MGL Avionics User Forum

I installed the V16 radio and temporarily hooked up everything to a 12V battery. Eventually everything worked perfectly, transmitting and receiving etc. Very happy.

I had to change the battery for another reason and when hooking it up, I may have accidentally hooked positive to negative for a second. Since then, only the control head comes to life and I get the message "com not detected". The green LED on the radio is not coming on. Could this have caused something serious? Is there any kind of protection built into the radio?

Yes it has protection. Open the radio and you will likely see a small component (black in color) that is burned. There are a number of these on the board, most of them installed on ground lines to the connector. They are small ferrites we tend to use for both RF noise suppression as well as their nature to act as a fuse. If you see one that is blown - that's where the big current was flowing.
If you are handy with a soldering iron you can remove it and replace with a small piece of wire. That should get it working again. Bit of course for the future that particular pin has no more over current protection.