Hey all, I'm sure you've probably beaten this subject to death, but my 2003 Bonneville SSei has been "acting up" for over a year now. I've taken it to three different mechanics. They ALL say they are unable to duplicate my complaint!!! I simply CANNOT believe this. All I have to do is drive down the road a few miles and it starts. The problem seems to be in the antilock braking system. It doesn't seem to matter how fast I'm going. The car suddenly feels like the brakes are engaging. This happens a few times, then the "service stability system" light comes on. This is especially annoying when I have the cruise control on. It kicks off. Also, the brakes don't "catch" right away at times when I come to a stop. Unfortunately, this problem is intermittent???? Seems to go away after I'm on the road for a while on long trips, seems to go away for an entire day at times. So far, the mechanics have changed out my steering column TWICE, then sent me home saying it is fixed. Am I going to suddenly skid off the road, with my brakes totally locked up?? Any information would be appreciated, so I can tell the Pointiac dealer mechanics!!!

Did they replace the entire column?! That warning is generally caused by the steering position sensor, which is attached to the steering shaft. The second cause is a bad wheel speed sensor, which can then activate the brakes. Perhaps the shops where you took is do not have a scanner capable of reading the systems involved. A scan at the dealer should be able to find the problem quickly.

I found this posted in the the wrong topic... here'* her reply:

If your brakes are not stopping properly, or locking up at the wrong time, it would be a good idea to get to it soon. Just tell the dealer the problem you are having, and they will likely run a scan which should pinpoint the problem. Lets see what the scan says before replacing parts that may not be bad.

my car has been doing the same thing for a couple of months from doing research i have been informed that it could be a steering wheel position sensor or a wheel speed sensor i know what you feel like it is very annoying and sometimes can have u nervous when the brakes dont grab right away

A temporary fix is to pull the ABS Buss out in the fuse box in the engine compartment. You will get several lights on the dash ABS, Brakes & Trac off as all of these will be disabled.
It is completely safe but keep in mind you will have NO ABS or Traction Control. The good side you also wont have your brakes coming on by surprise .
I drove mine like this for almost a month before I could scrape the time & money to fix it.
Mine ended up being the front left wheel bearing was shot & causing it. Replacing it solved the problem.
Being that each wheel has a sensor on it it could be any of them or even a couple causing your problem.
You can check the bearings yourself by jacking the car up & checking for play in the wheel.
Grab the top & bottom of each tire & try to rock it in & out. If you feel any play or excessive movement your bearing is worn. Or if your not sure stop by a local alignment shop & see if they will take a look for you. Any competent shop will (should) be able to tell you if & what is bad.

Get her to a Pontiac dealer quickly. You will pay a little more but they will do it right.
NEVER SUGGEST TO A SHOP WHAT YOU THINK NEEDS REPLACING. That is pocket book suicide. Tell them your symptoms as clearly and as detailed as you can., and also what you have had done to it. Take them your past receipts. They will take it from there, starting with a scan. You'll then be fine.

This may be a far fetched band-aid for the situation, but costs nothing to look at....
As mentioned, the wheel sensors can involved in the service stability system error. Since these are electrical sensors and there are connectors at each wheel, pull each connector and inspect for corrosion. If the weatherpak connector has let in moisture, perhaps there is corrosion on one of the connectors and that could cause an intermittent problem. If you find corrosion, clean the connector and see if the problem goes away temporarily (day or two). If it seems to fix it, then you'll only need to replace the weatherpak connector and that would be a simple fix.
Just a thought. Sometimes somebody lucks into a simple inexpensive solution (it'* just never me)

Dan