To change the courtesy light, a small and flat-bladed screwdriver is used to carefully lift the light lens and to free the bulb in the light unit contacts and then install the new bulb in place and then re-connect the light lens. To install the front seat reading light, gently poke the courtesy light assembly out of the overhead console, unconnect the wiring connections and use the bulbholder to unscrew the bulb then slip the new bulb in, reattach the holder, reconnect the wiring, and re-poke the unit back in place. For the rear seat reading lamp, the process is the same: push out the light unit, break a connection of the lighting, take away the bulb, fit the new bulb, reconnect the wiring, and re-clip the unit. To perform maintenance on instrument panel illumination and warning lights, loosen the instrument panel, counterclockwise twist the bulbholder to extract it, make sure that the new bulbs fit the appropriate rating and replace the bulbholder and instrument panel. In the case of the glovebox illumination light, open the glovebox, extract the light assembly, unscrew the bulb, fit the new bulb and reconnect the unit. In the case of the cassette storage box illumination bulb, simply slide the storage box out, unhook the wiring, disconnect the holding clips, take out the bulb and then reconnect in the opposite order. In the case of the cigarette lighter/ashtray illumination bulb, you will have to carefully pry the surround, remove screws to unlock the control unit, open the back of the cigarette lighter, unclip the bulbholder and replace the bulb then put the parts back together in the order in which they were removed. In case of heater control panel illumination bulb, remove the panel, disconnect the wiring, unclip the bulbholder, remove the bulb and re-attach in the same order. Finally, switch illumination lamps are attached to the switch assembly and the entire assembly must be replaced to change bulbs.