Be sure to observe the safety precautions described in this manual and the contents of the Hey guys, I have a Mazak QT250HP, and I am getting alarm 221 Turret Clamp Sensor Malfunction). The ‘Tool Open’ sensor (often S2) not reading correctly can cause this. Circuit Low Voltage P0136 O2 sensor (block 1, Sensor 2) C-025. Mazak alarm 252 deceleration sensor malfunction 4, mV IDE03275,Exh.