When the "LOW FUEL" light comes on, you have less than 2 gallons (7.6 liters) of gasoline left. You should refuel your vehicle immediately.
As a bulb check, the light will come on when the ignition key is turned on, and then go out in about 3 seconds. You will hear for indivivual chimes if this light turns on while you are driving.
If the fuel gage system detects a problem, the "LOW FUEL", light may stay on even after refueling. If this occurs, see your Saturn Retailer for service.