It’s really difficult to impossible to repair Fender style pickups when the beginning wire is broken off at the beginning of the coil.

1. You need to have a qualified repairman attempt to do this kind of work and often ends up to having the coil rewound and at times unnecessary. At times the beginning hookup wires are pulled out of humbucking pickups or the pickups stop working because of cold solder joints.
2. On older humbucking (Patent Applied For) models the beginning hookup wire extended from the square hole on the bottom of the molded bobbin. If the beginning wire gets pulled out, the coil will have to be unwound. After removing the magnet wire and reconnecting the beginning wire the coil can be rewound using the same wire.
3. If the outer wire in the humbucking pickup gets broken or pulled out, it is easy to remove the insulation tape and resolder the beginning hookup wire. It may be necessary to remove a turn or two but this will not effect the tone of the pickup.
4. On later model humbucking pickups the beginning wire is connected to the hookup wire after the bobbin is wound. The broken beginning wire can be fixed if you have enough beginning magnet wire to connect to, if not then the coil will have to be unwound.