Pontiac Repair: Pontiac brakes, rear wheel speed, brake warning light

Question
My daughter has a 1999 Grand Am SE and has complained about the anti-lock brake warning light and traction light coming on in her car.  Had not worried to much about the warnings but her left rear wheel has started to have some brake noise.  Have taken the wheel off and looked at the pads and can not see anything wrong.  She called yesterday and said her brakes were working funny.  On a rainy street it felt like she was on ice.  Do you have any suggestions of where I should look to fix this problem?  

Thank You

Answer
It would be nice to know what ABS codes are stored but without that, my first guess would be that it may be a left rear wheel speed sensor code and the noise may be from a worn left rear wheel bearing (the bearing and sensor are part of the hub assembly). An easy way to check this is to raise the left rear wheel off the ground and try to move the wheel left to right or up and down there should be no movement felt. If you can try to get your computer scanned for codes this would help a lot. Let me know the results.