Hi, i have e61 2006, so the problem is that key fob does not lock remotely. I use comfort access to unlock doors and lock them all, works fine. I use key fob to unlock car, also the trunk unlocks fine too. Changed the broken wires in passenger side hinges on trunk lid, no progress (only fixed trunk glass open button works now. Radio, comfort access works well, so I ruled out diversity antenna. Is there a separate wire for remote locking doors..? Or maybe there is a way to check weather my lock button on fob doesnt work? Also tried to reinitialise key fob - no success. Any Ideas?
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Does the fob lock the driver's side door? If no, then it is unrelated to the wiring harness to the back hatch.

Have you tried a second key? If you don't have one that's not a great place to be either.

If you press and hold the lock button on the fob does the alarm go off? This is how a US car works, but it may be different for your car if, for example, it does not have an alarm system.

If unlocking works with your fob, then I'd say the fob electronics are ok and I suspect the microswitch that is the lock button. It may just be clogged with dirt or maybe the contacts are messed up.

This guy will cut a new key for you and send you a shell that snaps together along with a new battery. You send him a closeup of your key and he will cut it. I've used him before and he's very fast. I'm pretty sure he will ship internationally. You may find someone closer. This is preferable to cutting open your key and repairing it and gluing it back together.

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