I have an out of warranty B5 that works and connects to the AP just fine, but if rebooted it will not boot again, it flashes red and will not even broadcast the wireless recovery. If we let it sit for a while ( in my case a few days) I can go back and recover it, unlock it, flash it, etc… It will stay connected and pass traffic without a problem. If I disconnect power after running it a few days, it goes back to a flashing red.
The issue started with it not accepting a remote firmware upgrade so we went on site to do it. It still would not accept the upgrade so we rebooted it and it never came back. Luckily we purchased a spare which was only a few hours away
I am thinking about opening it up to see if it has any swelled capacitors. Has anyone else encountered this?