Umass021

I recently found a 1997 nissan maxima for sale with 93k on it. The guy said after they did the back brakes 1 week later the abs light came on. He thinks it is a sensor but he doesn't know. Does anyone have any idea if the sensors go on these cars and is this problem easy to fix? He also said the brakes go fast on this car is there any reason for it? Calpiers froze up twice.