One of the issues I ran into after full assembly of my car was that I had no instrument cluster lights. It's been a nuisance problem all summer and now that the weather has changed and am not driving it much I decided to pull the dash apart and see if I could determine what the problem was. The dimmer had worked before I took the car apart.
I was thinking that it might be the switch but after pulling it out and putting the tester on it I could see that the copper was very corroded and there was no continuity between the contacts. I fiddled with it a while trying to take it apart and then decided that I didn't want to break it so I was pretty much decided on buying another one when an idea was hatched.
I searched around to find a way to chemically clean the copper to get the contacts working and found this:
http://www.instructables.com/id/How-to-perfectly-clean-wires-in-minutes/The basic details are this (in case the other site goes away).
2 small jars/containers.
1 jar with a tablespoon of salt and fill the rest with vinegar. Enough salt so that no more will dissolve into the vinegar. This makes a mild acid.
The second jar is water with a tablespoon or so of baking soda. Enough so that it's cloudy. I didn't really measure these out closely. This makes a base to neutralize the acid.
I dunked the dimmer switch into the acid and swirled it around for 2-5min occasionally twisting the switch so it would clean everywhere. I could see the green corrosion turning back to a nice copper color.
After that was done, dunk/twist the switch in the baking soda mixture to stop the process.
I then rinsed with water and blew dry with the air hose.
Another test on the electrical meter and it was working perfectly. The resistance changed while twisting the switch and all the contacts now work. I'm going to install/test again today and put the dash back together. Very nice without having to take the switch apart.
Hope this will be found useful.
