Need Help in solving this issue with my humbucker pickups

[owasis]

I replaced the electronics (humbucker, pots, switch) on my guitar. The new pickup humbucker is form musiclily (basic series). I wrapped the cavities(even the pickup cavity) with aluminum tape. Followed a wiring diagram for single humbucker/1 vol/1 tone control with switch to change humbucker to single coil. At first all was good, but after a day of test play I noticed no sound is produced when a switch back from single coil to humbucker. I checked the connections everythimg was good. When I tested it with a multimeter (Touched the wires with probes) the humbucker produced sounds again. The single coil is okay, its when i switch back to humbucker it produces little sound or no sound at all.
Only way to revive it is by touching the wires with the probes.
Please help in solving this issue.

[newey]

owasis-

Hello and Welcome to GNutz2!

If it worked OK, then suddenly stopped, it's not a wiring issue, it's a bad connection. If you can access the cavity without removing the strings, hit the solder joints with your iron to remelt the joints, that may fix it. Gently tug each of the wires to be sure it's solidly connected.

If you have to remove a pickguard to get at the wiring, I'd do the same, it'll just be a larger PITA.

If that doesn't work, some further investigation with your meter will be in order.