light next to gas guage

Yes it is Tire Pressure Monitoring warning light. Set your tire pressures to the recommended pressures according to your owners hand book or sticker on your car, with the vehicle stopped, ignition key on, press and hold down the tire pressure reset button (on the left side of the dash just above the hood open lever) hold down the button until the tire pressure monitoring light flashes three times, start the vehicle, the light should go out.

Do the 2 arrows have a horseshoe looking icon surrounding them (that is the cross section of a tire)? This sounds like your tire pressure monitoring system (TPMS) light. You'll want to check your tire pressures and make sure none are low. The sticker in your driver side door jamb should show the required tire pressures. Be sure to check the pressure when the tire is cold to get the most accurate reading. If it came with one, Toyota owner's manuals usually have really good diagrams and information that should help. hope this helps!

simply means Tires need air.