W520 not charging battery while in docking station

[criza]

Hi

I've got a W520. When connected to the docking station it shows charging in the power manager, but the battery is unloading at the same time, so it says it's charging the battery but it really doesn't. The battery is constantly unloading, so neither the power supply works when docked, although the green light on the docking station is on. I tried to clean the contacts but it didn't change. I'm using the 170W AC adapter and if connected directly to the notebook the battery is charging and it works.

I can't tell if it's the docking station that has the problem, or if it's a part of the notebook, as I don't know what is responsible for the charging when attached to the docking station. Any help would be greatly appreciated. Thank you.

/C

PS I have all the newest updates. I did install a BIOS update, and even a battery update some days ago. After that everything was still fine. The problem occured only yesterday. I restored the bios defaults and I also tried the CMOS clearing trick, no success.