Side Obstacle Detection (SOD) Modules
WARNING: This page is about a different car, the 2015 Lincoln MKS. However, it is still accessible from the selected car via links, so may be relevant.
The BLIS® and the CTA system utilizes 2 modules that have integral radar sensors located rearward of the rear wheel under the rear bumper cover. The 2 modules, SOD-L and SOD-R, are hardwired to the exterior mirrors to illuminate the exterior rear view mirror LEDs.