Garage door opener light not working

So I had to work on my automatic garage door opener today, just a loose connection. So I took a look at the light and curious why it was never working.
I notice a set of copper tabs (spring like) like an on/off switch similar to the insides of a relay. Anyway when I join them the bulb goes on and off when disconnected.
So how do I try and find out what activates this relay of sorts? thanks

 

Moved to Garage Door Forum.

 

Please give us a photo, and also make and model of the opener.

 

Sears Roebuck.... Digital Control over 15+ years old
Model #139 653000
will try a picture but may be tuff

 

Well over 15 years..... probably closer to 30 years old.

You're looking for a thermal light timer. They are long gone. You could replace it with a solid state module but it's tough as there is little room. It's easier to mount a motion sensing light to the ceiling next to the opener.



Power is applied to the bottom two contacts when the motor is running to heat a thermal strip. From the heat the bimetal arm closes the two contacts and power is sent out on the top terminal to the bulb. When the motor stops running, the bimetal cools off and the light turns off.

In the picture the arrow is pointing to a break in the fine nichrome heating wire. That's most likely the problem with yours too.