en-us https://www.intensedebate.com/users/695986 Comments by HunanNature http://biggovernment.com/bbarr/2009/10/26/cool-cars-guaranteed-to-make-you-hot-under-the-collar/#IDComment40700026 Factory installed GPS and Onstar use external antennas and are not dependant on radio waves penetrating glass. Bluetooth phones use the automobile's cell phone. Factory and dealer installed cell phones use external antennas also. Mon, 26 Oct 2009 14:27:02 +0000 http://biggovernment.com/bbarr/2009/10/26/cool-cars-guaranteed-to-make-you-hot-under-the-collar/#IDComment40700026