cruise control module

Why bother with fixing it?

Your foot can easily handle the task and have greater control of the speed which will result in better fuel mileage and much more stable speed since you can do something that cruise control cannot.. Anticipate the hills BEFORE you get there and lightly apply fuel BEFORE you start losing speed.

I tried cruise control once and noticed that when I came to any hill, it would wait until you lost a preset amount of speed then GUN the throttle to make up for the lost speed.. Might work OK with a lightly loaded car with bunches of excess HP and TQ, not so much with a heavy load like a RV that does not have excess HP and TQ for the load.

28+ yr old vehicle is pretty darned old, most parts have been taken off the books, off the shelf, off the market and often destroyed after a vehicle is 10 yrs old so you are 18+ yrs late to the party.

Troubleshooting can be a bear, sometimes design is changed midstream of the year or you might get real lucky have one that was built for one model year and nothing else fits or works. You really have to have a pretty good understanding of how your specific cruise works mechanically and electronically in order to troubleshoot without shotgunning parts at it.

Yup, a number of things can cause inoperative cruise controls.

That is why I asked about what troubleshooting lead to the diagnosis of bad module.

Improperly adjusted brake light switch can cause issues.

What BRAND and if you know, what model cruise is it?

Bendix?

What troubleshooting have you done to determine that it is the CC module that is bad?

Moved to Tech Issues forum from DIY.

a faulty speed sensor can also be a common problem.

That’s really old...28+ years...for replacement parts.

I don't have an answer but if all else fails you might check out dakotadigital. They make an aftermarket cruise control. I don't know if it would integrate with your switch, but might be worth taking a look at. Scroll down the page for the cruise controls.

Link

Are you sure it isn't the actuator instead of the module? (Or are the they same assy on that year?)
At any rate, they like to develope a hole in the rubber diaphragm.