The Camshaft Position Sensor (CMPS) detects the compression TDC of the No. 1 cylinder. The CMPS is a hall type sensor and targets on the end of the camshaft. When the target triggers the sensor, in a running engine, the sensor voltage is 5V then goes to 0V. The CMPS signal is sent to the PCM and the PCM uses the CMPS signal for synchronizing the sequential fuel injectors.