Yes, it matters which wire goes where on a light switch. The hot wire should always go to the back, on the side with the brass screw. The ground wire will need to be attached to the screw terminal. If the wires are not installed in the correct manner, the light switch will not work. Additionally, it is important to set up the ground wire correctly, as that provides a safety measure for your light switch and needs to be set up properly. If you are unsure of how to connect the wiring in your light switch, you should have an electrician perform the job for you. To get your light switch replaced, contact us today.