2001 a6-need help
 

Hey all,
I recently purchased a A6 2.7T. and now I'm having error codes all over the dash.

I put aftermarket D2S HID bulbs in- I believe that they were the same ones that came in it-although they did cost like a third of the OEM from Napa.

Since then, my ABS, Air Bag, Esp lights all have come on.

Additionally, I had bulbs in my third brake light go out--I just ordered a new led "universal" unit to replace because the sockets seemed loose.(new bulbs would flicker on and off.

The head lights don't always come fully on. and the car keeps beeping at me.
also the check engine light came on and is pinging the codes for the O2 sensor which was put in new in september.

any help would be greatly appreciated.
Thanks