Whenever there is a case of renewing a bulb it is important that mind should be kept on the fact that if the light has just been in use in the bulb may be extremely hot and touching the bulb glass by fingers is not advisable as small deposits may cause clouding. Always inspect the bulb contacts and holder to make sure there is clean metal-to-metal contact and clean up any corrosion or dirt before putting in a new bulb. For bayonet type bulbs, make sure that the live connections are pushing firmly against the bulb contact, and make sure that the new bulb is of the correct rating and thoroughly clean before fitting. For headlight maintenance The process is to remove the headlight unit, push the retaining clips to remove the plastic cover, turn the bulb holder to tear out, and pay attention to not touching the glass of the bulb. The same care should be taken for dipped beams, sidelights, front fog lights, front direction indicators, direction indicator side repeaters, headlight-mounted side markers, rear combination lights and number plate lights where specific steps will be taken for each type, including disconnecting wiring plugs, releasing clips and twisting or pulling bulbs from holders. The high-level stop-light, though, is lit up by non-renewable LEDs, and if they aren't working properly, the whole thing has to be replaced.