
Ignition
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7.3.2 Sensors and input information
A typical early ESA system is shown as Figure 7.16. In order for the ECU
to calculate suitable timing and dwell outputs, certain input information is
required.
Figure 7.16 Programmed ignition systems
Figure 7.17 Position of a programmed
ignition crankshaft sensor
Engine speed and position – crankshaft sensor
This sensor is a reluctance sensor positioned as shown in Figure 7.17. The
device consists of a permanent magnet, a winding and a soft iron core. It
is mounted in proximity to a reluctor disc. The disc has 34 teeth, spaced at
10° intervals around the periphery of the disc. It has two teeth missing, ...