2003 FORD MUSTANG sensor

18. Disconnect the electrical connector.
19. Disconnect the following generator electrical connectors:
zBattery power supply wire.
z Voltage regulator.
20. Disconnect the camshaft position (CMP) sensor electrical connector.
21. Disconnect the engine coolant temperature (ECT) sensor electrical connector. Klj . 5 ba
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22. Remove the wiring harness.
zSeparate the wiring harness from the LH valve cover stud bolt.
z Separate the wiring harness from the power steering reservoir bracket.
Installation 1. Position the wiring harness: zInstall the wiring harness retainer onto the LH valve cover stud bolt.
z Install the wiring harness retainer into the power steering reservoir.
2. Connect the ECT sensor electrical connector.
3. Connect the CMP sensor electrical connector. Klj . 6 ba
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REMOVAL AND INSTALLATION
Supply Manifold
Removal
WARNING: Do not smoke or carry lighted tobacco or open flame of any type when
working on or near any fuel related components. Highly flammable mixtures are always present
and can ignite. Failure to follow these instructions can result in personal injury.
WARNING: Fuel in the fuel system remains under high pressure even when the engine is
not running. Before working on or disconnecting any of the fuel lines or fuel system
components, the fuel system pressure must be relieved. Failure to follow these instructions
can result in personal injury.
1. Disconnect the battery ground cable. For additional information, refer to Section 414 - 01 .
2. Remove the upper intake manifold. For additional information, refer to Section 303 - 01D .
3. Relieve the fuel pressure. For additional information, refer to Section 310 - 00 .
4. Disconnect the fuel line. For additional information, refer to Section 310 - 00 .
5. Position the wiring harness aside. zDisconnect the RH fuel injector electrical connectors.
z Separate the harness from the RH fuel supply manifold stud bolt.
6. Disconnect the fuel pressure sensor. zDisconnect the electrical connector.
z Disconnect the vacuum hose.
SECTION 303-
04D: Fuel Charging and Controls — Mach I 4.6L (4V) 2003 Mustang Workshop Manual Klj . 1 ba
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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
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Symptom Chart
Pinpoint Tests
PINPOINT TEST A: THE ENGINE DOES NOT CRANK AND THE
RELAY DOES CLICK
SYMPTOM CHART Condition
Possible Sources Action
z The engine does
not crank and the
relay does click z
Battery.
z Fuse.
z Starter
motor/solenoid.
z Ignition switch.
z Circuit. z
Go To Pinpoint Test A .
z The engine does
not crank and the
relay does not
click z
Fuse.
z Battery.
z Starter relay.
z Ignition switch.
z Digital transmission
range (TR) sensor.
z Starter solenoid.
z Clutch pedal
position (CPP)
switch.
z Circuit. z
Go To Pinpoint Test B .
z The engine
cranks slowly z
Battery.
z Starter
motor/solenoid.
z Circuit. z
Go To Pinpoint Test C .
z Unusual starter
noise z
Starter motor
mounting.
z Starter motor.
z Incorrect starter
drive engagement. z
Go To Pinpoint Test D .
z The starter spins
but the engine
does not crank z
Starter Motor zINSPECT the starter motor
mounting and engagement.
REPAIR as necessary.
z Damaged
flywheel/ring gear
teeth. z
INSPECT the flywheel/ring
gear for damaged, missing or
worn teeth. REPAIR as
necessary. Test Step Result / Action to Take
A1 CHECK THE VOLTAGE TO THE STARTER RELAY
z
Measure the voltage between the starter relay pin 30,
circuit 1050 (LG/VT) and ground. Yes
GO to
A2 .
No
REPAIR circuit 1050 (LG/VT) Klj . 2 ba
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PINPOINT TEST B: THE ENGINE DOES NOT CRANK AND THE
RELAY DOES NOT CLICK
Test Step Result / Action to Take
B1 CHECK CIRCUIT 33 (WH/PK) FOR VOLTAGE
z
Disconnect: Starter Motor Relay.
z Key in START position.
z Measure the voltage between the starter motor relay pin 85,
circuit 33 (WH/PK) and ground while holding the key in the
START position.
z Is the voltage greater than 10 volts? Yes
GO to
B10 .
No
For automatic
transmissions, GO to
B2 . For manual
transmissions, GO to
B5 .
B2 CHECK CIRCUIT 32 (RD/LB) FOR VOLTAGE AT THE DIGITAL
TR SENSOR z
Key in OFF position.
z Disconnect: Digital TR Sensor C110.
z Key in START position.
z Measure the voltage between the digital TR sensor C110 pin
10, 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
B3 .
No
GO to B7 .
B3 CHECK CIRCUIT 33 (WH/PK) FOR OPEN
z
Key in OFF position.
z Measure the resistance between the digital TR sensor C110 pin Yes
GO to
B4 .
No
REPAIR circuit 33
(WH/PK). TEST the
system for normal
operation. Klj . 4 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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DESCRIPTION AND OPERATION
Engine Ignition
The ignition coil (12029), which is mounted on the upper intake manifold, can be described as a coil
pack containing three separate coil units. Each coil unit is individually controlled by the powertrain
control module (PCM) (12A650) through separate wire leads. Each coil unit activates two spark plugs
wired in a series by the spark plug wires (12286).
zOne spark plug activates on the compression stroke and uses the majority of the ignition coil's
stored energy.
z The other spark plug activates on the exhaust stroke and uses very little of the ignition coil's
stored energy.
z Because the pairs of spark plugs are connected in a series, one spark will travel from ground to
the electrode while the other spark will travel from the electrode to ground.
The spark plug (12405):
zchanges the high voltage pulse into a spark which ignites the fuel and air mixture.
z originally equipped on the vehicle has a platinum- enhanced active electrode for long life.
The crankshaft position (CKP) sensor (6C315):
NOTE: Initial engine ignition timing is set at 10 degrees ± 2 degrees before top dead center (BTDC)
and is not adjustable.
zis a variable reluctance sensor triggered by a 36- minus-1 tooth trigger pulse wheel located on
the crankshaft (6303) inside the engine front cover (6019).
The sine wave type signal generated from the crankshaft position sensor provides two types of
information:
zposition of the crankshaft in 10 degree increments
z the crankshaft speed (rpm)
The powertrain control module (PCM) (12A650) uses this information to determine ignition coil turn ON
and turn OFF times and misfire detection.
For additional information, refer to Section 303 - 14 .
SECTION 303-
07A: Engine Ignition — 3.8L 2003 Mustang Workshop Manual Klj . 1 ba
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