I had a 99 grand am first check your brake fuild. If it is fine disconect the red battery cable and give the computer time to rest if it is still on you may have to take it to the shop could be something wrong with the traction system or the braking system.

You have a bad wheel bearing. very commom on your car.

A common problem with 2000 - 2005 Grand Am's and Grand Prix's was failure of the wiring to the wheel speed sensors. This would cause the ABS not to funtion, as well as traction control, and, mayube even cruise control. One tell tale sign is if your brake fluid level is normal, and the "Brake" warning light has come on as well. First try resetting the ECU and ABSCU by unplugging the battery or fuses for at least 15 minutes. This will clear all error codes from the system. Plug the fuses or battery back in and start your vehicle. The ABS light should remain on for at least 3-5 seconds and then deactivate. In some cases you may here a small click from under the hood (ABS cycle check). Once this cycle is complete the ABS light should turn off. If it does not, take your vehicle to the dealer. Have them check the ABS computer, and/or do an OBD check, and check the wiring on each speed sensor, including the main transaxel sensor which operrates the speedometer and SCV for the radio. You should also do this anyway even if resetting the computer system clears the lights as this can lead to a serios problem if ABS does not function. I hope this helps.