There are several ways to troubleshoot electric guitar wiring. If the guitar exhibits no output from any of its pickups the first thing to check is the wiring at the jack and the switch. One bad solder joint at the output of the switch or at any one of the four connections for the output jack (two at the switch and two where the jack wires terminate) can take down an entire guitar. For multiple pick up guitars with no output from any of the pickups this is a good place to start.

If you don't have an ohmmeter, don't despair, as there is a simple way to troubleshoot an electric guitar without one. Take your hot lead from a pickup and connect it to the wire that leads to the tip connection of your output jack. This bypasses the guitars electronics and any wiring or component problems you may have with the guitar. You just need to make sure that the output jack of the guitar isn't shorted to ground and is properly grounded to the same location as the pickup ground. If you now get output from the guitar you simply need to take the hot lead from the pickup and connect it to each connection in the guitar starting from the jack and working back to the original location for that lead. When sound stops coming from the guitar then you have found the bad solder joint or component. Fortunately there are only a couple of connections and components in most electric guitars so it is not a long or drawn out process. If you connect the pickup directly to the output jack and there is still no signal you will need to get an ohmmeter.

First disconnect the pickup's leads from the guitar and measure it's DC resistance and compare that number to the DC resistance stated on the Tone Chart for the model you have. Close is acceptable and means the pick up is in good working order. If the resistance is very high or infinite this usually means you have a broken coil wire and the pup needs to be either returned or repaired depending on the pick ups age and origin. This could also indicate a bad solder joint in four conductor models. If the pick ups DC resistance is very low or zero ohms this indicates a short in the coils and once again the pick up needs to be replaced or repaired depending on age and origin. If you have an ohmmeter you can also now test for continuity in ground and signal paths. With the pickup's disconnected, start at the input jack and work your way through the circuit until you find the short. Your ground path should always read very close to zero ohms and your signal path should also read zero ohms assuming the potentiometers are set to zero ohms.

When the potentiometers are between the two-meter lead this is a good time to check and see if they are in spec. Disconnecting the tone pot from the volume pot will make your reading more accurate. If you have done all this and the guitar still isn't working take it to a tech. Chances are though that you'll find the problem if you systematically eliminate possibilities in an orderly fashion.