Cylinder Identification Sensor: Description and Operation

TDC Sensor 1/2:

CKP Sensor:

TDC (Top Dead Center) 1/2 and CKP (Crankshaft Position) Sensors
The TDC 1 and TDC 2 sensors detect the position of the No.1 cylinder as a reference for sequential fuel injection to each cylinder. The CKP sensor detects engine speed and determines ignition timing and timing for fuel injection of each cylinder.