17
Group 23 EDC III
Design and operation
Unit injectors (20)
The unit injectors are located under the valve cover,
mounted in the cylinder head.
The engine’s fuel need is analyzed up to 100 times
per second (depending on engine speed). The quantity
and timing of fuel injection into the engine are control-
led completely electronically via the unit injectors’
electromagnetically operated fuel valves. This means
that the engine always receives the correct amount of
fuel under all operating conditions, providing benefits
including improved fuel economy and minimized ex-
haust emissions.
Generator (8)
The belt-driven generator is located on the left-hand
front edge of the engine.
The voltage regulator of the generator is equipped with
a sensor system. The sensor system compares the
charging voltage between the generator connections,
B+ and B-, with the actual voltage between the positi-
ve and negative poles of the batteries. The voltage re-
gulator then compensates for any voltage drop in the
lines between the generator and the battery by increa-
sing the charging voltage from the generator as
needed.
Starter motor (16)
The starter motor is mounted on the flywheel housing
on the right-hand side of the engine.
When the motor is cut in, a gear on the armature shaft
of the starter motor is moved along the axis so that it
meshes with the gear ring of the engine’s flywheel.
The actuator solenoid of the starter motor controls
both the axial movement of the gear and connection
of the starter motor.
In turn, the actuator solenoid of the starter motor is
cut in via the start relay, which is activated when the
ignition key is turned to position III or the start button
is depressed.
The starter motor relay (
1
) is mounted next to the star-
ter motor solenoid.
1
