2003 Cadillac CTS Owner's Manual - Page 181

Fuel Level Low This symbol appears with the Fuel Level Low message. Headlamps Suggested This symbol appears with the Headlamps Suggested message. When this message appears on the display, it means that your vehicle is low on fuel. You should refill the tank as soon as possible. A single chime will sound when this message is displayed. This message will appear when the amount of available light outside the vehicle is low and the exterior lamp control is off. This message informs the driver that turning on the exterior lamps is recommended even though the DRL are still illuminated and it has become dark enough outside to require the headlamps and/or other exterior lamps. This message will also appear when the windshield wipers have been on for more than six seconds and the exterior lamp control is off or in the parking lamp position. 2-113