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Neutral Safety Switch? Transmission Interlock Switch?

I just have a general question about the difference between a “neutral safety switch” and a “transmission interlock switch”. Can anyone explain the difference between the two? Also what is the mechanism that locks up your steering wheel and ignition once you move the steering wheel after the car is turned off. As far as I know this is the mechanism that is preventing the ignition from turning and you need to wiggle the wheel left and right while turning the ignition to unlock it before you can start the car. What is the mechanism called? Thanks.

I can’t really explain the difference but the neutral safety switch prevents the starter from operating unless the gear shift is in neutral or park. Otherwise the car would move right away when the car was started. The interlock switch may be refering to the switch that prevents moving out of park unless the brake pedal is depressed.

For the steering lock, inside the hub of the steering wheel, where the turn switch stalk goes in, is a 3-4" sheet metal pin wheel with slots all around it. When you turn the key off, a button pops into one of these slots to lock the wheel. I’d have to look at a picture of the key mechanism but I assume there is a device that pushes that pin up in place when you turn the key and also does not allow the key to turn until the button is released. That’s that part that must be sticking and needs replacement or lubing I would think.