I've got a 2001 S-10 extended cab and the brake lights stay on after I have driven the vehicle. The kicker is the CHMSL (center high mounted stop light) does not stay on, but does come on when I apply the brakes. I replaced the brake switch and that seemed to fix the issue, but it is back again. The only way to get the rear brake lights out if they are stuck on is to jiggle the brake pedal. Eventually, you can get them to go out. I saw in another thread where someone mentioned adjusting the brake switch. I did not do that (did not know there was an adjustment or how to do it) when I replaced the switch about 8 months ago

I have searched various threads on this sight but have not found an answer to my predicament. After driving, the brake lights will stay on - but only the two rear lamp brakes, not the CHMSL light. CHMSL functions as it should when brakes are applied as do the rear brake lights if they are not stuck on. I replaced the brake switch and it helped the situation for awhile, but now brake lights stick on most of the time. Only way to get them to go off is to jiggle the peddle numerous times. Sometimes shutting the door will cause them to come on again - very frustrating...

 

If the CHMSL goes off, then the switch is doing what it is supposed to. Sounds more like something is wrong inside the multifunction switch.

 

I had the same issue with my own truck a couple months ago. After days of checking wires and switches to no avail I finally found the problem.

The problem was a faulty CHMS relay. You can test it easily enough by swapping it out with one of the many identical relays used in this truck. If memory serves both the horn relay and the fog lamps relays are the same as the CHMS. But double check the numbers on them first before you try to switch them.