Modifying The Humbucker For Coil Cut
Step 1) First I remove the humbuckers cover and unscrew the single coils from the chassis (the metal back plate).
Step 2) Next I disconnect the wires which connect the single coils to the chassis. Make sure to note where the wires connected before you removed them.
Step 3) Now it is time to cut the wire which connects the two single coils. This part takes a lot of patience and skill to do properly. Cut the wire which connects the two single coils in the center of the wire. Then, strip the ends of the two new wire tips. In the last picture of this step you will notice that I have prepared a 12 inch segment of four lead wire. I have stripped about 1.5 inches off of the 4 lead wire exposing the four colored wire.
Step 4) In this step I reconnect the single coil pickups but now with a wire from the 4 lead wire. Be careful on this step. When the wires have been soldered together then the freshly soldered metal parts will have to be covered so that they can not touch any other metal parts. If you plan to use heat shrink then do not for get to put on the heat shrink before soldering.
Step 5) I then connect the white wire from the humbucker to the matching color of the four lead wire and cover the connection with heat shrink.
Step 6) I then connect the black wire from the humbucker to the matching color of the four lead wire and cover the connection with heat shrink.
Step 7) Lastly, I feed the four lead wire through the humbucker chassis so that the single coils can be remounted to the chassis. The last wire (ground) of the four lead wire can now be soldered directly to the chassis and the humbucker can be reassembled
Check if the problem is described here, Troubleshooting Guitar Wiring.
If you still have not found the problem, I suggest you join this forum, The DIY Stomp Boxes Forum. It is an incredibly helpful resource that I have recently started to use when I need help troubleshooting. As long as you are polite and give a detailed description of the problem you are sure to get some valueable help within a matter of minutes. Most people on this forum are far more knowledgable about active electronics than I am and will be able to help you better and faster than I could.