Hi,

sometimes i need to push the set/acc button 10-20 times until the cc works.
And then it often stop working after a few miles.

Itīs a 97 Blazer S10.

Maybe a loose connection? How to check it?

 

Check all of the vacuum lines under the hood, maybe due to low vacuum. Also check the vacuum reservoir for cracks.

Just a start.

 

There are no vacuum lines connected to the cruise control module, i think there is an electric motor which is pulling the throttle.

 

You may need a new stalk or speed sensor.
Any oddball shifts or bouncing of the speedo?

 

The speedo is fine.

Where is the speed sensor located and how to check it?

 

I have the same problem. I haven't been able to track down the problem yet, but the blinker/wiper/cc mechanism and wiring is my first suspect. They're troublesome in all GMs.

Edit: Troublesome may have been a bit harsh. They just don't usually last the life of the vehicle.

 

Its most likely fine if your speedo is not bouncing.
Its on the drivers side tide to the tranny, look on youtube you will find a pic, that aint it.
Check the cable from the throttle body to the cruise control, make sure al is well there.


Unplug every connector you can find from the cruise and soak it with spray electronics cleaner, hardware store, marine store or radio shack.


If this does not work get a cheap Chinese multi from E-Bay.

 

Ok, problem was the cruise control switch in the steering column. Set and accelerate switch worked but off/on switch didnt.

Port A at cruise control module didnīt get voltage because of the off/on switch. I put a new wire with 12v and a fuse to this port and now its like cruise is allways at the on position, even at off position.

To switch the cruise control off i need to tap Set and R/A at the same time or tap the brake pedal. Cruise control is working fine

 

This could probably help a lot of people. Any chance you could snap a couple pictures and make a DIY?

 

I think this circuit diagram will help a lot.

In this case there was no voltage at port A while cruise switch in on position.