The car will not do anything when the key is turned over.
The radio plays, lights come on, but will not start. Usually this takes about 5-20 minutes before it will start. Yesterday it quit and it will not start.
Battery is fine, radio still playing, just will not start. Could this be a key or ignition switch problem?
Answer:Yes, it sounds like you have either a bad ignition cylinder or possible bad resistor key. Your vehicle has a security system that reads the little chip in the key and is looking for a specific resistance. It is called Passkey.
Sometimes the chips can come loose in the key and not make contact properly inside the cylinder. Most often, though, it is the ignition cylinder itself that goes bad. The wiring from the cylinder down to the base of column will get worn and eventually break. If so, the cylinder needs to be replaced.
You'd really need to get this checked out at a dealership or shop that has a VATS system tester. Then they can tell you what the problem is.
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