GPS screen brightness

[Solent Ribman]

I have a Navman Trackfish 6600 and have problems seeing the screen. This weekend, for some reason, the screen seemed to have turned its brightness down so faint it was almost impossible for wife to give me readings. Not having manual with me, could not readjust brightness on water, as couldn't see the screen options!
The second problem is using polarised sunglasses, which not surprisingly requires one to turn head at awkward angles to see screen clearly. My questions are:
1. Is it possible the screen has gone dim by its own accord and if so, is this a sign of a possible problem with the unit?
2. How does one counteract the effect of polaroid sunglasses, other than not wearing them?

[donald463]

I have Navman 5500 and have to set to 'Sunlight colours' to see screen in any reasonably bright conditions.

[thomas]

1. My Garmin 555 was hopeless on Monday in the really bright sunshine, even on full brightness, I doubt very much the backlight has failed, RTFM and have to see if you can adjust it.

2. Wear non polarising sunnys or rotate the unit 90º

[Erin]

You'd have thought Navman would have polarised their screens in the same direction as sunglasses to avoid that problem. Garmin didn't miss that one! All you can do is check it's at full brightness.

[Solent Ribman]

Thanks for that, I'll look in the manual to see if same feature is on the 6600.

[jyasaki]

On the Lowrance units, hitting the power button briefly toggles between brightness settings. Don't know about Navman.

jky