Page 1 of 1

T420s 65W adapter, Power Manager showing 90W?

Posted: Wed Aug 22, 2012 2:12 pm
by dyst0pia
My 65W adapter gets incredibly hot during charging, and I think it may have something to do with my machine thinking it's a 90W adapter. In the Power Manager application, on the Battery tab, it says "90W AC adapter is attached." Is there some way to fix this? Or do I need to replace the adapter?

Re: T420s 65W adapter, Power Manager showing 90W?

Posted: Wed Aug 22, 2012 5:47 pm
by BillMorrow
good question..
if you have another adapter available, try it and see what the thinkpad reports..
if it reports the correct adapter, then replace the other adapter as defective..
if it reports the wrong adapter then IMO the thinkpad needs to have warranty service done on it..

be sure to reboot to see if this might be a software issue..

Re: T420s 65W adapter, Power Manager showing 90W?

Posted: Thu Aug 23, 2012 1:51 am
by automobus
The signal (on centre pin) is broken, inside the plug, impossible to detect by eye. Sixty-five watt supply has a resistor inside, ninety has not. So, without signal, any adapter is sensed as ninety watt.

Further reading if you are curious:
http://forum.thinkpads.com/viewtopic.ph ... 44#p682644

Re: T420s 65W adapter, Power Manager showing 90W?

Posted: Thu Aug 23, 2012 2:17 am
by BillMorrow
very good work mr. err. . .pada..
now i learn something.. :)

Re: T420s 65W adapter, Power Manager showing 90W?

Posted: Thu Aug 23, 2012 2:20 am
by dyst0pia
Thanks for the info. I can't believe someone actually went and figured all of this out :o