2015 Volvo S60 t5
Today after I replaced the driver side bulb (I’ve changed the low beams at least three times within 6 months),low beam malfunction light disappeared but now neither side are working. High beams and daytime running lights are working fine. I was thinking possibly a fuse short, but I’m not able to locate it on a fuse box diagram so I’m not sure if that’s even a thing for this make & model. Any input is greatly appreciated as I know absolutely nothing about cars. They are halogen by the way (not sure if that matters)

 

Could be one or both balasts that need to be replaced. One thing to try first. Instead of just replacing the one known blown bulb, replace both and make sure they are the same brand. I would actually try a different brand then what you bought for your new replacement. I ran into an identical problem but it was with xenon bulbs.

 

Silly thought, but is there a chance you are turning your headlights to Auto and not On? From what I searched online, there is no headlight fuse. I think this is controlled within the CEM like the older models. Are you touching the glass bulb of the new headlights with your fingers? This will cause them to burn out very quick due to the oils on your skin.

As far as I know, the halogen bulbs do not have a ballast, only the HIDs.