2003 FORD MUSTANG jump start

DESCRIPTION AND OPERATION
Starting System
Starter Motor
The starter motor is a 12-
volt unit that has the starter solenoid mounted on the drive end housing and
functions as follows:
zThe current flows through the solenoid energizing coil until the solenoid plunger is at the end of
its travel.
z The plunger closes a set of contacts that bypass the energizing coil, letting the holding coil keep
the starter drive engaged and passing starting current to the starter motor.
z The motor is energized when the starter solenoid contacts are closed.
z The starter drive engages the flywheel ring gear and starts the engine.
z An overrunning clutch in the starter drive protects the starter motor from excessive speed when
the engine starts.
Starter Relay
The starter interrupt relay consists of:
zpull in coil and contacts
When the ignition switch is in the START position:
zthe pull- in coil is activated and pulls the contacts together.
z current passes through the starter relay from the engine compartment power distribution box to
the starter solenoid.
Clutch Pedal Position (CPP) Switch
The CPP switch for:
za manual transmission closes when the clutch pedal is depressed, completing the starting
circuit.
z an automatic transmission is a jumper inserted in place of the CPP switch to complete the
circuit.
Starter System — Operation
When the ignition switch is turned to the START position the starter relay switches power to the starter
solenoid causing the starter motor to engage as long as:
zthe clutch pedal is depressed (manual transmission only).
z the digital transmission range (TR) sensor is in PARK or NEUTRAL (automatic transmission
only).
SECTION 303-
06: Starting System 2003 Mustang Workshop Manual Klj . 1 ba
22003 Mustang Workshop Manual
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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
Is the voltage greater than 12.5 volts? for an open. TEST the
system for normal operation.
A2 CHECK THE VOLTAGE TO THE STARTER MOTOR
SOLENOID z
Measure the voltage between the starter motor solenoid
positive terminal and ground.
z Is the voltage 12.5 volts or greater? Yes
GO to
A3 .
No
REPAIR circuit 2037 (RD) for
an open. TEST the system
for normal operation. A3 MANUALLY JUMP THE STARTER MOTOR
z
Connect one end of a fused (15A) jumper wire to the
positive terminal of the battery and touch the other end to
the starter solenoid S- terminal.
z Does the starter solenoid engage? Yes
GO to
A4 .
No
INSTALL a new starter
motor. REFER to Starter Motor — 3.8L or
Starter Motor — 4.6L . TEST the
system for normal operation. A4 TEST THE STARTER MOTOR RELAY
z
Carry out the relay component test on the starter motor
relay. Refer to the relay component test in this section.
z Does the starter motor relay test good? Yes
REPAIR circuit 33
(WH/PK)/262 (BN/PK) for an
open. TEST the system for
normal operation.
No
INSTALL a new starter motor
relay. TEST the system for
normal operation. Klj . 3 ba
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12, circuit 33 (WH/PK) and the starter motor relay pin 86, circuit
33 (WH/PK).
z Is the resistance less than 5 ohms? B4 CHECK DIGITAL TRANSMISSION RANGE (TR) SENSOR
ADJUSTMENT z
Carry out the digital TR sensor adjustment. Refer to Section 307 - 01 .
z Is the digital TR sensor adjusted correctly? Yes
INSTALL a new digital
TR sensor. TEST the
system for normal
operation.
No
ADJUST the digital TR
as necessary. TEST the
system for normal
operation.
B5 CHECK CIRCUIT 32 (RD/LB) FOR VOLTAGE AT THE CLUTCH
SWITCH OR JUMPER z
Key in OFF position.
z Disconnect: Clutch Pedal Switch C255.
z Key in START position.
z Measure the voltage between the clutch pedal switch C255 pin
2, circuit 32 (RD/LB) and ground while holding the key in the
START position.
z Is the voltage greater than 10 volts? Yes
GO to
B6 .
No
GO to B7 .
B6 CHECK CIRCUIT 33 (WH/PK)/32 (RD/LB) FOR OPEN
z
Key in OFF position.
z Measure the resistance between the clutch pedal switch C255
pin 1, circuit 33 (WH/PK)/32 (RD/LB) and the starter motor relay
pin 86, circuit 33 (WH/PK)/32 (RD/LB).
z Is the resistance less than 5 ohms? Yes
INSTALL a new clutch
pedal switch. TEST the
system for normal
operation.
No
REPAIR circuit 33
(WH/PK)/32 (RD/LB).
TEST the system for
normal operation.
B7 CHECK FOR VOLTAGE AT FUSE 6
z
Key in OFF position.
z Disconnect: Fuse #6.
z Key in START position. Yes
REPAIR circuit 32
(RD/LB). TEST the Klj . 5 ba
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Component Tests
Starter Motor —Voltage Drop Test
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 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.
Always make the Digital Multimeter connections at the component terminal rather than at the wiring
end connector. Making a connection at the wiring end connector could result in false readings because
the meter will not pick up a high resistance between the wiring connector and the component.
Starter Motor— Motor Feed Circuit
1. Make sure the battery is fully charged. Perform a battery load test. For additional information, refer to Section 414 - 00 .
2. Disconnect the inertia fuel shut off (IFS) switch.
3. Connect a remote starter switch between the starter solenoid S- terminal and the battery positive
(+) terminal.
4. Connect the Digital Multimeter positive lead to the battery positive (+) post. Connect negative lead to the starter solenoid M- terminal. brackets for cracks.
z Check the starter motor mounting
bolts for looseness.
z Is the starter motor mounted
correctly? GO to
D2 .
No
REINSTALL the starter motor correctly. REFER to
Starter Motor — 3.8L or
Starter Motor — 4.6L in this
section. D2 INSPECT THE STARTER MOTOR
z
Remove the starter motor; refer to
Starter Motor — 3.8L or
Starter Motor — 4.6L in this section.
z Inspect the starter motor for
damage.
z Is the starter motor damaged? Yes
INSTALL a new starter motor. REFER to
Starter Motor — 3.8L or
Starter Motor — 4.6L in this section.
TEST the system for normal operation.
No
CHECK the starter drive. REFER to Component
Tests, Starter Drive Test in this section. INSTALL a
new starter motor. TEST the system for normal
operation. Klj . 8 ba
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PINPOINT TEST F: NO OPERATION IN ALL TEMPERATURE
SETTINGS
PINPOINT TEST G: THE BLOWER MOTOR DOES NOT
OPERATE/DOES NOT OPERATE CORRECTLY INSTALL a new A/C
compressor due to low
performance. REFER to
Section 412
- 03 . TEST the
system for normal operation. Test Step Result / Action to Take
F1 CHECK THE TEMPERATURE CONTROL
z
Start the engine and run at idle. Allow the engine to reach
normal operating temperature.
z Place the function selector switch in the NORMAL A/C
position.
z Adjust the temperature control to full warm position, and
physically feel the discharge air temperature at the at the
center panel vents.
z Rotate the temperature control to full cold position, and
physically feel the discharge air temperature at the center
panel vents.
z Does the discharge air temperature vary? Yes
The temperature blend
door is functioning
correctly. RETURN to the
symptom chart.
No
GO to
F2 .
F2 CHECK FOR A BROKEN A/C TEMPERATURE CONTROL
CABLE z
Remove the climate control assembly to gain access to the
control cable head.
z Move the temperature control from full warm to full cold.
z Inspect the cable control head as you move the temperature
control.
z Does the alignment mark on the control head move? Yes
INSTALL a new
evaporator housing.
REFER to
Section 412 -
02 .
No
INSTALL a new
temperature control cable
assembly. REFER to
Section 412 - 04 .
Test Step Result / Action to Take
G1 CHECK FOR VOLTAGE AT C238
z
Disconnect: Blower Motor Jumper C238.
z Key in ON position.
z Turn the blower motor selector to LOW.
z Turn the function selector to FLOOR.
z Check for voltage between C238- 6, circuit 249 (DB/LG) and
C238- 3, circuit 261 (OG/BK). Yes
GO to
G2 .
No
GO to G4 . Klj . 30 ba
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PINPOINT TEST G: THE GENERATOR IS NOISY REPAIR as
necessary. TEST the
system for normal
operation.
F2 CHECK FUSE
z
Key in START position.
z With the engine running, check battery junction box (BJB) fuse 20
(20A) in circuit 36 (YE/WH) for looseness by wiggling the fuse and
noting the charging system warning indicator lamp operation.
z Does the charging system warning indicator lamp flicker? Yes
REPAIR loose fuse
connections as
necessary. TEST the
system for normal
operation.
No
GO to
F3 .
F3 CHECK A CIRCUIT 36 (YE/WH) CONNECTIONS
z
Key in OFF position.
z Connect a fused jumper wire between the generator C102c, (4.6L
4V) or C102a (3.8L or 4.6L 2V) pin 3, circuit 36 (YE/WH), harness
side and the positive battery terminal.
z Key in START position.
z With the engine running, note the charging system warning
indicator operation.
z Does the charging system warning indicator lamp flicker? Yes
REFER to
Section 414 - 02 . TEST the
system for normal
operation.
No
REPAIR loose
connection(s) in
circuits. TEST the
system for normal
operation. Test Step Result / Action to Take
G1 CHECK FOR ACCESSORY DRIVE NOISE
z
Check the accessory drive belt for damage and
correct installation. Check the accessory
mounting brackets and generator pulley for
looseness or misalignment.
z Is the accessory drive OK? Yes
GO to
G2 .
No
REPAIR as necessary. REFER to
Section 303 - 05 for diagnosis and testing
of the accessory drive system. TEST the
system for normal operation. G2 CHECK GENERATOR MOUNTING
z
Check the generator mounting for loose bolts
or misalignment.
z Is the generator mounted correctly? Yes
GO to
G3 .
No
REPAIR as necessary. TEST the system
for normal operation. G3 CHECK GENERATOR FOR ELECTRICAL Klj . 9 ba
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8. If the draw is found to be excessive, pull fuses from the battery/central junction box one at a
time and note the current drop. Do not reinstall the fuses until you are finished testing.
9. Check the wiring schematic in the wiring diagram for any circuits that run from the battery without passing through the battery/central junction box. Disconnect these circuits if the draw is
still excessive.
Battery— Electronic Drains Which Shut Off When the Battery Cable is Disconnected
1. Repeat the steps of the battery drain testing.
2. Make sure all doors are closed and accessories are off. Without starting the engine, turn the ignition switch to RUN for a moment and then OFF. Wait a few minutes for the illuminated entry
lamps to turn off if equipped.
3. Connect the ammeter and read the amperage draw.
The current reading (current drain) should be less than 50 mA (0.05 amp). If the current drain exceeds
50 mA (0.05 amp) after a few minutes, and if this drain did not show in previous tests, the drain is most
likely caused by an inoperative electronic component. As in previous tests, remove the fuses from the
battery/central junction box one at a time to locate the problem circuit.
Generator On- Vehicle Tests
CAUTION: To prevent damage to the generator, do not make jumper wire connections
except as directed.
CAUTION: Do not allow any metal object to come in contact with the housing and the
internal diode cooling fins with key on or off. A short circuit will result and burn out the diodes.
NOTE: Battery posts and cable clamps must be clean and tight for accurate meter indications.
NOTE: Refer to the Battery Tester Procedure Manual for complete directions for testing the charging
system.
1. Turn off all lamps and electrical components.
2. Place the vehicle in transmission range NEUTRAL and apply the parking brake.
3. Carry out the Load Test and No- Load Test according to the following component tests:
Generator On- Vehicle Tests— Load Test
1. Switch the battery tester to the ammeter function.
2. Connect the positive and negative leads of the battery tester to the corresponding battery terminals.
3. Connect the current probe to the generator B+ output terminal, circuit 38 (BK/OG). Klj . 12 ba
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