Some times the replacement key will operate the central locking system by synchronizing it to the receiver.

Key in ignition & turn on & then back off.
Hold key in hand, depress & hold lock button.
Press unlock button 5 times (quickly).
Release lock button & depress either lock OR unlock 1 time
That procedure must be done in less than 10 seconds from the time you first insert the key into the ignition switch!

But many times the key will need to be authorized with a scanner

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