
B12 CARRY OUT THE WIPER ON/OFF RELAY COMPONENT
TEST z
Check the wiper ON and OFF relay; refer to Wiring
Diagrams, Cell 149, Component Testing.
z Is the ON/OFF wiper relay OK? Yes
GO to
B13 .
No
INSTALL a new wiper
ON/OFF relay. REPEAT the
self- test. CLEAR the DTCs. B13 CHECK CIRCUIT 646 (YE/WH) FOR SHORT TO
BATTERY BETWEEN GEM AND BJB z
Disconnect: Wiper On/Off Relay.
z Disconnect: GEM C201d.
z Measure the voltage between GEM C201d 3 Pin 12,
Circuit 646 (YE/WH), harness side and ground. Yes
REPAIR Circuit 646
(YE/WH). REPEAT the self-
test. CLEAR the DTCs.
No
GO to
B14 . Klj . 10 ba
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z
Connect a fused jumper wire (30A) between wiper
HIGH/LOW relay Pin 30, Circuit 61 (YE/RD), harness side
and Pin 87, Circuit 58 (WH), harness side.
z Did the wiper motor speed increase with the jumper
installed and slow down with the jumper removed? GO to
B18 .
No
GO to B26 .
B18 CARRY OUT COMPONENT TEST ON WIPER HIGH/LOW
RELAY z
Check the wiper HIGH/LOW relay; refer to Wiring
Diagrams, Cell 149, Component Testing.
z Is the wiper HIGH/LOW relay OK? Yes
GO to
B19 .
No
INSTALL a new wiper
HIGH/LOW relay. REPEAT
the self- test. CLEAR the
DTCs. B19 CHECK CIRCUIT 647 (GY/LB) FOR SHORT TO
BATTERY BETWEEN GEM AND BJB z
Disconnect: GEM C201d.
z Measure voltage between GEM C201d Pin 5, Circuit 647
(GY/LB), harness side and ground.
z Is the voltage greater than 10 volts? Yes
REPAIR Circuit 647 (GY/LB).
REPEAT the self-
test.
CLEAR the DTCs.
No
GO to B20 .
B20 CHECK CIRCUIT 647 (GY/LB) FOR SHORT TO GROUND
BETWEEN GEM AND BJB z
Measure the resistance between GEM C201d Pin 5,
Circuit 647 (GY/LB), harness side and ground. Yes
GO to
B21 .
No
REPAIR Circuit 647 (GY/LB).
REPEAT the self- test.
CLEAR the DTCs. Klj . 12 ba
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z
Is the resistance greater than 10,000 ohms? B21 CHECK CIRCUIT 647 (GY/LB) FOR OPEN CONDITION
BETWEEN GEM AND BJB z
Measure the resistance between GEM C201d Pin 5,
Circuit 647 (GY/LB), harness side and wiper HIGH/LOW
relay Pin 85, Circuit 647 (GY/LB), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new GEM.
REFER to
Section 419 - 10 .
REPEAT the self- test.
CLEAR the DTCs.
No
REPAIR Circuit 647 (GY/LB).
REPEAT the self- test.
CLEAR the DTCs. B22 CHECK CIRCUIT 61 (YE/RD) FOR OPEN CIRCUIT
CONDITION BETWEEN WIPER ON/OFF AND HIGH/LOW
RELAYS z
Disconnect: Wiper HIGH/LOW Relay.
z Disconnect: Wiper ON/OFF Relay.
z Measure the resistance between wiper ON/OFF relay Pin
3, Circuit 61 (YE/RD), harness side and wiper HIGH/LOW
relay Pin 30, Circuit 61 (YE/RD), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
B23 .
No
REPAIR Circuit 61 (YE/RD).
REPEAT the self- test.
CLEAR the DTCs. B23 CARRY OUT THE WIPER HIGH/LOW RELAY
COMPONENT TEST z
Check the wiper HIGH/LOW relay; refer to Wiring
Diagrams, Cell 149, Component Testing.
z Is the wiper HIGH/LOW relay OK? Yes
GO to
B24 .
No
INSTALL a new wiper
HIGH/LOW relay. REPEAT
the self- test. CLEAR the Klj . 13 ba
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test.
z Disconnect: Washer ON/OFF Relay.
z Measure the voltage between washer ON/OFF relay Pin 2, Circuit
65 (DG), harness side and ground; and washer ON/OFF relay Pin
3, Circuit 65 (DG), harness side and ground.
z Are the voltages greater than 10 volts? GO to
C5 .
No
REPAIR the circuit in
question. REPEAT
the self- test. CLEAR
the DTCs. C5 ISOLATE THE PROBLEM BETWEEN GEM AND BJB
z
Connect a fused jumper wire (30A) between washer ON/OFF
relay Pin 3, Circuit 65 (DG), harness side and Pin 5, Circuit 941
(BK/WH), harness side.
z Did the washer motor activate? Yes
GO to
C6 .
No
GO to C10 .
C6 CARRY OUT WASHER ON/OFF RELAY COMPONENT TEST
z
Check the washer ON/OFF relay; refer to Wiring Diagrams, Cell
149, Component Testing.
z Is the washer ON/OFF relay OK? Yes
GO to
C7 .
No
INSTALL a new wiper
ON/OFF relay.
REPEAT the self- test.
CLEAR the DTCs. C7 CHECK CIRCUIT 686 (TN/RD) FOR SHORT TO BATTERY
BETWEEN GEM AND BJB z
Disconnect: GEM C201d.
z Measure the voltage between GEM C201d Pin 6, Circuit 686
(TN/RD), harness side and ground. Yes
REPAIR Circuit 686
(TN/RD). REPEAT the
self-
test. CLEAR the
DTCs.
No
GO to C8 . Klj . 16 ba
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DIAGNOSIS AND TESTING
Convertible Top
Refer to Wiring Diagrams Cell
103 , for schematic and connector information.
Principles of Operation
The convertible top will only operate with the parking brake engaged and the ignition switch in the RUN
position. When the parking brake is engaged, the raise and lower relay coils are grounded through the
parking brake switch. The convertible top switch supplies power to the raise or lower relay coil when
raise or lower is selected. This power energizes the coil causing the relay contacts to close which
supplies battery power to the convertible top motor/pump assembly. The normal state of the relay is
connected to ground. When the raise or lower relay is operating, the other relay remains in its normal
state supplying the motor/pump ground.
Convertible Top Adjustments
The convertible top adjustments must be made by a qualified technician.
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.
SECTION 501-
18: Convertible Top 2003 Mustang Workshop Manual Special Tool(s)
73 III Automotive Meter
105-
R0057 or equivalent
Visual Inspection Chart Mechanical Electrical
z
Convertible top brackets and
frame
z Hydraulic motor and pump
z Hydraulic lift cylinders
z Door and quarter window glass
adjustment z
Central junction box (CJB) Fuse 20 (15A)
z Battery junction box (BJB) circuit breaker
CONV TOP (30A)
z Wiring harness
z Loose or corroded connections
z Raise or lower relays
z Parking brake switch
z Convertible top switch Klj . 1 ba
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DIAGNOSIS AND TESTING
Air Bag Supplemental Restraint System (SRS)
Refer to Wiring Diagrams Cell
46 , Air Bag for schematic and connector information.
Restraint System Diagnostic Tool Warning WARNING: This tool is for restraint system service only. Remove from vehicle prior to
road use. Failure to remove could result in injury and possible violation of vehicle safety
standards.
Diagnosing Customer Concerns Without Hard DTCs
If a lamp fault code (LFC) is reported by the customer but is not present when the vehicle comes in for
service, follow the Diagnostic Instructions procedure in this section to identify the intermittent DTC.
Once the DTC is known, read the Normal Operation section of the pinpoint test for the DTC involved.
zFollow the deactivation procedure in this section.
z Determine the location of components involved in creating that code.
z Perform a thorough visual inspection of:
„components.
„ connectors.
„ splices and wiring harnesses.
„ pinched wires.
„ worn insulation on conductors.
Refer to the Possible Causes section of the pinpoint test for the DTC involved, which lists the common
concerns that relate to the DTC. Concerns are listed according to priority.
Diagnosing Customer Concerns with Hard DTCs
WARNING: The restraint system diagnostic tool is for restraint system service only.
Remove from vehicle prior to road use. Failure to remove could result in injury and possible
violation of vehicle safety standards. SECTION 501-
20B: Supplemental Restraint System 2003 Mustang Workshop Manual Special Tool(s)
Diagnostic Tool, Restraint
System
418-
F088 (105- R0012) Klj . 1 ba
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