Cruise Control Wonky - Any Ideas?

[Ben]

So the cruise control has started going wonky on my 08 F250. Every once in a while, when I turn it on and try to set it, it simply doesn't do anything, as if it were off. If I shut the engine off and restart, 9 times out of 10 I have cruise control again. Apparently there is no fuse for it on F250s, and if there were, I would expect it either would work all the time or not work all the time if the fuse was bad. It's supposedly controlled by the Powertrain Control Module.

I'm wondering if something like this, that's computer controlled, fails intermittently, if there is some fix via the diagnostic hookup at the shop, or even if it's something minor like this, if I would be stuck buying a brand new brain? I wouldn't mind spending a couple hundred to get it fixed since I use it a lot, but if it's a $1000 fix, I'd rather just live with it.

[charby]

Head to autozone or whatever parts store you like and have it scanned, might have a error code or the PCM is failing.

Load test your battery or batteries.

Check the brake pressure switch.

[Ben]

I have a scanner, no error codes. I saw something searching around about the brake pressure switch, but wasn't sure that would be it with the whole working normally after cycling the engine on and off. Couldn't hurt to have a peek at it though.

[Northwoods]

I don't know how they set it up on pass-trucks, but the big rigs use something 4-5 different ECU's to operate cruise control (ABS, engine, transmission, wheel speed, and radar if equipped). Could possibly be a problem with any of those.

[sanglant]

umm, switch going out? if trying it again without the restart works that's where i'd be looking.

my car's switch* acts up in high humidity, but i don't drive enough right now to get it fixed.

*that's the set/coast/resume switch, and just on set.

[gunsmith]

our old cars switches always act up but its not humidity its dust.
we spray wd40 on it and it usually works again.

[birdman]

I don't know how they set it up on pass-trucks, but the big rigs use something 4-5 different ECU's to operate cruise control (ABS, engine, transmission, wheel speed, and radar if equipped). Could possibly be a problem with any of those.

A code sweep will query those to, they all toss codes over CAN to the diagnostics...which were mandatory 2008+ model year.