Check your car's exterior lights regularly (at least once a week, or before a long journey). A faulty bulb can be dangerous, and is also against the law. Having a stop-light or a number plate light out is a perfect excuse for the police to stop you...
You'll need a bulb of the right type, and you may have to remove some trim to get at the bulb holder - see your car's handbook, or your Haynes Service and Repair Manual, for details.
Here's how to change a typical headlight bulb.
1 Disconnect the wiring plug from the bulb ...
2 ... and peel off the rubber cover.
3 Squeeze the legs of the spring clip together to release it. Move the clip out of the way and pull out the bulb.
4 The bulb will have tangs like this round the edge so it can only be fitted one way.
5 Fit the new bulb, making sure it's the right way up, and secure it with the spring clip. Remember, don't touch the glass.
6 After fitting the new bulb, check that the lights are working normally before you use the car.
- It's a good idea to carry spare light bulbs so you can replace a blown bulb immediately. (This is a legal requirement in many countries.) You can buy a bulb and fuse kit tailored to your car.
- If you replace a bulb but it still doesn't work, look for corrosion in the bulb holder or the wiring connector. Squirt a bit of water dispersant spray onto corroded contacts.
- If a tail light goes out or dims when the indicators or brake lights are operated, this is usually due to a bad earth connection. Find the earth points using the wiring diagram in your Haynes manual.