The brakes appear to work fine, however, the brake warning light and abs light are on.

first check brake fluid level, if it is good you will need to pull the ABS codes to find the problem.

I had a 94 Buick Regal Custom with a similar problem. After about a month or 2 after replacing the Disk pads my Brake/ABS light would come on. Plenty of fluid and plenty of brake left over. I then would replace the brakes again. 2 months later the light would come on. The amazing thing was that I found the culprit, and you would not believe what it was........the alternator. Apparently some how the electrical system wasn't getting enough power to the brake sensors. I have had the problem again since replacing the alternator. Hope this helps somebody!