Common obd1 cruise control fail points??

Wondering what the common failure points are for the cruise in my 91 Laredo.

Auto trans, 4.0 HO...


It's never worked as long as I've owned it. Not even sure if the 91 has an indicator light for cruise, but if it does, it never turns on.

So what are the common failure points on these. I don't suspect vacuum lines, as the bumper bubble has been relocated up to the firewall, and so there are no breaks in the line at all.

This is the old school one where the switch is in with the blinker knob.

i don't know the difference between the OBD1 and whatever the system is before that, but i have a '90 that i've been trouble shooting for years....
it never worked when i got the heep a few years ago, but the cruise on my (totaled) '89 heep worked fine. so i swapped out all the parts under the hood, swapped brains and got a 3rd brain from a bone yard for more variables.

i have spent hours tracing wires and checking for continuity on every bit of the cruise control system, and everything is fine. all the vacuum lines are new and theres no leaks. applied 12v to all the different little actuators or whatever in the cable control thing that i can't remember the name of.

the only problems i found were 2 of the 4 wires in the blinker switch had broken inside the wire jacket right where the arm goes into the steering column. basically right at the flex joint...

stripped it all back and re-soldered them, and have proper continuity for every function of the controls according to the FSM. but the most i ever got it to do was jerk a few times one afternoon.
this was, i believe last summer when i finally gave up on it. my next step would be to replace the whole blinker/control arm ($30 at oreilly's autoparts in the HELP section)....unfortunately i had already junked my '89 when i found this or i would have taken it from that.

and now that i'm getting rid of my '90 i just don't care, haha.

so, technically not much help for you, BUT, try checking the wires on the control arm *shrugs*