Vauxhall Astra Owner's Manual page 232

230 Vehicle care
Low beam (1) outer bulb.
High beam (2) inner bulb.
Low beam (1)
1. Rotate the cap anticlockwise and
remove it.
2. Disengage spring clip from
retainer by pulling. Withdraw the
bulb holder from the reflector
housing.
3. Detach the bulb from the bulb
holder and replace the bulb.
4. Insert the bulb holder, engaging
the two lugs into the reflector
housing and rotate clockwise to
secure.
5. Push spring clip back in place.
6. Fit the cap and rotate clockwise.