I have a Liftmaster Elite model 3850 opener. It was installed about 7 months ago by a professional door company. Suddenly, the door has started opening (not closing) on its own. The LED light on the main unit is steady green. The company that installed it came out and wasn't especially helpful. The tech seemed skeptical that there was a problem at all. He replaced the wall control unit, but that has not solved the problem. I told the service tech that I saw a brief message on the LED readout that said something about miswiring. I only saw this message once and didn't see the entire message as it was scrolling across the screen. He didn't seem to be interested in that bit of information. I took the batteries out of the spare remote to be sure that wasn't causing a problem. Any ideas?