OPERATION
OPERATION
3.7L V-6
The Camshaft Position Sensor (CMP) sensor (3) on
the 3.7L V-6 engine contains a hall effect device
referred to as a sync signal generator. A rotating target
wheel (tonewheel) for the CMP is located at the front
of the camshaft for the right cylinder head. This sync
signal generator detects notches (1) located on a
tonewheel. As the tonewheel rotates, the notches pass
through the sync signal generator. The signal from the
CMP sensor is used in conjunction with the Crankshaft
Position Sensor (CKP) to differentiate between fuel
injection and spark events. It is also used to synchro-
nize the fuel injectors with their respective cylinders.
When the leading edge of the tonewheel notch enters
the tip of the CMP, the interruption of magnetic field
causes the voltage to switch high, resulting in a sync
signal of approximately 5 volts.
When the trailing edge of the tonewheel notch leaves
then tip of the CMP, the change of the magnetic field
causes the sync signal voltage to switch low to 0
volts.
4.7L V-8
The CMP sensor (3) on the 4.7L engine contains a
hall effect device called a sync signal generator to
generate a fuel sync signal. This sync signal generator
detects notches (1) located on a tonewheel. The tone-
wheel is located at the front of the camshaft for the
right cylinder head. As the tonewheel rotates, the
notches pass through the sync signal generator. The
pattern of the notches (viewed counter-clockwise from
front of engine) is: 1 notch, 2 notches, 3 notches, 3
notches, 2 notches 1 notch, 3 notches and 1 notch.
The signal from the CMP sensor is used in conjunc-
tion with the crankshaft position sensor to differentiate
between fuel injection and spark events. It is also
used to synchronize the fuel injectors with their
respective cylinders.
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IGNITION CONTROL - SERVICE INFORMATION
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