Green Light on Rear View Mirror (Confusion Cleared)

Nowadays rearview mirrors come with different useful features. So, it’s not really that surprising to see a green light in the mirror. But before you think it’s just a tacky feature; it actually isn’t.

So, why is there a green light on rear view mirror?

Some rearview mirrors have an auto-dimming feature. This feature dims the reflection of the headlight of the car behind you. It’s indicated by a green LED light on the mirror. That’s why when the feature is on, you see a green light in the mirror. The auto-dimming feature reduces driver fatigue and helps against heavy traffic lights.

Anyways, that was nothing but just a short answer to the whole conversation. Keep reading if you want to know more about these mirrors and their features.

Let’s not roam around any longer, shall we?

What Are The Buttons On My Rear View Mirror?

The buttons on a rearview mirror can vary depending on the make and model of your vehicle. However, here are some common buttons you might find:

Power Button: This button turns the rearview mirror on or off. It is used to control the electrical power supply to the mirror.
Auto-Dimming Button: Many modern rearview mirrors have an auto-dimming feature that automatically reduces glare from headlights behind you. The auto-dimming button allows you to activate or deactivate this feature.
Compass Button: Some rearview mirrors have a built-in compass. The compass button is used to activate or deactivate the compass display on the mirror.

Garage Door Opener Buttons: In some vehicles, the rearview mirror may have programmable buttons for controlling your garage door opener. These buttons can be programmed to open or close your garage door.
Map Lights: Certain rearview mirrors have integrated map lights. These buttons are used to turn on or off the lights located on the mirror.

What Does Green Light On Rear View Mirror Mean?

The green LED on the rearview mirror indicates an interesting feature. This is called an auto-dimming system.

It hasn’t been too long since it’s been implemented in cars. Rather, it’s quite recent. The feature also isn’t anything tacky or that sort. It’s just a simple cool little feature.

So, what’s an auto-dimming mirror?

An auto-dimming mirror absorbs all the light. It happens whenever the mirror senses a high amount of light. It’s possible due to the sensors that it has.

Most auto-dimming mirrors have two sensors. They instantly darken the surface and it starts absorbing the light.

Speaking of auto-dimming mirrors, here are some of my best-recommended picks:

No products found.

You can now choose whichever you like more and get it for you!

When you’re being blinded by the headlights behind you, it creates an effect. In medical terms, it’s called the Troxler effect. When it occurs it affects your visual perception severely.

That’s why companies have come up with this to counter that effect. This way you don’t have to look at super bright headlights.

This glare reduction is done by a method called Electrochromism. This method allows the mirror to darken itself whenever it senses too much light.

Although a little bit more expensive than regular mirrors, they’re absolutely worth it.

How Does An Auto-Dimming Mirror Work?

The way an auto-dimming mirror function is pretty simple. There are a couple of diodes, transistors, and capacitors.

But the most important component is the sensors. An auto-dimming mirror usually has two light sensors. These are called ambient sensors and glare sensors.

The ambient sensor is placed at the back of the mirror. So, this sensor is looking forward all the time. This way the sensor can adjust the mirror accordingly.

Unlike the ambient sensor, the glare sensor is placed at the front. So, the glare sensor is watching everything at the back.

These two sensors are connected to a control unit. This control unit, in turn, is connected to the mirror. The control unit has a 12 volts input.

So, let’s see what’s really happening here-

Let’s say, there’s a car behind you which is a giant light source. The glare sensor picks that up and quickly sends the data to the control unit.

The control unit immediately knows what’s going on and dims the mirror. This is done by sending a very low-voltage signal to the mirror.

But how does the mirror get dimmed?

It’s possible due to having multiple layers in between the glass and the mirror. The mirror has 3 parts in total. The glass, the layers in between, and the mirror.

There are a total of 5 layers. Out of 5, there are 2 conductive layers on both sides. In the middle, there are ion storage, electrolyte, and electrochromic layers respectively.

Since there are two conductive layers, you can apply voltage. When that happens, the ions from ion storage enter the electrochromic layers. This makes the layer super dense.

Because of this density, only a limited amount of light is allowed to pass through the mirror. And that is how you, a driver, see less amount of light.

How to Turn Off Auto-Dimming Feature?

If your mirror dims too much, you may consider turning that off. We don’t recommend that because of obvious reasons.

But if you really have to, then start with getting a torque screwdriver. Move the mirror upwards and remove the screw.

To save you some time, we’ve listed the very best screwdrivers for you-

Choose whichever you like the most to get started!

Now, you can slide the mirror and get it out. While doing this, you’ll notice a plug connected to the mirror.

Since you’ve taken it out, you have enough space to pull out the plug. Simply unplug and place the mirror back in its place.

Finally, if you think there are visibility issues, you can try adjusting the mirror first. But you might want to replace the glass, it can be done. But for this, you’re going to need a replacement first.

You can now choose whichever you prefer more and get started!

Frequently Asked Questions

How does night mode on the rearview mirror work?

If there’s a night mode, it probably indicates an auto-dimming feature. Maybe there are different levels of dimming for your mirror. Activating it might dim your mirror more than it normally does.

Why is my car mirror green?

Whenever you flash a flashlight on the mirror, you may see the green light. This green LED light indicates that the auto-dimming is on and successfully working.

Why do rear-view mirrors have two settings?

Depending on the mirrors, they may have two different settings; day and night. The day setting will turn the dimming off. Because in daylight dimmed mirrors can be a problem. But the night setting will auto-dimming on.

Parting Words

That was all we could gather about the green light on rear view mirror. We hope that was enough to clear your confusion.

Finally, have a nice day!

Author
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Rob Dahm

My name is Rob Dham. I am the founder & managing editor of greaseandgears.com. I am trying to offer invaluable insights and solutions to everyday vehicle-related challenges.