Every time a bulb is replaced, disconnect the lead from the negative end of the battery before replacing, and be careful as the bulb could be very hot if it has just been used. Always inspect the bulb contacts and holder for clean metal to metal contact and clean away any corrosion or dirt if fitting a new bulb. Make sure that bayonet type bulbs have live contacts firmly against the bulb contact and the new bulb is of the proper rating and is totally clean. Some switch illumination or pilot bulbs come integral with their switches and cannot be renewed separately. For interior or vanity mirror lights carefully prise the light unit or lens from the position, renew the bulb(s) and refit by reversing the removal process. For front reading lights, remove the light lenses, screws, lower the console and change the bulbholder and wedge base bulb. For glovebox lights, empty the glovebox and undo screws, remove retaining clips and remove the bulbholder and bayonet fitting bulb, and make sure the dimmer sleeve light aperture is pointed toward the glovebox window when the light is refitted. For door edge marker lights, push the light unit upwards, withdraw the light unit, twist the lens from the bulbholder and withdraw the wedge-base bulb. For the automatic transmission selector panel illumination bulb, you take the handbrake, remove the trim panel with great care, press the selector panel again, and remove the bulbholder. Not all switch illumination bulbs are renewable separately, so take the switch off and turn the bulbholder to get at the bulb. For instrument panel bulbs, use the proper instructions. For front and rear ashtray illumination bulbs remove the ashtray, undo screws and pull out the bulb holder. For cigarette lighter illumination bulbs, remove the centre console, the retaining tabs and the bulb. For feet light, remove the light unit by prize down the light unit, disconnect the wiring plug, unclip the metal cover and remove the wedge base bulb. Refitting is normally a reversal of removal for all components.