Replaced battery - now all 3 FOBs won't remotely lock/unlock the doors

[DPDISXR4Ti]

I recently replaced my battery and seem to have immediately lost the sync between all three of my fobs. I can physically un/lock the doors by using the key, so that all seems to work fine.

Do I need to go through the programming process using VCDS or is there some short-cut procedure?

[Cybersombosis]

Try sticking your key in the ignition, then press and hold the lock button on the fob, then turn the key to the on position (do not start the car), then turn to off position. Your fob should be synced again.

[Puddin Tane]

I know this doesn't solve your problem, for which I apologize, but this sort of thing is why I always patch in a 12V source via the OBD2 port when pulling the battery. Do this and you'll never have this sort of problem again.

[old guy]

To re-sync the key fob simply insert key, turn to on position, wait 5 seconds, turn to off position, remove key. Done. (It’s in the manual).

And believe me, I know. I had to re-sync one of my keys probably a hundred times. If you are bored, read this thread for a little entertainment. KEY FOB CRAZINESS

[DPDISXR4Ti]

To re-sync the key fob simply insert key, turn to on position, wait 5 seconds, turn to off position, remove key. Done. (It’s in the manual).

Finally got a chance to try this and no luck at all. Tried it with all 3 FOBs and nothing.

I'm not sure if it makes a difference but I have upgraded to the B7 FOBs and the ...433BB modules. Wait, check that, I've got two B7 FOBs and one B6 FOB.

[DPDISXR4Ti]

Try sticking your key in the ignition, then press and hold the lock button on the fob, then turn the key to the on position (do not start the car), then turn to off position. Your fob should be synced again.

Thank you - this ^^^ worked!

Funny enough, it only worked with one of the B7 FOBs. Then I realized the batteries were dead on my two spares! Looks like it's a CR2025 battery for the B7 FOB and a CR2032 for the B6 FOB.

[EuroxS4]

B7 fob should be a 2032 coin cell battery. Make sure the key part number starts with 8E0 otherwise the key fob will not work and needs to be FCC ID MY4073A.