One problem related to brake sensor has been reported for the 2002 GMC Safari. The most recently reported issues are listed below.
When backing out of garage brakes failed and the pedal went all the way to the floor. Dealer told me there was no brake problems, but could be abs sensors rusted or had dirt build up. The dealer cleaned abs sensors and sprayed a rust inhibitor on sensors and hubs , and said they hoped this would solve the problem. If problem persists to come back.