Hurray for forums. I had the same problem with my 2598 and the automatic time did the trick. I agree with Technowiz, why isn't it a default setting, because unticking it means the display doesn't work properly anymore.
Nothing is working! Auto or restore not helping Garmin
THIS ISN'T WORKING FOR ME! what do I do? Setting to auto, day, night, turning on/off the display timeout, setting timeout to all different minute settings, keeping clock on am/pm, restoring defaults, shut on and off, plugged or unplugged.
THE SCREEN GOES DARK with the voice staying normal, the screen goes to 20% automatically, I reset to 100, it goes dark a minute later. Nothing works. Started a few weeks ago, nothing changed on my end.
Not good for me. I had a 3597, never had this trouble, but the led failed. Bought a trade in from Garmin and sold it because it's not supported anymore. Bought a 2699 for its glass screen and 6". Everything is great, but the screen will randomly go to 20% brightness when I'm in and out of car thought day (I drive a lot). Spoke to Garmin numerous times and it's obviously a know issue. They had me do automatic time and reboot which works for a while. Then it's back to dimming. I always keep it plugged to 12v and it powers down every time I exit on its own. When it comes back on with car power it's a crap shoot if it will be dim or correct. I have to wait for harming to fix software or maybe someone found the trick?? Or I really need an exchange. Thanks
Darn, thought I'd found the solution, but it didn't work on my 2689. When I checked the settings, it was already on Automatic. Sounds like that may be the default now, but the problem is still showing up. Then again, this was a refurb unit, so maybe it was returned due to this problem.
Just changed mine to auto time and it has solved the issue here. Too annoying that the time is always off though but i'd rather that than a Lack screen
Where would we be without being "on the line"
For all the fellow frustrated Garmin users here I think I know where the problem truly lies. Garmin software folks try to be smart in backlit level and automatically dims it to like 25% when you enter a marked tunnel or underpass where the ambient light is very low. This works and helps to reduce glare to the driver. The problem is when you are just travelling past or over a marked tunnel and not actually inside, the device has no way of knowing and still dims the screen.
Unfortunately this is a case of being too clever for its own good. My old 255W never had this issue but my 3560 does. There is no hack to disable tunnel dimming as far as I have been searching. Hope this answer helps. Now can someone do a hack to disable this auto tunnel dimming?