produce the desired voltage in the secondary circuit at
high engine speeds.
CAPACITOR DISCHARGE IGNITION
The capacitor discharge (CD) ignition system is also
superior to the conventional ignition system. Like the
magnetic- pulse transistor ignition system, the CD
system has a special ignition coil, a transistorized pulse
amplifier, and a magnetic puke distributor. Unlike the
magnetic-pulse transistor ignition system, the CD
system has a high-voltage condenser connected across
the primary windings of the coil. The input to the coil is
constant and assures complete saturation of the coil
which results in the desired secondary voltage output at
high engine speeds.
ELECTRONIC IGNITION SYSTEM
Like the magnetic-pulse transistor ignition system,
Chryslers electronic ignition system is breakerless; that
is, there are no breaker points and there is no condenser.
(See fig. 4-31.)
The Chrysler electronic ignition system in
figure 4-32 consists of a battery, an ignition switch,
a dual ballast resistor, a special ignition coil, an
electronic control unit, and a special pulse-sending
Instead of the cam and rubbing block of the
conventional ignition system, the Chrysler electronic
system uses a magnetic pickup coil and a rotating
reluctor (fig. 4-33). As the teeth of the reluctor pass
the magnet of the pickup coil, a voltage pulse is
induced in the pickup coil which is a signal for the
module to interrupt the primary coil current. The
magnetic field in the ignition coil collapses and
induces a high voltage into The secondary winding
which fires the spark plugs.
Figure 4-32.-Electronic ignition system.
The electronic module is a solid-state device that
interrupts the primary coil current when signaled and
self-starts the primary current after a predetermined
time lapse. A compensating ballast resistor (0.5 ohms
typical) is used in series with the ignition coil and
battery circuit. The compensating ballast resistor
maintains a constant primary current with changes in
engine speed. During starting or cranking, the
compensating ballast resistor is bypassed, supplying
full-battery voltage to the ignition coil. The auxiliary
ballast resistor (5.0 ohms typical) limits the current to
the electronic module.
On this system, you adjust the air gap by aligning
one reluctor tooth with the pickup coil tooth. After
loosening the holding screw, use a nonmagnetic feeler
gauge of the correct size to obtain the proper air gap
between the reluctor and the pickup coil. Check the
setting for proper clearance at the reluctor tooth with a
nonmagnetic feeler gauge that is 0.002 inch larger than
the manufacturers specification.
Figure 4-31.-Electronic ignition distributor components.
Figure 4-33.-Electronic pickup and reluctor.