'95 ABS controller

Every now and then when Im pulling into a parking space or something, usually only happens at crawling speed at full lock steering, the brakes make this horrific noise and the ABS controller and the trac. assist. goes away. I've checked the brakes and they're good but it keeps doing it and its getting more and more frequent. Im thinking maybe a loose wire but I dont know where the controller is to check. Any help would be appreciated. Thanks.