- I would check the connections on each end of the cord. The solder joints can become fatigued and break shorting out the signal.
- Check the length of cord for internal breaks. At times the center conductor or shield can break and become intermittent causing the instrument to short in and out.
- Check for worn plating on the plugs that can oxidize causing faulty contacts with the jack.
- Check the jack internally for worn plating. The majority of jacks are machined out of brass and can oxidize if exposed to the elements. Cleaning the jacks will work for a while but if the unplated area continues to be exposed for a period of time the oxidation can return causing the signal to become interrupted.
- Check for bent or oxidized contacts on switches and even volume controls. Worn switches can easily become oxidized from constant use and build up debris especially from sweat and humidity. At times a solder ball can get lodged between contacts and even inside the volume or tone controls. They can short out the signal and cause aggravation when trying to determine the problem.
- Check for cold solder joints in pickups and other connections in your instrument. Older solder joints can also oxidize causing the signal to fail in different environmental conditions.
- Inner coil pole corrosion (ICPC) can cause the pickup to cut in and out. This is due to excessive moisture over a period of time within the bobbin and eventually corrodes the pole piece and eventually breaks down the insulation on the magnet wire on the inside of the coil. When the insulation breaks down on the magnet wire, the exposed copper wire oxidizes and can break. This causes an open circuit within the bobbin and rewinding is most likely needed to repair the pickup. This usually happens on Fender style single coil pickups where the moisture can permeate through the covers and eventually causing the magnets to rust.
WRITTEN ON JUNE 12, 2015, BY