The light indicates a low air pressure in one or more (including your spare) of your tires. Recently temperatures have dropped at night causing the air in your tires to contract, lowering the tire pressure. If the pressure lowers enough, it will trigger the Tire Pressure Monitoring System (TPMS) to turn on the light alerting you to have them checked.
Make sure you’re driving on the safest tires regardless of any temperature changes by letting Camarillo Car Care perform a fast, convenient inspection if your tire pressure light is coming on. Most of the time it’s due to the chilly weather, but when it comes to vehicle safety it’s better to be safe than sorry.