Like HowStuffWorks on Facebook!

How Bluetooth Car Stereos Work


Capabilities of a Bluetooth Car Stereo System
Bluetooth car stereos have lots of features, from hands-free calling to video displays.
Bluetooth car stereos have lots of features, from hands-free calling to video displays.
Photo Courtesy JVC

Now that we've got a handle on Bluetooth 101, let's see what it can do in a stereo. Bluetooth car stereos are commonly integrated with Bluetooth-enabled cell phones, and when the two devices are within range of each other, they can communicate in a number of interesting ways. Depending on the particular models in use, it may be possible to make and receive calls without even pulling out your phone or pushing a single button. You can even hear the calls through the vehicle's speakers. Other models may require a few button-pushes, but usually with more ease than plodding through cell phone menus. You may also be able to view other information such as the phonebook, incoming calls and call status on the stereo panel. When the phone rings, the speakers will automatically turn down the volume on any music or movies that are playing while you chat on the phone and resume when the call is over.

Some Bluetooth car stereos can store your phone's entire address book and other contact information; others have built-in phones which copy all the information off your phone's SIM card and take over the functions for calling. Your cell phone is disconnected from the piconet, not only saving its battery power but also providing a stronger connection.

These innovations come almost as much out of necessity as convenience -- at least for people who can't stand being in the car without making a quick phone call. Many places now enforce laws limiting the use of cell phones while driving, and Bluetooth car stereos are one way to bridge the middle ground.

Besides augmenting your ability to connect with the outside world through phone calls, Bluetooth car stereos can also enhance the environment inside a vehicle. Transmitters can be used to stream music from iPods, MP3 players and satellite radio straight into the stereo without creating a mess of tangled cords. Some car stereos can display video on full-color LCD displays, although this usually isn't an option when the car is moving. If you have some passengers in the back who could use a movie to settle down, lots of Bluetooth-enabled car stereos also come with the hookups needed to turn your vehicle into a mobile entertainment center. Connections for other devices like GPS navigators and USB flash drives are among other common fixtures.

And with each passing year, the technology grows and evolves. Comparing Bluetooth-enabled car stereos to cassette-enabled car stereos already seems like a throwback to the Middle Ages, so who knows what the future has in store.

If all this talk about Bluetooth car stereos has you hooked, on the next page, you can read about some of the considerations you'll want to make before you head down to the electronics store.