Tail Lights intermittently failing

My 2004 Lexus RX330 has a problem with the tail lights. When the lights are turned on, a dashboard indicator shows a tail light out. Sure enough, one of the tail lights is not lit. If I tap on the lens cover the light comes on! It stays on until the next time the headlights are turned off and then back on. The bulbs and fuses must be good, since the lights do work (after the tap). I suspected a loose connection, but why would it recur every time the lights are turned on?

You may need to clean the contacts where the lamps go. It may aso be a bad lamp.

I would remove the bulb, Since I have it out, I would replace it, the lamps are cheap. When it is out take a look at the socket. Does it look nice and shinny? Make sure it does. You might even try some contact cleaner, I would, but I have some handy in my garage.

There are other possibilities, but they are far less likely.

There is a marginal connection. You tap and it makes contact. This draws current and heats up the connection, lamp and socket. Things expand with heat. When you turn off the lights, it cools back down, shrinks and no longer makes good enough contact to illuminate the lamp. Follow Joseph’s advice and clean the contacts. You may want to apply some dielectric grease to the contacts afterward to insure they do not get corroded again in the future.

Thanks guys! I will take your advice, replace bulbs and clean contacts. Will get some contact cleaner when I get the bulbs. Now if I can just remember how to get the panels off the back door to get to the lights…