Hard Shutdown (two back to back obstructions) LED blinking, Buzzer sounds for 5 minutes 936 control board February 14, 2020 22:46 Updated Clear any obstructions from the path of the gate. Press RESET to clear (or hard reset button). Related articles How do I Replace my 816 Actuator's Encoder(Smart Sensor) Emerson Commander SK Variable Frequency Drive- Hardware Fault Codes (HF) Nice | HySecurity Product Spotlight Brochure How do I get my 816 extension tube back to factory position? Fault 4, Gate no load, Smart DC operators