No power plug works for me. At first my battery pack worked fine, but the AC adaptor worked flakey, then I replaced the tip of the AC adaptor and it worked for a while. Then it got flakey again, and so did the battery pack.
I opened it (sl-5500) up and looked at it closely, and it seems that the connector (pic here http://www.tekprosystems.com/zaurus/internals.htm ) is the problem. It has a silverish layer on the outside (shine a real bright light into it) that conducts good, but once the outer layer wears off, the internal layer is copper, which corrodes easy. The silverish layer isn't even covering everything, just where it connects. Take a look inside back/side of the black box of the power connector, and you will see the (possibly) corroded copper exposed.
No amount of cleaning has done anything. It apparently needs to be replaced. I would prefer a replacement that works like the original inside the unit, but if it hangs out with wires that is no big deal. I always have either the battery pack or ac adaptor connected anyway.
I will probably stop by radio shack and see what they say, but if anyone has any suggestions for where to get replacement parts it would be appreciated.
The main reason I am making this post though is that I read through the titles of every post in this section of the forum, and see nothing related to this. Hasn't this happened to anyone else yet? Have I misdisgnosed the problem?