Sonata V6-3.0L (1991)
Top Dead Center (TDC) Sensor: Description and Operation
Distributor Exploded View
Crank Angle And #1 TDC Sensor
The crankshaft angle sensor and the No.1 cylinder TDC sensor are composed of a disc and unit assembly. The disc is a metal disc which has six
light-transmission slits located 60° apart around its circumference. There is also an additional series of slits (1° per slit at 2° increments, with a 10° blank
space) located on the outer circumference of the disc. The inner slits are for the crankshaft angle sensor (individual cylinder timing referance marks). The
outer series of slits is to establish No.1 TDC.
The disc is affixed to the distributor shaft. When the shaft rotates, the slits in the disc are optically read by the unit assembly. The unit assembly, in order
to be able to detect the two types of slits, incorporates two luminous diodes and two photo diodes. There is a very slight clearance between the luminous
diodes and the photo diodes, and the disc rotates within this space.