97 Grand Am GT ABD and TCS light on

For about the past year or so, when ever I drive my car in the snow and sometimes in the rain as well, the ABS and Traction Control light illuminate and I lose both functions. I have had it checked on two occations and nothing can be found. I have also had Pads. Rotars, calipers changed (regular maintenance) but it still did not fix the problem. Anyone have any idea what could be causing this very annoying occurance?

I would check the sensors on the wheels. Since the problem occurs only under wet conditions, maybe water is penetrating and shorting them out or interfering with their normal operation?

I agree have the sensors checked, the traction control and ABS are related, the traction control uses the brakes to control wheel spin. When you get into a situation where a wheel is spinning the sensor picks up on it and will apply the brakes in short bursts like the ABS system does when comming to a stop. I can not recall if there are 2 different sensors for the different systems, But like Degtr says, if there getting wet they may be shorting and sending the wrong info. to the computer.

what is it about the ABS sensors, it is a common problem?