JoeM

In my case the bulb was good. I did continuity checking with a VOM and found that the common contact in the socket was not making electrical contact with the side of the bulb. I cleaned the bulb and the socket contacts (socket bulb goes in). I found little corrosion or gunk. I also checked the plug between the socket and cable. The contacts looked a little worse here, but cleaning did not help. I carefully pulled the socket contacts out so that they would have a little more spring pressure against the bulb. Pulling the side contact out solved the problem (for now). I am guessing that the problem with these things is more due to metal fatigue on the side contact reducing the contact pressure rather than dirt/corrosion. If that is true, the problem will be back.

I just tried this on a '99 ES300 and broke one of the clips holding the black plastic cover on. Neophytes like myself need to know that these clips are two piece devices that need to be removed carefully rather than just pried. You need to slip a knife or somthing between the cap of the clip and the bottom portion of the clip. Then use the knife to pry out the top portion of the clip. It will come out easily. After it is removed, the bottom portion of the clip will also come out easily. The top portion of the clip has a pin that spreads out the bottom piece of the clip to hold the clip in the hole. Be careful to pry between the top and bottom portions of the clip and not between the clip and the black plastic cover The top portion of the clip is almost knife-edged due to the chamfer.