Ok, I have an '05 ES330 with a strange tail light problem. The tail light I'm referring to is on the left side of the trunk. This is what happens, and is very repeatable:

1. I start the car and turn on the lights.
2. The light indicator on the dash comes on.
3. I get out, and sure enough the tail light is not on.
4. I open and close the trunk, and the light comes on the moment the trunk closes.
5. No amount of messing around with the wires or bulb while the trunk is open will make the light come on. Only closing the trunk will do it.
6. If I stop and start the car again, I have to repeat the same process. If I open and close the trunk before I start the car, it doesn't help. Once the tail light comes on, I could drive 300 miles without a problem.

Obviously there is a bad connection somewhere. I've looked at the wiring, but don't see any signs of moisture or corrosion. I can't really tell where the wiring harness leads.

Ideas?

 

Very strange indeed, only suggestion I have is to try a new bulb or swap the bulb to the other tail light to see if the problem moves to the other side. The filament could have a small break that opens up when it cools off then reconnects when the trunk is closed. Probably a long shot but its easy and inexpensive to try.

 

Funny I had the same issue with my car a couple months back. After a while I just decided to replace the bulb and it went away for good. The bulb must have a small break, but isn't fully burned out yet.

 

As suggested, first try changing the bulb. If that doesn't work, than look closely for a break in the wiring harness where it attaches to the trunk hinge as it enters the trunk from the body.

Over the years, frequent opening and closing of the trunk, can cause a break in a wire in that location.


Phil

 

Thanks everyone!

Yeah, I guess I never thought about the bulb filament being damaged. It kind of makes sense though, because it only comes on if there is voltage applied to the bulb and gets a quick jolt from the trunk closing. Once it comes on, it stays on.

I'll change the bulb this week and post the results. Thanks again!