One problem related to brake abs warning light has been reported for the 2002 GMC Sierra 1500. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2002 GMC Sierra 1500 based on all problems reported for the 2002 Sierra 1500.
I recently took my truck off the road to replace the shock absorbers. While replacing the rear shocks, I noticed that the brake pads were worn to less than one eighth inch thick. I then looked at the front brake pads and noted that they had hardly any wear. I understand that the front brakes do 70% of the braking and the rear brakes do 30%. That made my finding abnormal. All the brake pads and rotors were replaced, at the same time, about one year ago. When I prepared to change the front shocks, I noted that the abs dashboard light was on. I was turning the vehicle around at the time and when I approached the garage I applied the brakes and the pedal went all the way to the floor. A few seconds later, I felt the brakes modulating and the pedal was forcefully pushed back up to the at rest position. The truck continued to roll and the brakes were ineffective. I have always believed that a dual (front/rear) braking system was a safety feature. I was incredulous that this was even possible. I feel fortunate that I was only navigating in my yard. I pull a 27 foot fifth wheel with this truck several times a year. I can only imagine the outcome if this event happened on the highway with the RV attached. I found many anecdotal stories that were similar to mine on several websites. As of now, this truck is grounded until I find a satisfactory explanation for this. The brake fluid reservoir was found to be completely full of brake fluid and an inspection of the brake lines revealed no sign of leakage. I have not yet delved into the trucks abs system, but I have strong reason to believe it is defective.