'62 Strat pickup repair
This morning I had in my shop a bridge pickup from a 1962 Fender Stratocaster. The pickup was not producing any sound when installed in the guitar and when hooked up to a mulitmeter, showed no resistance. This means that there is an open circuit somewhere between the positive and the negative lead wires. It is important to be very careful when working on this type of vintage gear in order to preserve the original tones of the guitar, so a number of steps were taken to carefully diagnose the source of the problem.
First, upon removing the cover I could see that this pickup uses Formvar wire, a common wire of the period, which gives it that coppery look. There is a thin layer of wax on the pickup meaning it was at some point wax potted.
Next I inspected the condition of the actual Formvar wire and I could see that there was no visible damage. My next step was to heat up the solder on the eyelets and add a little bit more solder. This connection can get dirty over the years and cause a bad connection.
If heating up the eyelets had not worked my next step would have been to disconnect the finish and unwind a few coils to try to find a break. As a last resort I would have removed all of the old wire and solder, rewound the pickup with vintage-spec wire and waxed it.