1997 Chevy Truck - Won't shift from park

My truck won't shift from park. After reading other threads, I checked the brake lights and they were not working so I purchased a brake light switch. I have not yet replaced it and then this morning the truck was shifting again. Can a brake light switch work off and on or when it goes out, does it go out completely all the time? Or am I focusing on the wrong thing?

Hi and welcome to AF. No you are not focusing on the wrong thing. The brake light switch is a very big part of this system. Replacing the brake light switch and properly adjusting it would be the 1st thing to do as indicated by the brake lights not working.

If you have this trouble again do this:

1. Turn key to the off & locked position where you can remove the key.
2. From this position turn the key one click towards the on position.
3. With the key in this position you should be able to move the tranny selector to Neutral and start the car and drive as normal.