2003 FORD MUSTANG fuse

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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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
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2. Inspect to determine if one of the following mechanical or electrical concerns apply:
a A leak in the vacuum control circuit may occur during acceleration (slow leak), at all times
(large leak), or only when specific functions are selected (indicating a leak in that portion of the
circuit). The vacuum hoses used in the passenger compartment control circuit are constructed
from PVC plastic material. The vacuum hoses used in the engine compartment are constructed
of Hytrel® . Because of the materials used, never pinch the vacuum hoses off during diagnosis
to locate a leak. A wood golf tee can be used as a plug when it is necessary to plug one end of
a vacuum hose for leak test purposes.
3. If the inspection reveals obvious concerns that can be readily identified, repair as required.
4. If the concern remains after the inspection, connect the scan tool to the data link connector (DLC) located beneath the instrument panel and select the vehicle to be tested from the scan
tool menu. If the vehicle selection cannot be entered:
zcheck that the program card is correctly installed.
z check the connections to the vehicle.
z check the ignition switch position.
If the scan tool still does not allow the vehicle selection to be entered, refer to the scan tool manual. 5. Carry out the DATA LINK DIAGNOSTIC TEST using the scan tool. If the scan tool responds with:
zCKT 914, CKT 915 or CKT 70 = ALL MODULE NO RESPONSE/NOT EQUIPPED, go to
Communication System Diagnostics in Section 418 - 00 to diagnose network concern.
z If the powertrain control module (PCM) is not listed for a communication concern, turn
the A/C function selector switch to OFF and execute self- test diagnostics for the PCM.
6. If any PCM DTCs are retrieved, and are related to the concern, go to the Powertrain Control Module Diagnostic Trouble Code (DTC) Index to continue diagnostics.
7. If no DTCs related to the concern are retrieved, go to the Symptom Chart to continue diagnostics.
Symptom Chart Visual Inspection Chart Mechanical Electrical
z
Loose, missing or damaged A/C compressor
drive belt.
z Loose or disconnected A/C clutch.
z Loose, misrouted or damaged vacuum lines. a
z Broken or leaking refrigerant lines.
z Broken or leaking vacuum control motor. z
Open fuses.
z Blower motor inoperative.
z A/C compressor inoperative.
z Circuitry open/shorted.
z Disconnected electrical
connectors.
Powertrain Control Module Diagnostic Trouble Code (DTC) Index DTC Description Action
P1460 WOT A/C cutout circuit
malfunction Refer to the Powertrain Control/Emissions Diagnosis
(PC/ED) manual.
P1464 A/C demand out of self-
test
range GO to DTC P1464. Klj . 5 ba
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Symptom Chart
Condition
Possible Sources Action
z Incorrect/erratic direction
of airflow from outlet(s) z
No vacuum to A/C heater
function switch selector.
z A/C heater function selector
switch leaks vacuum.
z Kinked/pinched vacuum hose.
z Leaking vacuum control
motor.
z Leaking A/C vacuum check
valve.
z Leaking A/C vacuum reservoir
tank and bracket.
z Vacuum actuator arm not
connected to door crank. z
Go To Pinpoint
Test A .
z Insufficient, erratic, or no
heat z
Low engine coolant level.
z Thermostat stuck open.
z Disengaged/damaged
temperature cable. z
Go To Pinpoint
Test B .
z The A/C does not
operate/does not operate
correctly z
CASS strategy failure.
z Open fuses.
z A/C clutch relay.
z Shorted blend door actuator.
z Powertrain control module.
z Circuitry short/open.
z A/C cycling switch damaged.
z A/C system discharged/low
charge.
z Function selector switch
damaged.
z A/C pressure cut-off switch
damaged.
z A/C compressor clutch
damaged. z
Go To Pinpoint
Test C .
z The A/C is always on zCircuitry short/open.
z A/C cycling switch.
z A/C heater function selector
switch.
z Constant control relay
module.
z Incorrect A/C clutch air gap. z
Go To Pinpoint
Test D .
z Insufficient A/C cooling zRestricted A/C evaporator
core orifice.
z Low refrigerant level. z
Go To Pinpoint
Test E .
z No operation in all the
temperature settings z
Damaged blend door actuator
cable.
z Damaged air temperature
control door. z
Go To Pinpoint
Test F .
z The blower motor does
not operate z
Open fuse.
z Circuitry open/shorted.
z Damaged heater blower
motor switch (18578).
z Damaged heater blower
motor switch resistor (18591).
z Damaged blower motor relay.
z Damaged blower motor. z
Go To Pinpoint
Test G .
z The blower motor
operates continuously in z
Circuitry short/open.
z Damaged heater blower z
Go To Pinpoint Klj . 6 ba
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z
Is the resistance reading less than 10,000 ohms? C13 CHECK CIRCUIT 198 (DG/OG) FOR A SHORT TO
GROUND z
Connect: A/C Pressure Cut- off Switch C1078.
z Measure the resistance between PCM C175- 41, circuit
198 (DG/OG), harness side and ground.
z Is the resistance less than 10,000 ohms? Yes
GO to
C15 .
No
INSTALL a new A/C fuse (15A).
TEST the system for normal
operation. If the fuse opens,
install a new PCM. REFER to
the Powertrain
Control/Emissions Diagnosis
(PC/ED) manual. C14 CHECK THE A/C PRESSURE CUT-
OFF SWITCH z
Disconnect: A/C Pressure Cut-off Switch C1078.
z Measure the resistance between the Rotunda EEC- V
Breakout Box pin 41, circuit 198 (DG/OG), and ground.
z Is the resistance less than 10,000 ohms? Yes
REPAIR circuit 198 (DG/OG)
for a short to ground. TEST the
system for normal operation.
No
INSTALL a new A/C pressure
cut-
off switch. REFER to
Section 412 - 03 .
C15 CHECK THE FUNCTION SELECTOR SWITCH
z
Key in OFF position.
z Connect: Function Selector Switch C294c.
z Disconnect: A/C Cycling Switch C130.
z Key in ON position.
z Turn the function selector switch to the A/C position.
z Measure the voltage between C130- 4, circuit 348 (VT),
harness side and ground. Yes
GO to
C17 .
No
GO to C16 . Klj . 19 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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The right and left turn indicators will illuminate when the steering column multifunction switch is in
either turn signal position or hazard lamps position by sending a battery signal to the instrument
cluster.
AIR BAG Warning Indicator
The AIR BAG warning indicator will be illuminated when the restraint control module (RCM) sends a
ground signal to the instrument cluster. The prove-
out of the AIR BAG warning indicator is controlled
by the RCM.
THEFT Indicator
The THEFT indicator provides a passive anti- theft system (PATS) prove-out. The THEFT indicator will
prove out for three seconds following the ignition switch cycle and will flash following an ignition switch
OFF transition to indicate that PATS is active.
Charging System Indicator
The charging system indicator will be illuminated when the generator provides a ground signal to the
instrument cluster. The instrument cluster provides a prove- out when the ignition switch is in the RUN
position with the engine off. When the engine is started, the generator removes the ground to the
instrument cluster and extinguishes the charging system indicator.
Overdrive Off (O/D OFF) Indicator
The O/D OFF indicator is controlled by the off/on message sent from the PCM over the SCP network.
The instrument cluster does not provide a prove- out for the O/D OFF indicator, but will remain
illuminated if the overdrive has been commanded off following the instrument cluster prove- out.
Traction Control Indicator
During initialization, the instrument cluster will receive the traction control system state status message
from the traction control module to determine if the vehicle is equipped with traction control. If the
vehicle is equipped with traction control, this information will be stored in random access memory
(RAM) and the indicator will prove out for three seconds during each ignition cycle. If this message is
not received, the instrument cluster will assume that the vehicle is not traction control equipped and
the indicator will remain off. When the traction control is active, the traction control module sends the
instrument cluster a traction control active signal and the instrument cluster illuminates the traction
control indicator. When the traction control is inactive, the traction control module removes the traction
control active signal and the instrument cluster turns off the indicator.
In the event of a traction control failure, the traction control indicator will remain off and the ABS
indicator will illuminate.
Inspection and Verification 1. Verify the customer concern.
2. Visually inspect for obvious signs of mechanical and electrical damage.
Visual Inspection Chart Mechanical Electrical
z
Fuel tank z
Central junction box (CJB) fuse(s): Klj . 4 ba
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