what is sgs
I am not familiar with the SGS button on the Chevrolet. I do know that an STS button is the activation button for the StabiliTrak System which is a skid control system. But again, not familiar with the SGS system. What kind of Chevrolet you have?
Found it! The SGS button in Chevrolets means "second gear start." The reason that you would want the car to start in second gear would be to prevent the wheels from spinning incase you find yourself in inclement weather such as rain or snow.