Why does Android Auto Wireless use both Bluetooth and Wi-Fi?

You get in the car, turn it on, and your phone simply connects to your entertainment system. Wireless Android Auto launches automatically on the dashboard and you’re ready to go. No cable. No need to try to plug anything in. You don’t even need to take your phone out of your bag or pockets. But here’s something most drivers don’t realize: Android Auto’s “wireless” experience actually requires running two separate connections at the same time: Bluetooth and Wi-Fi.

Why both? It’s a good question and the short answer is that neither technology can do the job alone.

Bluetooth handles two specific tasks when it comes to wireless Android Auto: the initial handshake between phone and car and hands-free calling. The handshake is the starting point of the whole process. Bluetooth, as a technology, is energy efficient and low consumption, so your phone can search for your car’s system in the background, pair the two, and exchange the necessary credentials to initiate a Wi-Fi connection. The only thing you need to do is turn on your car.

Handling hands-free calls is the second job of Bluetooth in your car. Android Auto routes audio through your car’s speakers using hands-free protocol. If you turn Bluetooth off during your ride for any reason, it simply cuts the connection. For these two reasons, you cannot run Android Auto wirelessly without Bluetooth.

As mentioned, Bluetooth also initiates Wi-Fi. So why does Android Auto enable Wi-Fi? Because Bluetooth achieves a data rate of around 2-3 Mbps. That’s enough for audio alone, but certainly not enough to stream a high-resolution map interface, audio and touch inputs.

Once the Bluetooth link is complete and your device is paired with your car, your phone connects to a local peer-to-peer 5GHz Wi-Fi Direct network. This is where the magic happens. Wi-Fi Direct provides the bandwidth to handle everything else, from the user interface to high-quality audio from your streaming services to sensor data (GPS details, odometer, on-screen touch inputs, voice commands, ambient light, and more).

Google’s Android Auto developer documentation clearly states that the 5GHz Wi-Fi requirement is strict because standard Bluetooth doesn’t have the bandwidth needed for continuous video projection. This is also the reason why older phone models without 5GHz Wi-Fi support simply cannot run Android Auto wirelessly.

Many vehicles (mine included) only support wired Android Auto. Fortunately, there are many dongles available for purchase, such as the Carlinkit, AAWireless, and the Motorola MA1. These bridge the gap using the same Bluetooth and Wi-Fi logic, with just one extra layer.

You plug this little dongle into your car’s USB port and it mimics a wired smartphone. The dongle then pairs with your phone via Bluetooth, establishing a data connection. Your phone then drops the Bluetooth data link and connects to the dongle via 5GHz Wi-Fi Direct before translating that Wi-Fi stream into a USB signal. As far as your car knows, you are working with a standard wired connection. It’s a simple solution that won’t cost you a fortune.

Using Android Auto wirelessly is certainly convenient, but it has some drawbacks. First, Bluetooth and Wi-Fi should remain enabled, as turning either one off breaks the connection. Maintaining an active 5GHz Wi-Fi connection in addition to GPS and Bluetooth can definitely drain your device’s battery. Additionally, if you are using a dongle, it may add connection delay. You’ll also need to have a phone with 5G capabilities and running Android 11 or newer.

Ultimately, wireless Android Auto works so well because Bluetooth and Wi-Fi each handle the part of the job they’re best suited for. When you know what’s going on behind the scenes, it can seem complicated, but the result is worth it.