John Paul, AAA Northeast's Car Doctor, answers a question from a reader who ran into trouble after installing a new ignition switch. The post Did swapping an ignition switch do more harm than good?

When the ignition key is turned, it rotates a plastic disc inside the ignition switch. A small metal part, called the detent plunger, slides into notches, or “detents,” in the plastic disc.

Using your wiring diagram, find the wire responsible for activating the starter solenoid and install a switch as far from the ignition as possible in that circuit (you don't want the potential ...