Test G FORD MUSTANG 2003 Workshop Manual

DIAGNOSIS AND TESTING
Fuel System
Refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
SECTION 310-
00: Fuel System — General Information 2003 Mustang Workshop Manual Klj . 1 ba
12003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

DIAGNOSIS AND TESTING
Fuel Tank And Lines
Refer to the Powertrain Control/Emissions Diagnosis (PC/ED) manual.
SECTION 310-
01: Fuel Tank and Lines 2003 Mustang Workshop Manual Klj . 1 ba
12003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

DIAGNOSIS AND TESTING
Acceleration Control
Inspection and Verification
1. Verify the customer's concern by operating the acceleration control system to duplicate the condition.
2. Inspect to determine if any of the following mechanical concerns apply:
3. If the inspection reveals an obvious concern that can be readily identified, repair as required.
4. If the concern remains after the inspection, determine the symptom(s) and GO to Symptom Chart .
Symptom Chart SECTION 310-
02: Acceleration Control 2003 Mustang Workshop Manual Visual Inspection Chart
Mechanical
z
damaged accelerator pedal and shaft
z damaged linkage
z damaged accelerator cable
z high engine idle speed
z damaged throttle body
Symptom Chart Condition
Possible Sources Action
z Excessive effort
needed to
depress
accelerator pedal
and shaft z
Worn
accelerator lever
pivot bushing. z
INSTALL a new accelerator
pedal and shaft.
z Accelerator
cable binding. z
INSTALL a new accelerator
cable.
z Worn or
damaged
throttle body. z
INSTALL a new throttle body.
REFER to Section 303 - 04A or
Section 303 - 04B .
z Accelerator pedal
and shaft feels
rough or raspy z
Frayed or
binding
accelerator
cable. z
INSTALL a new accelerator
cable.
z Worn or
damaged
throttle body. z
INSTALL a new throttle body.
REFER to Section 303 - 04A or
Section 303 - 04B .
z Accelerator pedal
and shaft binds or
sticks z
Kinked
accelerator
cable. z
INSTALL a new accelerator
cable. Klj . 1 ba
22003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

z
Foreign object
caught in
accelerator
pedal linkage. z
CHECK the accelerator pedal
linkage.
z Worn or
damaged
throttle body. z
INSTALL a new throttle body.
REFER to Section 303 - 04A or
Section 303 - 04B .
z High engine idle
speed z
Kinked
accelerator
cable. z
INSTALL a new accelerator
cable.
z Foreign object
caught in
accelerator
pedal linkage. z
CHECK the accelerator pedal
linkage.
z Incorrect engine
idle speed. z
REFER to the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual for diagnosis
and testing of the idle control
system. Klj . 2 ba
22003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

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
132003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

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
132003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

inoperative
box (CJB) fuse
17 (15A), 33
(15A).
z Battery junction
box (BJB) fuse
HORN (20A).
z Circuitry.
z Deactivator
switch.
z Clutch pedal
position (CPP)
switch.
z Speed control
actuator switch.
z Speed control
servo.
z Powertrain
control module
(PCM).
z The set speed
fluctuates z
Circuitry.
z Speed control
servo.
z Powertrain
control module
(PCM). z
Go To Pinpoint Test B .
z Engine. zREFER to the Powertrain
Control/Emissions
Diagnosis (PC/ED)
manual.
z The speed control
does not disengage
when the brakes are
applied z
Central junction
box (CJB) fuse
33 (15A).
z Circuitry.
z Brake pedal
position (BPP)
switch.
z Speed control
servo. z
Go To Pinpoint Test C .
z The speed control
does not disengage
when the clutch is
applied z
Cluch pedal
position (CPP)
switch.
z Speed control
servo. z
Go To Pinpoint Test D .
z The speed control
switch is
inoperative— COAST z
Speed control
actuator switch.
z Speed control
servo. z
Go To Pinpoint Test E .
z The speed control
switch is
inoperative—
SET/ACCEL z
Speed control
actuator switch.
z Speed control
servo. z
Go To Pinpoint Test F .
z The speed control
switch is
inoperative—
RESUME z
Speed control
actuator switch.
z Speed control
servo. z
Go To Pinpoint Test G .
z The speed control
switch is
inoperative— OFF z
Speed control
actuator switch.
z Speed control
servo. z
Go To Pinpoint Test H . Klj . 3 ba
132003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

Pinpoint Tests
PINPOINT TEST A: THE SPEED CONTROL IS INOPERATIVE
Test Step Result / Action to Take
A1 CHECK THE SPEED CONTROL SERVO VOLTAGE AND
GROUND z
Key in OFF position.
z Disconnect: Speed Control Servo C122.
z Key in ON position.
z Measure the voltage between speed control servo C122 Pin 7,
Circuit 294 (WH/LB), harness side and speed control servo
C122 Pin 10, Circuit 1205 (BK), harness side.
z Is voltage greater than 10 volts? Yes
GO to
A3 .
No
GO to A2 .
A2 CHECK THE CIRCUIT 1205 (BK) FOR AN OPEN
z
Key in OFF position.
z Measure the resistance between speed control servo C122 Pin
10, Circuit 1205 (BK), harness side and ground.
z Is the resistance less than 5 ohms? Yes
REPAIR Circuit 294
(WH/LB). TEST the
system for normal
operation.
No
REPAIR Circuit 1205
(BK). TEST the system
for normal operation.
A3 CHECK DEACTIVATOR SWITCH CIRCUITRY
z
Measure the voltage between speed control servo C122 Pin 9,
Circuit 636 (OG), harness side and speed control servo C122
Pin 10, Circuit 1205 (BK), harness side. Yes
GO to
A6 .
No
GO to A4 . Klj . 4 ba
132003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

z
Is the voltage greater than 10 volts? A4 CHECK CIRCUIT 10 (LG/RD) FOR AN OPEN
z
Disconnect: Deactivator Switch C2210.
z Measure the voltage between deactivator switch C2210 Pin 1,
Circuit 10 (LG/RD), harness side and ground.
z Is the voltage greater than 10 volts? Yes
GO to
A5 .
No
REPAIR the circuit.
TEST the system for
normal operation. A5 CHECK CIRCUIT 636 (OG) FOR AN OPEN
z
Measure the resistance between speed control servo C122 Pin
9, Circuit 636 (OG), harness side and deactivator switch C2210
Pin 2, Circuit 636 (OG), harness side.
z Is the resistance less than 5 ohms? Yes
INSTALL a new
deactivator switch;
REFER to
Switch —
Deactivator . TEST the
system for normal
operation.
No
REPAIR the circuit.
TEST the system for
normal operation. A6 CHECK THE SPEED CONTROL ACTUATOR SWITCH ON
CIRCUITRY z
Measure the voltage between speed control servo C122 Pin 5,
Circuit 151 (LB/BK), harness side and speed control servo C122
Pin 10, Circuit 1205 (BK), harness side, while the speed control
actuator switch ON is depressed. Yes
GO to
A9 .
No
GO to A7 . Klj . 5 ba
132003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...

z
Is the voltage greater than 10 volts? A7 CHECK CIRCUIT 151 (LB/BK) FOR AN OPEN
z
Disconnect: Air Bag Sliding Contact C218a.
z Measure the resistance between speed control servo C122 Pin
5, Circuit 151 (LB/BK), harness side and air bag sliding contact
C218a Pin 4, Circuit 151 (LB/BK), harness side.
z Is the resistance less than 5 ohms? Yes
GO to
A8 .
No
REPAIR the circuit.
TEST the system for
normal operation. A8 CHECK THE AIR BAG SLIDING CONTACT
z
Remove the air bag; REFER to Section 501 - 20B .
z Disconnect: Speed Control Actuator Switch.
z Measure the resistance between bottom of air bag sliding
contact Pin 1 (component side) and top of air bag sliding
contact Pin 3 (component side).
z Is the resistance less than 5 ohms? Yes
INSTALL a new speed
control actuator switch;
REFER to
Switch —
Speed Control
Actuator . TEST the
system for normal
operation.
No
INSTALL a new air bag
sliding contact; REFER
to Section 501 - 20B .
TEST the system for
normal operation. A9 CHECK THE SPEED CONTROL ACTUATOR SWITCH ON
CIRCUITRY FOR SHORT TO POWER z
Key in ON position.
z Measure the voltage between speed control servo C122 Pin 5,
Circuit 151 (LB/BK), harness side and speed control servo C122
Pin 10, Circuit 1205 (BK), harness side. Yes
GO to
A10 .
No
GO to A12 . Klj . 6 ba
132003 Mustang Workshop Manual
18. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_2308/S3B~us~en~ ...