38 problems related to brake electric antilock have been reported for the 2002 Subaru Impreza Wrx. The most recently reported issues are listed below.
Ongoing / intermittent problem with brake pedal going to the floor whenever vehicle runs over a bump, and causes a none stopping vehicle. Vehicle been to dealer on two occasions, and unable to locate cause.
My 2002 supra Impreza Wrx sedan has produced inconsistent and unsafe brake operation over rough/washboard type roads. On a number of occasions while braking in a rough road surface my brake pedal went to the floor and my car kept going. Upon encountering rough road and the resulting actions by the break system I have experienced increased stopping distance. I sent an e-mail to Subaru of America and the the response was to the effect that they were unaware of any such problem. I had the dealer inspect my break system and I was told they were unable to duplicate problem.
During braking on rough surfaces, the abs system significantly reduces pressure to the brakes, resulting in near total loss of braking action. When this occurs, the brake pedal drops significantly and there is no pulsing action. I have experienced this three times. The first incident was approaching an intersection. I was traveling approximately 35 mph, and when I applied the brakes, the pedal dropped several inches and there was little, if any braking action. Luckily, I had a green light and I was able to negotiate the turn without incident. The second time I was traveling on a gravel road. I was traveling approximately 15-20 mph, and as I came around a corner I encountered a truck that was driving in the middle of the road. Again, I applied the brakes without any effect. I was forced to take evasive action and go into the ditch to avoid an accident. After that, I took the car to a dealer. I was able to reproduce the behavior once with a technician in the car. We were driving approximately 15-20 mph and I applied the brakes on a rough section of pavement. The abs pulsed several times, then it stopped pulsing for 2-3 seconds, and then it started pulsing again. During the period when it stopped pulsing, the brake pedal was soft and dropped 1-2 inches. The technician tried to replicate it without success. The technician inspected the system, including checking for diagnostic codes, but could not find a problem.