Jorge,

You buy a new antenna, and install it. A 16mm wrench to remove the hold down on the fender, remove the hold down, turn the radio on and when the antenna gets almost all the way up grab it and pull up, slow and steady extracting the plastic gearing attached to the antenna. To insert the new one push the white plastic gearing down into the whole with the gearing facing forward, this can be tricky cause it's currled up, try to streighten it as best you can especially at the bottom. When you have it semi-engaged in the motor (you can kind of feel it drop in just a bit) turn the radio off and the motor will wind up/pull down your new antenna. If it doesn't retract all the way, push whatever didn't retract down until the little ball on the top is even with the 16mm hold down that I forgot to mention need to be put on after you retract it. Now all you do is cycle it a few times and you just saved 1 hour labor at most dealers. I don't know what they cost exactly, I think the dealer price is around 37-48 dollars.