This has been generously passed on to my readers as a public service by CNET's Brian Cooley May 29. Thanks Brian.
The owner's manual of any modern car is a festival of disclaimers. Your
satisfaction with seat belts, child seats, gas mileage, and even the car's
likelihood of outlasting its lease all come with exceptions and those pesky 
exclusions. So it should be no surprise that most Bluetooth-equipped cars
have a little note Regarding That Wireless Type Technology. The warning
suggests that you verify your Bluetooth phone's compatibility with the
car's Bluetooth system. Huh? My PC needs no such disclaimer for its USB
support nor does my Wi-Fi router for 802.11g compatibility. And even so,
exactly where and how am I supposed to verify that my Bluetooth phone and
my Bluetooth car will like each other?



Bluetooth revolves around two sets of specifications. One defines the
radio frequency (RF) portion, the actual Low-Frequency radio that sends
information back and forth. The other specification is a complete set of
instructions called profiles that allow Bluetooth devices to accomplish
certain tasks over the network. These profiles cause the headaches.

The Headset Profile was the first Bluetooth profile that supported
Hands-Free calling by connecting a phone to a headset. It has no
accommodation for fancy functions such as dialing or on/off hook control. 
It's just a dumb little conduit that moves audio back and forth.

Then came the richer Hands-Free Profile, which is the technology installed
in most cars today. It took the Headset Profile's ability to move audio
back and forth, then added voice recognition, on/off hook control, and
some information transfer, such as call duration. Yet while carmakers
jumped on the Hands-Free Profile, many Cell Phones run the older, simpler
Headset Profile. AND this disconnect can leave you in the irritating and
costly position of having to buy a new phone to go with your new car.

Mike Foley, executive director of the Bluetooth Special Interest Group
(SIG), estimates that 90 percent of cars will have Bluetooth long before
90 percent of USA cell phones. "This is simply because a car is a much more
expensive product and can absorb the cost of the Bluetooth solution a lot
more readily than a $49 phone that a carrier ends up giving away with
activation," he said. So the rather glacial car industry is arguably
savvier about Bluetooth than the wireless phone business that helped
invent the technology in the first place.

Now, while this is just sounding Manageable, let's now look into the future.

More cool innovations, more annoying incompatibilities...
Car companies want their in-dash Bluetooth system to free you from looking
at your phone for ultimate functionality and safety. But as things stand
now, most Bluetooth-equipped cars require you to glance at both your phone
and the in-dash LCD. The car's display typically shows the dialed number,
as well as call status and duration, while your contacts and the
keypad, which you may need to use for touch-tone services, are all on the
phone. It's a hodgepodge of interfaces and distractions that's for sure.

Enter cars such as the 2006 Audi A6, which offers a Bluetooth system that
uses a new Phone Book Access Profile. It lets the car import your mobile's
call data as you get into the car; missed calls, favorites, recent calls,
and so forth all get populated into the in-dash LCD. Eventually, your
mobile's entire phone book will be transferred to the car, once the
in-dash memory is large enough to support the ever increasing capacity of
today's smart phones. And the Bluetooth SIG tells us to look for BMW and
Toyota/Lexus vehicles to sport phone book access soon, as the technology
is being baked into an official spec.


Pushing the Bluetooth standards:
As an industry Automakers look to be the first organize effort to lead with
the Bluetooth 2.0 stands. Some carmakers are using an even more ambitious
Bluetooth strategy involving what's called the SIM Access Profile. With
this Bluetooth scheme, your vehicle has its own built-in phone that
instantly copies the GSM SIM card info from your mobile when you get in
the car. It then disconnects your mobile from the network and takes over
the connection. When you make calls, they are conducted entirely from the
car's built-in hardware; your mobile phone is just a dead lump of silicon
until you get out of the car. The benefits of this scheme include never
having to charge your phone in the car or worry about it dying, and a
built-in car phone can use an optimized high-gain antenna and heartier RF
power levels. The end result is a premium communication system.

With all these advancements, buying a car with a Bluetooth system is going
to be a little like buying a PC in the '90s--something new is always just
around the corner. Still, go forth and buy that new car; even at its most
basic, the in-car Bluetooth hands-free systems are really very cool. If
you're buying a new car, take those few minutes while the salesperson
"checks with my manager to see if he's willing to lose money by selling
you the car at that price," and head over to the service desk. Ask them to
check if your phone works with that specific car, and have them run off a
copy of compatible phones, especially if you're going to buy a new phone
soon.