Precis L4-1468cc 1.5L SOHC (1993)
Crankshaft Position Sensor: Description and Operation
Crankshaft Position and Camshaft (TDC) Sensors
Crank Angle And #1 TDC Sensor Location
SENSOR OPERATION
The Distributor houses the crankshaft position and camshaft (TDC) sensors. These sensors are incorporated into one unit, being a disc and a
pick-up unit. The disc is affixed to the main shaft and the light-transmitting unit is mounted stationary in the housing.
Crank Angle And #1 TDC Sensor
The crankshaft angle sensor and the Camshaft (TDC) sensor are composed of a disc and unit assembly. The disc is metal and has four
light-transmission slits located 90° apart around its circumference. There is also one additional slit located inward from these four. The inner slit is
for the Camshaft (TDC) sensor, and the outer slits are for the crankshaft position sensor
The pick-up unit assembly uses two luminous diodes and two photo diodes, in order to detect the two different slits. There is a very slight
clearance between the luminous diodes and the photo diodes, and the disc rotates within this space.
Crank Angle And #1 TDC Sensor System
As the main shaft rotates the slits at the discs edge pass between the light and the optical reading part of the unit. The light emitted from the
