97 850 Sedan. How to change headlight bulbs

These are halogen bulbs that you need to access from behind the headlight. In most cases you can reach in, gently twist the bulb loose, and remove it from the socket, then replace it with another bulb and reverse the procedure. Be careful not to touch the glass on the bulbs as this will shorten their lifespan.

Thanks for the info.

I've changed mine but it still doesn't work, any ideas? Checked fuse box, all ok

A relay delivers the power to headlights. The headlight switch only turns on/off the headlight relay. Check if the headlight relay is bad, or if its fuse is bad. In rare case, the headlight switch itself is bad; very rare.

Additionally, the headlight switch (the one on your dash) has been recalled (free to fix by dealers even not-first owner). Not sure free to replace by now (2018). You can replace it yourself or by a garage. The switch is about $70 online. https://www.eeuroparts.com/Parts/9400/Headlight-Switch-30739333/ For more info on free recall on the headlight switch: https://volvoforums.com/forum/volvo-s70-33/help-headlight-switch-36543/

Many thanks, problem resolved!