Why does the cruise control light stay on when the vehicle when it's running?

The cruise control light remains on while the vehicle is running because the system is engaged and ready to maintain a set speed. If the light is illuminated but the system isn't actively controlling speed, it may indicate a malfunction or an error in the cruise control system. Always refer to the vehicle's manual for specific troubleshooting steps or seek professional assistance if the light persists without the system being used.