Dell XPS 12 power adapter not recognised possible solution
I had an issue on my Dell XPS 12 9Q23 where out of 3 power adapters only one would charge. I also have a 9Q33 which all 3 charge ok.
The solution I found was that the plug that goes into the laptop was to short exposing 2mm more plug by cutting back plastic solved the problem.
How did i test this - Simple remove back cover and plug in power supply turn on laptop and press F2 to enter bios adapter was recognised. Put back cover back on and repeated Adapter not recognised. Carried out above and plugged back in and adapter recognised.
This may well be the case if the adapter was not dell sourced or may be a slight manufacturing issue.
However I now have 3 adapter charging both 9Q23 and 9Q33.
It could also work for other model but always d the test above first.