I have put a new battery in my key fob on a 02 vw passat now it wont work can you help ???

Hi,

Please double check that you're purchasing the key fob from either VW or a different brand than the one that gave you the error. I'm guessing the brand that you have is making defective key fobs otherwise, the new fob should have worked.

Thank you.

Your key fob might need a new battery.Check this link out. Programming VW Golf Passat Cabrio key fobs in VW

You are going to need to take a trip to the dealer, it has lost module programming.

try using a scan tool to reset the CPU program in the ECM as it may be corrupted form the long period of no use

2012 means you may still have the original battery in the fob. Test the battery. Take to a local parts store. They have a tester at the counter.

You may have lost programming to the body control module, contact the local VW dealer to scan the system for faults.

I had the same problem...you have to depress the silver button on the gear shifter as if you are trying to put it into drive from park. It won't let you actually press it in all the way...but just press it in as far as it will let you and if you listen carefully, it makes a little sound near the key fob and it somehow electronically triggers a switch that if you pull on it after you hear that sound and within 1-2 seconds of pressing the gear-shifter button, it releases the key fob.

On the driver's side door handle, there is a cap covering the key hole on the right side. On the bottom of the cap is a small ****. Use the valet key to pry it up and off. Then you may open the door, most likely sounding the alarm, so you will need to insert the remote in the ignition to stop the NOISE!!!! Hope this helps. This is how I lock my remote away when I go somewhere to run.

My used 2003 Passat came with both fobs unable to hold a key. I had to break them open to retrofit a loop. These are some great links that I bookmarked. The first one should give you programmin instructions.Good luck!

http://reviews.ebay.com/VW-Volkswagen-keyless-entry-flip-key-remote-users-guide_W0QQugidZ10000000003961176

http://www.keysforvw.com/diy.html

http://forums.vwvortex.com/zerothread?id=1216091

http://www.ross-tech.com/vag-com/cars/vw-remote-matching.html

dealers will reset the codes for you but it aint cheap