Nuvi 500 firmware bug

[Dickfoster]

I have found that when a 24K topo is loaded and the unit is navigating to a destination and the unit is on the car charger the map display will freeze up. It's as if the unit is lost in some battery management loop or something and can't find the time to update the map display. It does however keep track of were it is etc is just the map display that ceases to be updated. It seems the only way to get it unfrozen is to remove the cigarette lighter plug then power cycle the unit. Just trying to turn it off and back on with the power button is not sufficient, you have to break into the battery charge routine. Only then can you get it to restart. However when you do the restart, the route and destination you were navigating to are retained and the unit picks up from the current location and continues normally. 

Nuvi 500 with a single state topo loaded from 8GB micro SD that was created from a Garmin DVD. Latest software etc. loaded in the unit. I have had it hang up with both CA and AZ topos so far so it looks like the Nuvi firmware that is harboring the bug. The latest 50states+ 100K topo and street maps data were loaded and enabled at the time too.

[Seldom]

If I understand you correctly, none of the problem maps were obtained from this site?  If so, sounds like a problem for Garmin, although you may want to make sure the card is well seated.  I've had problems with my OR300 when the card wasn't seated properly, but I suspect the Nuvi has a different card mount.

[Dickfoster]

I belive it to be a firmware bug so it would be regarless of the topo data source. There is no other indication of any connection issues with the memory card. Having spent my life in the electronics industry as both technican and engineer, I have developed a pretty good nose for this sort of thing.

I have also let Garmin know about it but the purpose here was to alert other users of both the problem as well as the workaround.   

If I understand you correctly, none of the problem maps were obtained from this site?  If so, sounds like a problem for Garmin, although you may want to make sure the card is well seated.  I've had problems with my OR300 when the card wasn't seated properly, but I suspect the Nuvi has a different card mount.