So I'm driving down the interstate and I decided to use my cruise control...it would not turn off after that. Not when I hit the breaks, not when I switched the cruise control to off, not after turning the car off. I had to pop the hood and pull the fuse to get it off. What the hell? Why would that happen? 94 3.4l.

 

woh, never heard of that happening.

 

Yeah at first it wouldn't shut off. Then it started accelerating. It even surged a few thousand rpm when I put it in neutral.

 

Sounds like the box that controls it is messed up

 

yep or the switch on the blinker is wack

 

Now that would tend to wake you up really quick. Glad you controlled it and didn't kill yourself.

 

Well base on the DMV requirement the power supply to the cruise control has to pass through the brake switch. If the brake light go on the cruise system has no power. The system requires two completely separate failures to happen for it to stay on, at least on the electrical side. Most of the time that I see an issue with "not turning off" or "slow turning off" it ends up being a stuck or sticking cable either cause by rust, ice or mis-routing.

 

damn thats just ridiculous! camaro computer and electronic systems seem to have a mind of their own - and frankly scare the hell out of me!

 

Yeah it was def a little scary when it started speeding up.

 

I'm guessing by DMV you mean NHTSA. If DMVs made design rules we would have 50 different sets.

As for Cruise system power, 12v is supplied directly from the fuse block to the module any time ignition is on. The same fuse sends a 12v signal through the brake (and clutch if applicable). Depressing the pedal removed that input (cruise cancel). A third 12v supply is sent through the stalk switch when cruise switch is on. (Based on Page 8-714 of my FSM)

So pressing the clutch or brake pedal still leaves 2 valid 12v power sources going to a malfunctioning cruise control module. The CCM is designed to always fail in a disable mode. But 30+ years in aircraft electronics has shown me any circuit can have unintended behaviors.