One problem led to another today.
I had high oil temps, and I wanted see if recycling my AF3500 in flight would have any effect on the oil temp readings. I pulled the breaker on the efis, and strangely my oil temp dropped 10 degrees. (putting the breaker back in caused the temps to go back up).
I still wanted to recycle the power on the EFIS, but pulling the breaker and/or turning off the avionics master switch just caused the EFIS to go on battery without the usual "I'm going to shutdown soon" messages that you get on the ground. (Now I see in the manual that auto-shutdown doesn't trigger when there's a/s or rpm, nice.)
I couldn't recall the exact pattern to reset by holding buttons 2+3+4 for 3 seconds. Instead, I was trying to hold down button 1 or button 1+2. Something I did resulted in the unit going into what looks like a continual rebooting sequence. I can't be sure of the exact operation that caused it, but the AF3500 went into a loop and would not come out. It continued on in this state for another hour+ of flight time. It did NOT stop even after landing and shut down. It was still doing the reboot sequence when I left the airport. Eventually the battery will be dead, and I'll see if it comes back to life. Dunno.
I have a video from my phone of this happening if that helps. Is this a known problem? While my actions triggered this, the device seemed to be in a completely unrecoverable state. My panel has suitable backups, so I was fortunate enough to be able to continue the flight to a safe landing.