diagram FORD MUSTANG 2003 User Guide

DIAGNOSIS AND TESTING
Starting System
Refer to Wiring Diagrams Cell
20 , Starting System for schematic and connector information.
Inspection and Verification WARNING: When servicing starter motor or carrying out other underhood work in the
vicinity of the starter motor, be aware that the heavy gauge battery input lead at the starter
solenoid is "electrically hot" at all times. A protective cap or boot is provided over this terminal
that must be installed after servicing. Be sure to disconnect the battery negative cable before
servicing the starter. Failure to follow these instructions may result in personal injury.
WARNING: When working in area of the starter motor, be careful to avoid touching hot
exhaust components. Failure to follow these instructions may result in personal injury.
WARNING: When using a remote starter switch or jumper wire, be sure the ignition switch
is in the OFF position and the transmission is in PARK (A/T) or Neutral (M/T) with the parking
brake control fully applied.
1. Verify the customers concern by operating the starting system to duplicate the conditions.
2. Inspect to determine if any of the following mechanical or electrical concerns apply.
3. If the inspection reveals an obvious concern that can be readily identified, repair as necessary.
4. If the concern remains after the inspection, determine the symptom. GO to Symptom Chart .
SECTION 303-
06: Starting System 2003 Mustang Workshop Manual Special Tool(s)
Digital Multimeter
105-
R0051 or equivalent Visual Inspection Chart
Mechanical Electrical
z
Starter motor
z Brackets z
Battery
z Battery junction box (BJB) fuse ignition switch (40A)
z Central junction box (CJB) Fuse 6 (20A)
z Fuse 24 (10A)
z Damaged wiring harness
z Starter Relay
z Loose or corroded connections Klj . 1 ba
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z
Measure the voltage between the central junction box fuse 6,
circuit 33 (WH/PK) and ground while holding the key in the
START position.
z Is the voltage greater than 10 volts? system for normal
operation.
No
GO to
B8 .
B8 CHECK CIRCUIT 1050 (LG/VT) FOR VOLTAGE
z
Key in OFF position.
z Disconnect: Ignition Switch C209.
z Key in ON position.
z Measure the voltage between the ignition switch connector
C209 pin B4, circuit 1050 (LG/VT) and ground.
z Is the voltage greater than 10 volts? Yes
GO to
B9 .
No
REPAIR circuit 1050
(LG/VT). TEST the
system for normal
operation. B9 CHECK THE IGNITION SWITCH
z
Carry out the ignition switch component test. Refer to
Refer to Wiring Diagrams Cell 149 for schematic and connector
information.
.
z Does the ignition switch test good? Yes
REPAIR circuit 33
(WH/PK). TEST the
system for normal
operation.
No
INSTALL a new ignition
switch. TEST the
system for normal
operation.
B10 CHECK CIRCUIT 1205 (BK) FOR OPEN
z
Key in OFF position. Yes
INSTALL a new starter
motor relay. TEST the
system for normal
operation.
No
REPAIR circuit 1205
(BK). TEST the system
for normal operation. Klj . 6 ba
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DIAGNOSIS AND TESTING
Diagnostic Strategy
Troubleshooting an electronically controlled automatic transmission is simplified by using the proven
method of diagnosis. One of the most important things to remember is that there is a definite
procedure to follow.
NOTE:
Do not take any short cuts or assume that critical checks or adjustments have already been
made.
Follow the procedures as written to avoid missing critical components or steps.
To properly diagnose a concern have the following publications available:
zTransmission Reference Manual.
z Powertrain Control/Emissions Diagnosis (PC/ED) manual.
z TSBs and OASIS Messages.
z Wiring Diagram.
These publications provide the information required when diagnosing transmission concerns.
Use the Diagnostic Flow Chart as a guide and follow the steps as indicated.
Preliminary Inspection
zKnow and understand the customer's concern.
z Verify the concern by operating the vehicle.
z Check the fluid levels and condition.
z Check for non-factory add- on items.
z Check shift linkages for proper adjustment.
z Check TSBs and OASIS messages regarding the concern.
Diagnostics
zCarry out on- board diagnostic procedures key on engine off (KOEO) and key on engine running
(KOER).
z Record all diagnostic trouble codes (DTCs).
z Repair all non- transmission codes first.
z Repair all transmission codes second.
z Erase all continuous codes and attempt to repeat them.
z Repair all continuous codes.
z If only pass codes are obtained, refer to Diagnosis By Symptom for further information and
diagnosis.
Follow the diagnostic sequence to diagnose and repair the concern the first time. SECTION 307-
01: Automatic Transaxle/Transmission 2003 Mustang Workshop Manual Klj . 1 ba
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DIAGNOSIS AND TESTING
External Controls
Refer to Wiring Diagrams Cell
37 , Shift Lock for schematic and connector information.
Refer to Wiring Diagrams Cell 29 , Transmission Control for schematic and connector information.
Inspection and Verification 1. Verify the customer concern by operating the transmission external control.
2. Visually inspect for obvious signs of mechanical and electrical damage; refer to the following chart:
3. If the concern is not visually evident, determine the symptom. GO to Symptom Chart .
Symptom Chart SECTION 307-
05: Automatic Transaxle/Transmission External Controls 2003 Mustang Workshop Manual Special Tool(s)
73 Digital Multimeter
105-
R0051 or equivalent
Visual Inspection Chart Mechanical Electrical
z
Shift control linkage binding.
z Shift lock actuator.
z Shift control cable.
z Interlock cable. z
Circuitry.
z Central junction box (CJB) fuse:
„17 (15A)
„ 28 (15A)
„ 35 (15A)
z Brake pedal position (BPP) switch.
z Wiring harness.
z Loose or corroded connections.
z Bulb.
SYMPTOM CHART Condition
Possible Sources Action
z The shift interlock
system does not
release/lock correctly z
Circuitry.
z CJB Fuse 17 (15A)
or Fuse 35 (15A).
z Shift lock actuator.
z Brake pedal position
(BPP) switch. z
Go To Pinpoint Test A . Klj . 1 ba
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DIAGNOSIS AND TESTING
Speed Control
Refer to Wiring Diagrams Cell
31 , Speed Control for schematic and connector information.
Principles of Operation
The speed control system is designed to maintain vehicle speed above 48 km/h (30 mph). After the
ON switch is depressed, depressing the SET/ACCEL switch will activate the speed control servo. To
increase a set speed, either depress and hold for continuous acceleration, or momentarily tap the
SET/ACCEL switch for 1.6 km/h (1 mph) acceleration increments. To decrease a set speed, depress
and hold the COAST switch until the target speed is reached, or momentarily tap the COAST switch
for 1.6 km/h (1 mph) deceleration increments. When the speed control system has been disabled by
tapping the brake pedal, the RESUME switch can be depressed and the vehicle will return to the
original set speed if the vehicle is traveling over 48 km/h (30 mph) and the OFF switch has not been
depressed.
NOTE: The deactivator switch is provided as an additional safety feature. Normally, when the brake
pedal is depressed, an electrical signal from the brake lamp circuit to the speed control servo will
deactivate the system. Under increased brake pedal effort, the deactivator switch will open and
remove power to the speed control servo, releasing the throttle independent of the speed control
servo.
NOTE: The air bag sliding contract provides the electrical interface between the steering column wiring
and the speed control actuator switches in the steering wheel.
The inputs to the speed control servo are the:
zvehicle speed signal.
SECTION 310-
03: Speed Control 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent
diagnostic tool 73 Digital Multimeter or
equivalent
105-
R0051 Breakout Box, EEC-V Control
System 418-049, or equivalent
014- 00950 Klj . 1 ba
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z
speed control actuator switches.
z brake pedal position (BPP) switch.
z clutch pedal position (CPP) switch.
z deactivator switch.
The output of the speed control servo is the:
zspeed control actuator cable controlling the throttle position.
Inspection and Verification
NOTE: If any concerns are noted with the speedometer, stoplamps, or horn, address those concerns
by referring to their associated sections before continuing speed control diagnosis.
1. Verify the customer concern by operating the speed control system.
2. Visually inspect for obvious signs of mechanical and electrical damage.
3. If the fault is not visually evident, verify the symptom and GO to the Symptom chart.
Symptom Chart
NOTE: New speed control diagnostic software is available in Version 12 or higher for the diagnostic
tool. When using this software, it is necessary to use Next Generation Speed Control Adapter 007-
00586 with the diagnostic tool.
NOTE: Refer to the Wiring Diagrams for connector numbers stated in the Pinpoint Test.
Visual Inspection Chart Mechanical Electrical
z
Deactivator switch
z Speed control actuator cable not attached to throttle
z Speed control actuator cable not fully seated to the
engine bracket z
Central junction box (CJB)
Fuse:
„15 (15A)
„ 33 (15A)
„ 35 (15A)
z Battery junction box (BJB)
fuse:
„HORN (20A)
z Wiring harness
z Loose or corroded
connections
z Speed control actuator
switches
Symptom Chart Condition
Possible Sources Action
z The speed control is zCentral junction zGo To Pinpoint Test A . Klj . 2 ba
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DIAGNOSIS AND TESTING
Climate Control System
Refer to Wiring Diagrams Cell
54 , Air Conditioner/Heater for schematic and connector information.
SECTION 412-
00: Climate Control System - General Information 2003 Mustang Workshop Manual Special Tool(s)
Connector, Refrigerant
Pressure Line
412-
093 (T94P-19623- E) Set, A/C Fittings
412-
DS028 (014- 00333, D93L-
19703- B) or equivalent Vacuum Pump Kit
416-
D002 (D95L-7559- A) or
equivalent Breakout Box, EEC-V Control
System
418- 049 (014-00950, T94L-50-
EEC- V) Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent
diagnostic tool Pressure Test Kit
014-
R1072 or equivalent 77 III Automotive Meter
105-
R0056 or equivalent Klj . 1 ba
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z
Does the vacuum drop? system for normal
operation.
No
REPAIR or INSTALL a
new function selector
switch. TEST the
system for normal
operation.
A13 REVIEW THE VEHICLE'S HISTORY
z
Key in OFF position.
z Review the vehicles history.
z Did the climate control system function correctly prior to
this concern? Yes
GO to
A16 .
No
GO to A14 .
A14 CHECK THE VACUUM HOSES TO DAMPER DOORS
z
Connect a vacuum pump to each hose and try to pull a vacuum.
If the vacuum pump can pull a vacuum, the hose is plugged. If
the vacuum pump pulls a partial vacuum, the hose is restricted.
z Is a hose plugged or restricted? Yes
INSTALL a new
vacuum hose. TEST
the system for normal
operation.
No
GO to
A15 .
A15 CHECK THE VACUUM HARNESS
z
Compare the vacuum hose color in each vacuum harness to the
vacuum diagram.
z Does the hose color agree with the schematics? Yes
GO to
A16 .
No
INSTALL a new
vacuum harness. TEST
the system for normal
operation. A16 CHECK A/C VACUUM CIRCUIT
z
Check the A/C vacuum circuit for pinched or kinked vacuum
hose. Yes
REPAIR or INSTALL a
new vacuum hose.
TEST the system for
normal operation.
No
GO to
A17 . Klj . 12 ba
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DIAGNOSIS AND TESTING
Instrument Cluster and Panel Illumination
Refer to Wiring Diagrams Cell
71 , Instrument Illumination for schematic and connector information.
Inspection and Verification
NOTE: A new instrument cluster must be reconfigured. Refer to Section 418 - 01 .
NOTE: The instrument panel dimmer switch is a part of the headlamp switch.
1. Verify the customer concern.
2. Visually inspect for obvious signs of electrical damage.
3. If the fault is not visually evident, determine the symptom and proceed to the Symptom Chart.
Symptom Chart SECTION 413-
00: Instrument Cluster and Panel Illumination 2003 Mustang Workshop Manual Special Tool(s)
73III Automotive Meter
105-
R0057 or equivalent
Visual Inspection Chart Electrical
z
Central junction box (CJB) fuses:
„5 (15A)
„ 21 (5A)
„ 34 (20A)
„ 37 (5A)
„ 32 (15A)
„ 27 (20A)
z Circuitry
z Damaged switch
Symptom Chart Condition
Possible Sources Action
z The control illumination is
inoperative z
Central junction box
(CJB) fuse 37 (5A).
z Circuitry.
z Headlamp switch. z
Go To Pinpoint Test A .
z The instrument cluster
illumination is inoperative z
Circuitry.
z Instrument cluster. z
Go To Pinpoint Test B . Klj . 1 ba
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Pinpoint Tests
PINPOINT TEST A: THE CONTROL ILLUMINATION IS INOPERATIVE
PINPOINT TEST B: THE INSTRUMENT CLUSTER ILLUMINATION IS
INOPERATIVE z
Bulb(s).
z The climate control
illumination is inoperative z
Circuitry.
z Bulb(s). z
Go To Pinpoint Test C .
z The audio system
illumination is inoperative z
Circuitry.
z Audio unit. z
Go To Pinpoint Test D .
z A single illumination source
is inoperative z
Circuitry.
z Switch. z
Go To Pinpoint Test E .
Test Step Result / Action to Take
A1 CHECK PARKING LAMPS
z
Place the headlamp switch in the ON
position.
z Are the exterior lamps on? Yes
Place the headlamp switch in the OFF position.
GO to
A2 .
No
REFER to Section 417 - 01 .
A2 CHECK HEADLAMP SWITCH
z
Key in OFF position.
z Carry out the headlamp switch
components test;
Refer to Wiring Diagrams Cell 149 for
schematic and connector information.
.
z Is the headlamp switch OK? Yes
RECONNECT the headlamp switch. GO to
A3 .
No
INSTALL a new headlamp switch. REFER to
Section 417 - 01 . TEST the system for normal
operation. A3 CHECK CIRCUIT 1045 (DB/WH)
z
Place the headlamp switch in the ON
position.
z Rotate the instrument panel dimmer
switch to the full illumination position.
z Measure voltage between central
junction box (CJB) fuse 37 (5A) and
ground.
z Is the voltage greater than 10 volts? Yes
REPAIR circuit 19 (LB/RD). TEST the system for
normal operation.
No
REPAIR circuit 1045 (DB/WH). TEST the system
for normal operation.
Test Step Result / Action to Take
B1 CHECK VOLTAGE TO INSTRUMENT CLUSTER
ILLUMINATION z
Disconnect: Instrument Cluster .
z Place the headlamp switch in the ON position.
z Rotate the instrument panel dimmer switch to the full Yes
GO to
B2 . Klj . 2 ba
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