Dear Tom and Ray:
How does one change the key fob battery in a 2003 Volkswagen Jetta Sportwagen TDI? Does the remote require a special process in order to be recognized by the Jetta after you're done? Cheers! — DeWayne
Tom: No, it's a piece of cake, DeWayne.
Ray: You probably have the old-style, "switchblade" key fob with a blue VW logo and three buttons on it (lock, unlock and trunk).
Tom: Assuming that's the one you've got, all you do is press the button so the key springs out. Then turn it on its side. You should see a small groove about halfway up the side. Take a small flat-head screwdriver, insert the end in there and gently twist to pop open the two halves of the remote. Then pull them apart.
Ray: The section with the key will come off, and you'll see that there's nothing in it, other than the key.
Tom: But don't throw it away. You might want it later.
Ray: Then take the other half of the remote and, with your hands, separate the front from the back. One half will house the circuitboard, and the other half will contain the battery.
Tom: Pop the battery out gently with your screwdriver, and push in your replacement CR2032, 3-volt battery (positive end down), which you can get at any hardware store or drugstore.
Ray: Then snap the whole thing back together. It should require no reprogramming whatsoever.
Tom: If you bought a new remote — like my brother did last summer, after I went for a dip in the ocean with his remote in my pocket — that new remote would have to be matched up to your car.
Ray: And sometimes, with modern electronics, if you leave it without a battery for a long time, it can lose its programming memory. So don't start this process and pop out the old battery until you have a replacement handy.
Tom: But it's a trivial job, DeWayne. That's why my brother never charges his customers more than $475 to do it!
(Car Talk is a nationally syndicated column by auTomotive experts (and brothers) Tom and Ray Magliozzi. Write to them at the Car Talk website.)