Precis L4-1468cc 1.5L SOHC (1993)
luminous diodes pass through the slits to the photo sensing diodes. When the photo diodes receive the light, they become conductive and generate
a signal, which is sent to the Control Unit.
Photoelectric Signal Pattern
CAMSHAFT (TDC) SIGNAL:
Top dead center is detected by the signal obtained through the one inner slit of the disc. The ECU, based upon this signal, determines which of the
four pulses from the crank angle sensor is the signal for the #1 cylinder.
CRANKSHAFT POSITION SIGNAL:
The four slits located at the outer circumference of the disc serve to detect the position of the crankshaft (and, therefore, the piston) relative to top
dead center. The ECU, based on this signal, determines the fuel injection timing, and also calculates the amount of intake-air, the timing of the
ignition signal, etc. for each revolution of the engine.
