The rearview mirror heating switch on the Buick Verano is located directly above the air conditioning fan speed knob. This switch is labeled "REAR," and turning it on activates heating for both the upper and lower rearview mirrors as well as the rear window. The yellow light indicates that the heating is on, and the light turns off when the heating is deactivated. The heating function will automatically turn off after a period of operation. Rearview mirror heating is particularly useful in rainy or snowy weather. When activated, the heater behind the mirror quickly warms the surface, gradually removing rain or fog, eliminating the need for the driver to manually wipe the mirrors and reducing driving hazards. How to use the rearview mirror heating function: There are generally two ways to activate the rearview mirror heating function. One is combined with the electric rearview mirror adjustment knob—simply rotate the knob to turn it on. The other is located on the air conditioning control panel—press the heating button to activate it. No manual angle adjustment is needed, as the driver's side has a dedicated control button. Principle of the rearview mirror heating function: After pressing the button, the electric heater behind the rearview mirror glass rapidly heats up to a fixed temperature within a few minutes, typically between 35-60 degrees Celsius. The heat is then distributed across the left and right rearview mirrors. As the temperature rises and evaporation occurs, water droplets on the mirror surface gradually shrink, and fog slowly dissipates, effectively defrosting and demisting the mirrors. However, in heavy rain, the effect may diminish and become less noticeable. Precautions for using the rearview mirror heating function: The principle of rearview mirror heating involves electric heating wires embedded in the mirrors, which consume a significant amount of power. To avoid draining the car battery, ensure the vehicle is running when using this function. Avoid activating rearview mirror heating while the car is stationary to prevent insufficient battery power for starting the engine. Other methods for defogging rearview mirrors include: Opening windows for air circulation: Crack open the side windows slightly to allow air exchange between the inside and outside of the car, reducing the temperature difference and gradually eliminating fog. Adjusting the car's air conditioning to the appropriate setting can also help, as blowing warm air aids in defogging.
