Harness is a direct PlugNplay with no wiring modification of any kind. Installs directly into the body harness inside the front passenger side fender well, behind the front side splash guard. Harness will allow your DRL to work as normal during the day but also cause them to turn on with your headlights at night. This allows for the use of all lights at the same time at night. (Headlights, DRL, and Fog lights.)
   * Please choose whether your car is a ZL1 or not when ordering as the ZL1 harness is specific to the model and a non ZL1 harness will not work.