I've now used my new radar unit twice with my 820. Both times the 820 froze. Yesterday the 820 froze two times, but I was able to shut it down and re-start with no loss of data as far as I can tell. Today the 820 froze (everything on the screen) once, and I could not re-start the unit. For example, two little circles indicating vehicles remained in place as well as all of the metrics. I tried turning the radar off, waited a few minutes and then back on. Nada. Then I just turned the radar off permanently, and a message appeared telling me I was disconnected from the radar. Amazing I was able to download the complete ride data when I got back home. Yes, I have the latest firmware. Can someone please suggest what I can try to do next besides call Tech Support? Very much appreciated.
Have the same problem---but it happens when I have Edge on Battery Sleep Mode, and just as it is about to go to sleep, a car approaches. Unit won't turn off, display is frozen, but I here the beeps of approaching cars. And on my last ride, the display finally went blank. But to my surprise, the Edge was still recording the entire ride. I've contacted Garmin support twice. They provide same fix both times, of resetting, etc. Haven't had a chance to use on a longish ride since last reset so don't know if this fix will work (it didn't work the first time....)
