03 passat key/ fob not working battery ok

try the spare key fob and then a fresh battery in the fob.
many auto parts stores will test and change the remote for you too.

Be sure to use the correct battery, properly in place, clean the key contacts , See owner's manual for additional information.
There are specialized locksmiths for car keys

Replace the battery in the key FOB anyway.

I recently changed the battery on my key fob for my ssanyong rexton. I then did the following for the key fob to make it work. 1. Enter vehicle and close all doors.

2. Put seatbelt on (or clip it into the buckle) to shut the warning buzzer off.

3. Put key in ignition, turn to run position but don't start it.

4. Press and hold both buttons on key fob until red light on fob stays on. Then let go of both buttons. Then pressed the alarm button then the panic button, somthing like that. To be fair the button sequence after the red light came on is a bit vague. The alarm was blaring so i was happy when it just stopped.

You are going to need to check the power lock control moduel on the inside of the door panel. If the FOB appears to be working but the doors are not unlocking, you need to check this. I would also replace all fuses that control the locks. If both of these devices check out ok, you may need to replace your FOB. To check your power lock control moduel, manually lock and unlock your doors by pressing the lock button on the inside of the door. If it does not work, it is either the fuses or the power lock control moduel. If it works, your FOB has gone bad. Hope this helps! Please rate 4 thumbs up!

Does the battery need changing on the key fob?
you can check by using you'r mobile phone cam & pointing the key fob (ultra violet bulb) at the lens when pressing the button, you should see the light flashing on the key fob looking through the camera, you can use any camera, most of them will see the light as it's out of our sight range but cameras pick it up.
If not then unscrew the key fob & split it carefully (use an old credit card not a knife or screwdriver) & change the battery.
If the fob work's then the problem is with the receiver, usually up by the rear view mirror.
Hope this help's !

Was it working before and it just stoped working? Either its not programed to the vehicle or the unlock button is bad. the buttons do wear out over time.

I'm more familiar with Range Rovers and Saab's when it comes to key fobs but if you changed the battery you have to re-program the key fob. If you do not have an owner's manual that can take you through the steps you might want to try: push and hold the lock button on the key fob, put it in the driver's side door and turn to lock. With the button still depressed turn back to open, remove the key and release the button. If this doesn't work check any and all fuses associated with your system and last but not least you could take it to a dealer. Good luck!

1....ensure the battery in the "Key Fob" is OK............Press either Lock or Unlock button for more than 1 second, the lamp on the fob will light if OK. Change battery if it does not illuminate! 2.....if battery on fob OK.......Re Syncronise the key fob to the car by:.... a brief press on either button twice and within 30 seconds turn Key to position 2 on the ignition lock
Hope that fixes it...let me know?

if you hav a remote control key &yr car wont respond . change key batrrey &contact dealer if still dont work for software