My driveway gate controller is only opening on one side. The "master" gate side is not getting power from the circuit board. The "slave" side works normally. The "slave" LED (top right of front circuit board) lights up when the gate is operating, but the "master" LED does not light up. Power (~26vdc) goes to the two gate openers via the green blocks on the bottom left of the front circuit board. (There's a second circuit board behind the front board). When I switch the gate to open/close, I can measure 26 v coming from the "slave" green block but no power is coming from the "master" green block. All fuses are good. In case there was a short in the "master" gate motor, I disconnected all wires going from the "master" green block to the motor, but it made no difference. Nothing physical occurred to cause the problem; one morning, it just didn't work. I've posted a bunch of pics but I do understand it might be a bit difficult to get an idea of my setup. Included are pics of front and back of both circuit boards. Just in case one of you nice people has some time to look into this......maybe give me some idea of what I can look for or try? Thanks for any assistance!

 

I traced back the missing power from the left green block to a transistor that looks like it overheated, especially compared to similar transistors nearby. It's the transistor on the right, in this photo below. Could that be the problem?

 

I replaced the transistor and now it works! Hurray! Thanks for all the help.

 

Your welcome!

 

No sweat, judging by the two leads and size, it’s most likely a rectifier diode