There is an active input tied into one of the open terminals of the Smart Touch or SMART DC Controller, such as OPEN or REMOTE RADIO OPEN, that is maintained and preventing the gate from closing. There will be a red LED illuminated next to one of these terminals to give an indication of which terminal is currently active. If the operator is solar powered, you will need to hold the show LED button at the bottom of the terminal strip to see any active LED. If there is a red LED next to the RADIO OPEN terminal with no wiring connected to the terminal, check the OPEN terminal in the RADIO OPTIONS section of the bottom of the Smart Touch or SMART DC Controller.