Man o man.
So I had my car painted and and taillights were removed as well as front lights. So when I went to pick up the car I put the taillights back on to drive it home and noticed the lights not working.

Looked at the Tail Light fuse on the IPDM (position 71)....fine (BTW this seems to be the fuse for the night time running lights in the tail light assembly)
Looked at the Stop Light fuse on the fuse panel on driver's side kick panel....fine
Checked the continuity of each bulbs; filaments - fine
Turned on the nighttime running lights and saw one of the filaments of each bulb burning.

So figured it must be the switch.

removed the switch and tested continuity for when depressed and when not depressed. It passed that test.

connected the switch back up, but not installed on the bracket - no brake lights (with the plunger of the switch is not depressed the switch should close the circuit)
wiggled the wires and sometimes the brake light would come on. (oh god please let it NOT be bad wires)

Pressed the plunger a few times and inconsistently the brake light would come one. (whew ok seems to be the switch, not the wires)

Took the switch out and dismantled it to see how it works.

• A plunger with a hole in it, that accepts a spring.
• one blade has a thicker bar with two tangs
• one blade has a thinner copper bar, with two tangs and what looks like Points Contacts (thick old cars' Points within their distributors)
• when the plunger is depressed the plunger's end, which has a taper, pushed the copper contact away from the stationary thicker bar.

With the plunger fully extended there are a pair of contacts that weren't consistently making contact..the gap was about as thick as a sheet of paper. (periodically the thinner contacts would make contact)
I used 1000 grit paper to clean up the contacts, and bent one side of the contacts (the thicker tangs) so they were touching as default.

I should have taken pics...sorry.

any way the lights are working.

 

Nice writeup. These switches are pretty basic in design and easy to take apart and clean/service. Over time they do get pitted from electrical contact/arc-ing. As you've already done, some light sanding and maybe a little dielectric grease goes a long way in keeping them working. I also like to grease the plunger neck to keep the switch operation quiet (no squeaks or creaks).
I've done this exact same service on the switches used for cruise control on the clutch and brake pedal, basically the same design/process.

Cheers!
-Icer

 

Yeah I should have used dielectric grease....and I should have taken pictures....just impatient.

I may come back to this and post pics at a later date once I have the car back together.