2003 Oldsmobile Alero Owner's Manual - Page 135

The Enhanced Traction System warning light may come on for the following reasons: If you turn the system off by pressing the ETS button on the center console near the gear shift lever, the warning light will come on and stay on. To turn the system back on, press the button again. The warning light should go off. See Enhanced Traction System (ETS) on page 4-9 for more information. If the traction control system is affected by an engine-related problem, the system will turn off and the warning light will come on. If the vehicle is driven on an extremely rough road, the warning light may come on momentarily but will go off again when the vehicle leaves the rough surface. Enhanced Traction System Active Light If your vehicle has the Enhanced Traction System (ETS), this light will come on when the system is limiting wheel spin. LOW TRAC Slippery road conditions may exist if the Enhanced Traction System active light comes on, so adjust your driving accordingly. The light will stay on for a few seconds after the Enhanced Traction System stops limiting wheel spin. The Enhanced Traction System active light also comes on briefly when you turn the ignition key to ON. If the light doesn't come on then, have it fixed so it will be there to tell you when the system is active. If the Enhanced Traction System warning light comes on and stays on for an extended period of time when the system is turned on and the parking brake is fully released, your vehicle needs service. 3-30