2003 Subaru Impreza Owner's Manual - Page 253

Starting and operating CAUTION D The ABS system does not always decrease stopping distance. You should always maintain a safe following distance from other vehicles. D When driving on badly surfaced roads, gravel roads, icy roads, or over deep newly fallen snow, stopping distances may be longer for a vehicle with the ABS system than one without. When driving under these conditions, therefore, reduce your speed and leave ample distance from other vehicles. D When you feel the ABS system operating, you should maintain constant brake pedal pressure. Do not pump the brake pedal since doing so may defeat the operation of the ABS system. J ABS warning light J ABS system self-check You may feel a slight shock in the brake pedal and hear the operating sound of ABS from the engine compartment just after the vehicle is started. This is caused by an automatic functional test of the ABS system being carried out and does not indicate any abnormal condition. The ABS warning light comes on when the ignition switch is turned to the "ON" position and goes out after about two seconds. This is an indication that the ABS system is working properly. When driving with an insufficient battery voltage such as when the engine is jump started, the ABS warning light may come on. This is due to the low battery voltage and does not indicate a malfunction. When the battery becomes fully charged, the light will go out. 7-24