Clamp-On Test Clip
Here is how to make a handy test clip. This clip pierces and clamps on to a wire without much fuss or damage. Its great for finding what all of those wires do under your dash board.
1. Take a spring type clothes pin apart.
2. File a 'V' shaped notch on one side only.
3. Drill a small hole at the bottom of the notch thru to the outside.
4. Drill a second hole to pass the wire thru.
5. Reassemble the clothespin.
6. Insert the pin from the outside to just contact the inner facing surface.
7. Bend the pin over.
8. Hotglue the pin.
9. Solder a wire to the pin.
10. Run the wire thru the second hole for strain relief.
To use this device, place the wire into the notch and pinch that end of the clothespin to make contact. After that, the spring should hold it in place.