The right hand HID low beam on my 2003 Volvo XC70 was about to die. So I replaced both. And since I did not like the mismatch in color between low beam and the rest, I replaced everything.
Always check which lights your car has before you order new ones! Mine has D2R type Xenon lights, but yours might use a different type!
The OEM bulbs seem to be OSRAM Xenarc 66050 D2R bulbs which have a light temperature of about 4100-4200 Kelvin. My car had a Philips on the left hand side and an OSRAM on the right side…
The 66020 is no longer produced, it has been replaced by the 66250.
For high beam I ordered Philips WhiteVision Ultra H7 12V 55W PX26d 4200K
For fog lights I got Philips 12258WVUSM White Vision Ultra H1
Both sets came with a pair of matching W21/5W bulbs which replace the parking lights.
Installation can be done without removing any parts from the car, but it is tight, will cause some frustrations and you may end up breaking a bulb. If you don’t want to risk anything: remove the bumper and the head light units. I didn’t, because I didn’t want to.
The HID is easiest to replace on the right hand side, there’s a bit more room for your hand to work. Remove the cap, loosen the clamp, pull the igniter with bulb out carefully, disconnect connector from the igniter, remove the bulb from the igniter (twist counter clockwise).
Installation is the reverse of removal.
Be very careful not to damage the bulb when reinstalling in the unit. Look through the glass of headlight unit to align the bulb when installing it. Also make sure the clamp is in place correctly.
The high beam is a lot easier, remove the cap, pull the connector off, loosen the clamp, pull the bulb out.
Parking lights can be a pain. There is hardly any room to work. Remove the caps of the low beam to create some extra room for your hand. Use a flathead screwdriver to rotate the holder.
The left hand side bulb rotates counter clockwise to loosen, but the right hand side bulb must be rotated clockwise!
The fog lights are easy as well, just pay attention to the orientation of the bulb when installing. Otherwise the holder won’t thread back in properly and the plastic can break.