Halogen headlamp bulbs
 

Are halogen bulbs ok to use in headlamps?

I ask because I fitted two new one's when I changed the broken unit and since then they don't seem to be 'dimming' during bright sun! I'm sure they did before!!

you will tend to find more halogen bulbs available than the older types, plus only halogen bulbs will have the correct base fitting to go in to the headlamp. if your car is anything like my 02 V70, it does not have dim dip, just day riding position on the switch, so puts the headlamps on dip beam, normal brightness. ;)