Repairing A Faulty Switch
Yes, You Can
Here at Shortscale.org, we believe in the idea that a penny saved is a penny earned. Since guitar components can cost you more than just a few of your pennies, once again we have an Aug-created guide to keeping your three-way switches working for years to come.
Step 1: Open for Business
The purpose of this will serve two causes. One, if you aren't familiar with soldering, it won't matter...and, if you have a vintage instrument, replacing a component can greatly devalue your instrument.
You are reading this, most likely, because your switches are either scratchy or only work part of the time, so here's my suggestion:
Here's my 100% original 64 Mustang. The test subject...
After removing the strings, bridge and pickguard screws, carefully pull the pickguard from the body. Odds are, if your instrument is 40 years old, you won't want to inadvertantly pull any wires loose.
Once off, you'll probably notice this foam here, positioned under the switches. Leave it alone, if possible, it's there to keep the switch terminals from touching the copper-shielding. Furthermore, if it's really old, it's probably hard as a rock.
Here, you'll want to gently flip the pickguard upside down and rest it on the guitar body. A towel between the pickguard and the body might be a good idea.
Step 2: Pull Your Part Apart
remove the screws holding the switch in place and, using a good set of needle-nose pliers, GENTLY pry back the prongs holding the switch together...
This next part is just unavoidable, and shouldn't deter anyone from purchasing your instrument...especially if you take a moment to explain what work was done.
Using a soldering iron (if available) heat up the small wire on the body of the switch (not at the connector!!!) and gently pull the switch apart. You'll want to be very careful here, as you'll need to pay close attention to how this thing goes together.
After pulling it apart, you should have something that looks like this...
Step 3: Clean Up
See the 8 connection points? Scrap those bad boys with a bit of sandpaper or a sharp metal edge (like a knife) If you see any dirt/grease/whatevaz...clean that off, too.
Clean/scrape these too:
Step 4: Voila!
Now...put everything back together, resolder your ground and you are done.