jayhackett03

i've had the truck a few months. the cruise control was installed in 1992, thats right, 1992. so it's pretty old. when i bought the truck a few months ago, the switch for the cruise on the dash was halfway broken and halfway missing. so, i replaced it, and wired it properly. now once i fixed the switch, i expected the cruise control to work. well, it doesn't. everything appears to be in place. the cable to the throttle body, the vaccum diaphram thingy, it IS getting vaccum, the cruise control computer, etc. any ideas?

Flamedx4

Do you have a manual for it? The SCS stuff had some pretty good installation and troubleshooting guides, how to check each component etc.

(Dragging my mind waaaay back to the dark ages, we've used electronic units (and now it's in the programming for the engine ECU) so long.... The #1 problem with vacuum cruise was always - yep - vacuum. There should be a vacuum switch on the brake pedal. Find it, and pull the line off it and plug it and test the cruise. My best guess is that's your culprit. Second likely is the speed sender. (Can't tell you much more, theres different kinds...) If you can get the service info, you can also check the the actuator, the feedback pots in the actuator, then the switches, then all that's left is the module.

jayhackett03

wow.

i know that it's getting vaccum to the actuator.

i'll look into the other stuff.

midiwall

SCS is still around... If you don't have an installation manual, I wonder if they can find one laying around?

http://www.scsfrigette.com/html/products/cruise.htm

Flamedx4

They probably can, they are pretty good about stuff like that.