I was reading the manual and came across a section that stated that cell phone use, without using an external antennae, will damage the vehicle's electronics. I know I'm behind the times, but I'm trying to catch up. What kind of external antennae is needed? is this for a "car phone" or the average "cell phone". I use my cell for work and being on call often...don't want to mess up the car before the motor is broken-in.