Got good anwers on my question about the yellow brake wear indicator light and am going to go the the junk yard and pick up a few in hopes of getting a good one cheap.

After the anwer about the problem being related to the seat belt indicator caused me to start the car without my seat belt connected. I did it, and the red seat belt light no longer stays on or makes a noise so that appears to be a very good lead to the solution. The yellow brake light does still stay on all the time.

The next question is about seat belt retractors. My 1980 300sd driver side seat belt will only pull out a few inches at a time and it takes many pulls and jiggles to get it on.

A while back, I took it apart and sprayed the retractor with carb cleaner and that made it work perfectly for a month or two, then it returned to it's old ways.

I was wondering if I just need to buy a new one or whether there is some way to clean and lube this so that it will continue to work smoothly.

Thanks