My cruise control doesn't work?

Cruise control button on steering wheel stays illuminated constantly (in off mode it has a dim illumination or sometimes flashes rapidly). The "CRUISE" indicator on the dash does not light (except for the startup process, and goes out with all other dash indications). I have power up to the module, and the ground at the module tests good. Now I have replaced the switch (to no avail) and I got a used CC Module at a used parts place, switched it out and it still did not work. The speedometer works just fine, so I'm thinking the VSS is alright. I'm out of ideas. What else?

No the Cruise Control will not work at all, and the "cruise" indication on the dash will not illuminate. Interestingly, when I disconnect the harness from the module, the light on the steering wheel switch begins to work normally (Light completly out on off, and light on when pushed on).

I've been working with a diagram. To date all wires have continuity and power from switch to module. Transmission was just re-installed due to a rebuild. The speedo works correctly, thus leading me to believe the VSS is alright. I tried another module, and steering wheel switches and nothing seems to be working. The on/off switch glows all the time, except when it's in the off position it has a faint glow or flicker. The "CRUISE" indicator on the dash only lights on startup as it should be goes off and will not light at any other time. Since I bought a used module, Ive wondered if that had the same problem and was not a good unit. I've seen this same problem described in a number of different Google searches, but never a solution/repair.

Unlike previous Buicks I have owned, the cruise control on this one varies +/- 3 mph. Older Buicks maintain +/- one- half mph. What has changed and what can be done to fix it, other than driving a foreign model? I have been told that any GM car produced after 2000 have this undesirable trait.

I had this to the shop and they said the cruise control was stuck and it was repaired 2 months later and it is doing it again so this time I have unhooked the cruise control but it still runs fast sometimes turning the motor off and resarting helps but lately that is not working. Could someone give me an idea of what needs to be checked. Thanks

The first thing to check is. Make sure that there are no vacuum leaks.

There are no vacum leaks, bought a code red reader it shows the tps sensor is bad, but when tested it tests good. Could it be the wiring harness to the sensor?

Cruise control stopped working last few days. Have no idea why

The horn does work and no airbag light on, After I left the message I drove the car again and noticed that the rpm would hold on cruiser control but would slow down on hills and not recover the set speed.
My first question would be is this common.
Next question is how I diagnose or check to find problem.
Thanks

Hi, My Buick cruise control box is making a whinning noise. Sometimes loud.I put my hand on it while engine is running to feel the vibration.I never use the cruise but turning it on or off does not affect the rough whinning. The box I am talking about is the square black box attached to the cruise control unit. I unplugged it, remove vac hoses etc but no change to the noise. Can I just disconnect it somehow and make it non functional? Thanks