1997 Cadillac SRX - STS Stability and or Traction Contol Sy

97 Cad Seville 4 dr. STS: At 62,000, had EBTCM Electronic Brake Traction Control Module replaced ($987) due to stability control system engaging when it was not required. The problem occurred at all speeds and driving conditions (but never due to a skid or lack of stability. All on dry roads etc.).
Worked fine for a while, but the problem has been back for the last 20,000 miles or so. It is an itermittant problem meaning you can drive for weeks without it happening and then it will engage on and off for a week or so and then the problem stops for a period of time again. When the problem 0ccurs, the Stability Engagged warning - 55 comes on and you can hear the mechanism working when you tap the brakes. Some times, the breaks will actually engage lightly, even though your foot is not on the brake pedal. Since I have had the Chip replaced and the problem is intermittant, I tend to think that there may be some sensors that are out of wack, dirty or malfunctioning and sending false signals to the system. I fear taking it back to a dealer for repair as I suspect they will just through another chip in it (another $1,000) when the cause may be in the sensors etc. I'm not qualifed to know.
My question to you is, do you have some thoughts on what the problem could be and are there some things that I could do to try to fix the problem. Short of that, can a repair shop (brakes or electrical) tackle the problem rather than having to take it to a dealer. Also, if it is the chip, is it possible that I could find a chip in the 'Used Parts Network" and if so, is it easy or difficult to get at and replace?
Obviously, I'm trying to stay away from another $1,000 bill with the same results later on down the road. Any advise on the subject would be helpful in stearing me in the right direction.
Thanks.