How to re-sync keys after charging flat battery??

[mark_le_b]

Hi all

I had to remove my battery (E53 X5 3.0i) to charge it as it was flat.

All back in no problem and car starts etc., but neither key will now lock/unlock any of the doors/boot-lid

Can anybody advise the re-syncing procedure to get the keys to work correctly again?

Thanks

Mark

[JohnnyRob]

Not sure where I found this but it's within a word file I've saved for e53 hints & tips.  Hopefully it'll work -

1. Turn key to position 1 five times very quickly
2. Remove key
3. Hold unlock button then press lock button 3 times, release unlock button.
4. If you have another key do the same button pressing within 30 seconds
5. Turn on ignition to finalise.

[mark_le_b]

Thanks, I will give that a try.

[marksoldx5]

Just worked for me, Fantastic

I had synced my keys without doing the ignition on and off 5 times. This did work, but then both keys lost sync again.

I had repaired one of my diamond shape keys, by using a rechargeable battery.
Ebay item: 252005632983 this one came with the contacts in the correct place for my E53 2002 car.

These cheaper ( Ebay no: 223501825291) ones had the contacts in the wrong place, so I had to faff around and take the metal contacts off the battery as well and after all that it didn't work. So do NOT bother with these, pay the extra and use the other ones.

Mark