Central locking system

Good day! I trust all of you are doing well.just for my own interest,can someone please explain to me how the central locking system works on most VW POLOs that locks when the car moves,and not with the switching of the ignition.does it has something to do with the electronic coil,I'm just curious to know how this circuit works.I have tried google with no luck.

Thanks in advance

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Do it once,do it right - This means no short cuts. You never get paid twice for having to do the job twice because it wasn't done right the first time.

Road speed, usually derived from a series of pulses from a hall effect switch on the gearbox. A processor reads this and once you reach say 8 miles an hour sends the lock command.
Used to be built into Clifford and I believe nowadays Compustar alarms, they read tach, 3 X idle speed under load.

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Amateurs assume, don't test and have problems; pros test first. I am not a free install service.
Read the installation manual, do a search here or online for your vehicle wiring before posting.

Thank you very much,I am satisfied with your answer.

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Do it once,do it right - This means no short cuts. You never get paid twice for having to do the job twice because it wasn't done right the first time.