I had a working 4100nex and decided to install the recent firmware update. I used an sd card and everything seemed fine. The unit was reading the card at which time I stepped away for a moment. I returned to a blank radio which never turned back on. I had the key on all the time and didn't rush to try to restart vehicle when I suspected a problem.
Now I'm very sad with a dead radio. I thought about a blown fuse but unit was working before attempted firmware update.
Please help
Thanks. Brian