The vehicle has a battery saver feature designed to protect the vehicle's battery.
When any interior lamp is left on and the ignition is turned off, the battery rundown protection system automatically turns the lamp off after 20 minutes.
This prevents draining of the battery.
Chevrolet Cobalt Owners Manual. Remote Vehicle Start
Your vehicle may have a remote start feature.
This feature allows you to start the engine from
outside the vehicle. It may also start the vehicle's
heating or air conditioning systems. When you start
your vehicle using the remote start feature, the climate
control system will come on and adjust ...