I had a similar problem with one of my N800's. Mine was self induced though by having the polarity wrong on a generic charger and plugging my N800 into it. Quoting GreyGhost from another forum "Electronics run on smoke, if the smoke gets out it stops working"

On my N800 this caused a small surface mount fuse to go bad. I ordered a replacement fuse and have it at home but have not replaced it yet to see if this was the only damaged part.

Not sure if if the cause of your problem is the same as mine but the symptons are the same.

These are very very tiny components and unless you have experience with soldering these small Surface Mount Components I would have some else do it. I have the schematic on my home PC and can get more info tonight if you need it.
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