My 840 v9.29 had 8% of battery so I plugged it to charger. It was in sleep mode. After this screen was enabled and Garmin logo showed. After a few hours display is still on with the same image and 840 do not react for anything. It is dead.
My 840 v9.29 had 8% of battery so I plugged it to charger. It was in sleep mode. After this screen was enabled and Garmin logo showed. After a few hours display is still on with the same image and 840 do not react for anything. It is dead.
If you haven't yet, you might try resetting it by holding the power button for 10 sec.
www8.garmin.com/.../GUID-46A06A7C-1F46-4DBA-B010-DAD7BA6BE59E.html
I had the same issue! My new Garmin 840 was attached to the Garmin Charge Power Pack and when I came back to it a few days later, the 840 looked like it was dead. Not responsive with any buttons.
I held the power button for 10+ seconds (I counted beyond 10) and it came back to life. Very helpful. Thank you!