Knowing the inner workings of your vehicle can ensure you get the most out of its functions. This knowledge can also greatly improve your overall driving experience and even keep you safe. One thing we're often asked here at Simmons Rockwell Subaru is how auto-dimming rearview mirrors work. Here's a simple overview.
Auto-dimming mirrors reduce glare by automatically darkening when too much light from behind is detected. This function allows you to focus on the road more fully. The system works the the use of sensors that send messages to two layers of electricity-conducting glass with an electrochromic gel between them.
One sensor faces forward and is meant to measure light levels. As darkness falls, this sensor sends a message to the control unit of the mirror to be ready to dim. The second sensor points to the rear and detects glare. It lets the control unit know to send an electrical current through the glass, activating and darkening the gel. The mirror's surface returns to normal when lighting lessens, and the current turns off.
