Sorry if this is a repost. Couldn’t find it if is.
09 s60 2.5t
replaced both low beam bulbs. They worked fine for 2-3weeks. Now I’m getting a bulb failure but only with the turn signal on. The bulb dims and starts flashing with the turn signal. What’s my first step to getting this fixed? Thanks in advance.

 

are the headlights still working ok? its really not that uncommon for both headlights to go out relatively close to one another, particularly if you leave them on as running lights. As to the turn signals, did you replace those bulbs yet? I'd start by replacing the bulbs and while you have them out check the sockets for any signs of corrosion/looseness. Then check voltage at the socket and on the ground. could be a bad bulb, a socket issue or a bad ground. Last it could be the flasher relay or the multi-function stalk.