Here's What That Button On Your Car's Rear View Mirror Is For

Though not always actively thought of as such, mirrors are some of the most important components of a car. Side mirrors and the center rear view mirror — the longtime home of the weird theory-spawning fuzzy dice – help you see what's coming up behind and to the side of the vehicle. This way, you can better anticipate the movements of other drivers, turn, and change lanes safely. At face value, these are pretty simple elements that don't require a whole lot of understanding to use effectively. However, in the case of rear view mirrors, they have advanced a bit in recent years to include buttons.

If you've been driving around with a rear view mirror featuring a button without actually using it, you might have missed out on a pretty handy feature up to this point. Typically, this button or set of buttons can slightly alter how the reflections in the mirror appear. If your mirror has an automatic mode, it can adjust on its own, but you can also manually switch between daytime and nighttime driving modes. When in night mode, the mirror helps reduce headlight glare from cars behind you, making it easier to see. In an era where car headlights seem to be getting brighter, this is an invaluable tool to be aware of for the sake of your eyesight and safety on the road.

While this is the most common reason for a rear view mirror button, it's not the only one. There's another safety feature that could be built into your rear view mirror.

Rear view mirrors can be a surprisingly versatile safety feature. Not only do they make it easier to see behind you while driving, but as mentioned earlier, some models automatically adjust for different driving conditions and reduce glare from headlights. As it turns out, there's more to the safety features that can be packed into rear view mirrors and utilized with the push of a button. 

Depending on the type of rear view mirror in your vehicle, you could use it to reach out for help in an emergency situation with the push of a button — something incredibly helpful if you don't have access to AAA or aren't familiar with how to use satellite-based roadside assistance services on your iPhone.

For example, if you drive a car equipped with a UConnect rear view mirror from Mopar, you can use the Assist button to get help. Most notably, this button can help you access roadside assistance in the event your car breaks down, you have to pull over with a flat tire, or you otherwise need some form of emergency support. These are typically found in vehicles from specific brands, such as Chrysler, Dodge, Jeep, Ram, and more. Hyundai has a similar offering through its Bluelink system. Its rear view mirrors feature Roadside Assistance and SOS buttons to be used depending on the severity of the situation at hand.

Of course, it's no secret that not every car has such an advanced rear view mirror system. Some lack any extra features at all, simply reflecting without doing anything else. If one feels so inclined, they could upgrade their rear view mirror to one of these more enhanced ones.

If you're working with an older, less-advanced rear view mirror, swapping it out is possible. However, if you want a new one that has all kinds of bells and whistles, you'll have to put in some work. If you want to give it a shot, these are the general steps you'll have to take.

1. Per your mirror's instructions, attach it to the windshield.

2. Disconnect the negative car battery terminal.

3. Determine where the mirror will plug in. Options include the panel where the interior lights are often set near the top center of the windshield or the fuse box to the left and beneath the steering wheel on the driver's side.

4. Remove the necessary panels to access your chosen connection port.

5. For the top panel, feed the wire through the ceiling lining until it comes through the panel opening. For the fuse box, carefully tuck in the wiring along the ceiling border until it reaches the box.

6. Connect the wires to the electrical ports. This step will likely involve consulting the instructions for your mirror and knowing which port is which, inside your car.

7. With all wiring connected, reattach the negative battery terminal and start the vehicle.

8. If everything reads properly on the mirror, reattach the removed panels. If not, there's likely a wiring issue to be resolved.

For some help, it's best to find an exact tutorial for your desired mirror model before attempting the swap. Otherwise, the process might not go as planned.

Rear view mirrors are crucial to modern automobiles that have advanced at an impressive rate. Time will tell what they'll be capable of in the future and if they'll take on any more handy buttons.