
For those without factory Bluetooth, there are many aftermarket options. One is Parrot. I've seen it advertised on eBay along with a Motorola kit. I've held off, but found some new information this evening.
Check Parrot Kits site for some options.
http://www.parrotkits.com/donotcut.html
Here's the best part.
http://www.parrotkits.com/steeringwheel.html Steering Wheel Parrot Harness-Interfaces
For Audi, BMW, Mercedes and VW
Bluetooth Hands-Free that is as good or better than Factory OEM for a lot less cost!
Works with the Parrot 3000 Evolution and replaces the 3000 Evolution controller - so nothing to mount on your dash - Your steering wheel controls everything. Your car looks completely stock but with one
important additon: Bluetooth Hands-Free!
MERCEDES
Fits 2002-2007 C-Class, 2004-2007 CLK, 2002-2007 E-Class, 2005-2007 New Style ML, 2002-2007 SL, and 2002-2007 SLK
Does Not Fit the older ML or the S-Class
How to tell which of the follow 3 kits to order? Simply pull your radio and match up the connector....
Steering Wheel Interface for Mercedes with the 145 Style Connector - Complete Kit
$174.95
Steering Wheel Interface for Mercedes with "145" Style Connector - Complete Kit. This radio is usually in cars with the Audio 5, 20, 50 and Command NAV. The plug at left is included and interfaces with the SW100C Steering Wheel Controller shown below it. Just add the Parrot 3000 Evolution to your order if you don't already have one. Professional Installation is recommended. This product has a 30 Day Money-Back guarantee (less S&H) if you are not delighted. **NOTE: Before ordering any of the above harnesses, please verify that the plugs at the back of your radio match the plugs on our Before ordering any of the above harnesses, please verify that the plugs at the back of your radio match the plugs on our adapters. If your car has a remote amplifier (JBL, Bose, Mark Levinson, Harmon Kardon, Rockford Fosgate, etc - DO NOT ORDER one of the above adapters unless compatibility is indicated. We now have special models for amplified Mazda, Volvo and Honda vehicles - please write. The QCJBL-1, QCGMCSS-2P, QCFCSS-1P, QCFCSS-2P and HBBH-1 adapters work fine with amplified vehicles