Two problems related to brake sensor have been reported for the 2003 GMC Safari. The most recently reported issues are listed below.
Our 2003 GMC Safari has had the brakes spontaneously fail while we were driving it at least six times (every couple of months or so) for the past year. Each time, the pedal just dropped to the floor, the "brake" light came on, and we have had to practically stand on the brake pedal to get it to finally roll to a stop. Fortunately it has been at slow speeds each time and we have not caused any accidents yet. We have been to two different dealerships repeatedly and spent over $1000. 00 for various brake system components that are not fixing the problem. We think it is either a booster or sensor issue, but the dealerships will not listen to us and GMC's customer service line has not been helpful either. We are terrified of driving this vehicle but can't afford a new one at this time.
Corrosion has built up on the abs sensors causing them to activate at low speeds. When this happens the brakes don't lock up and at low speeds (less than 4 mph) that means the vehicle takes an extra few feet to stop. On one occasion I almost hit a person and two other times a parked car in a parking lot because the car didn't stop. The problem is intermittent so the dealer could not duplicate the problem and therefore can't fix it. There is a gm recall (#05068) for other like models of gm cars but not mine. So my problem is the dealer can't fix it without a recall and gm won't issue a recall because there hasn't been enough complaints.