DELL Latitude D600 Not Charging Battery

I have a Dell Latitude D600 that works fine with only the AC Adapter. It will not charge the battery and the charging LEDs flash 4 times orange and then once green.
In the power manager it has a red X over the battery symbol and stays at 0%. In the BIOS power manage it says battery status is "idle".
So the first thing I did was replace the the batery with a brand new identical battery.....I get the same thing.
After reading DELL forums and bulletins, it was recommended that I replace the DC jack on the MB...I get the same thing.

Also, when booting I get "The AC Power Adapter type cannot be determined. This will prevent optimal system performance."
So I try a known working/identical AC adapter.....same thing.

What's next?? Bad MB? Maybe?
Any and all replies are appreciated.
Thanks