I had this same problem. I also got new batteries, but to no avail. The Battery would not charge even though the light lit up indicating that the operation was going. Finally I charged MY battery in my wife's LD and transferred it back to mine fully charged and it worked for a day, but when it ran down I had the identical problem again. I guessed that the ribbon cable was mucked up or the charging protocol was screwed up on the main board. I purchased a plug module/cable assembly from one of the parts sources. This includes the cradle plug, the headphone jack, the hot keys, and all kinds of other stuff, plus the ribbon cable which runs about two or three inches and plugs into the Mother Board.
This replacement operation is pretty nasty, and requires detail work and patience. It must have taken me two hours, and the headphone jack was a micron out of position and refused to plug in when the assembly was done. Little bastard.
The new assembly worked though. Then I tried to "fix" the defective one. That did _not_ work. Those ribbons are nasty little critters when they fail.
Where the fail point is and why it fails, I have no idea.

Phil

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