Crankshaft Angle Sensor
The crank angle sensor is a basic signal sensor for the entire ECCS. It monitors engine speed and piston position, and it sends signals to the ECCS control unit for control of ignition timing.
The unit is built into the distributor, and has 2 diodes and a wave-forming circuit. When a signal rotor plate passes the space between light emitting diode (LED) and photo diode, the slit to the signal rotor plate alternately cuts the light which is sent to the photo diode from the LED. This causes a pulsating voltage which is converted into an on-off pulse by the wave-forming circuit and sent to the control unit.