Your pop is correct. Inside the switch assembly are four sets of spring-loaded contacts. There is a fixed contact and its mate is on the end of a strip of spring metal. Each strip has a small plastic "nail" that pushes on the strip to turn that switch off. The head of the nail pushes on the metal strip. The pointed end of the nail runs on a series of ramps molded into a round plastic disc that rotates with the key. As the disc rotates, the four nails raise and lower at various times to turn the four switches on and off.
Over time, arcing causes resistance to develop across the sets of contacts, and current flowing through them creates heat. As that gets worse over time, that heat melts those plastic nails. Once the head of the nail melts enough, there is nothing left to push on the metal strip, so that switch will not turn off. It is also possible for the melted plastic to ooze under its set of contacts so that switch will never turn on. It is not uncommon to see one where the "accessory" circuit, (which you described), will not turn off, and a short time later the "starter" circuit will not turn on. I have even seen owners having to play with jumper wires and paper clips to drive these cars.
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Tuesday, February 6th, 2018 AT 2:46 PM
