One problem related to brake light on has been reported for the 2003 Toyota Matrix. The most recently reported issues are listed below.
The contact owns a 2003 Toyota Matrix. The contact was driving 40 mph when the brakes were applied and the vehicle spun around four times. The contact stated that the ground was dry and there were no road hazards. The contact merged onto the shoulder for about twenty minutes and then drove home. The vehicle was not taken to the dealer. The manufacturer was notified and a claim was filed. The VIN was unavailable. The failure mileage was 24,000. Updated 09/27/11 the consumer stated she applied the brake very lightly and the vehicle went out of control. It appeared either the brake locked or the accelerator locked. Updated 09/30/11.