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Message: <blockquote data-quote="Schwepps" data-source="post: 394406" data-attributes="member: 3592">Going OT a bit, but I hunted down this piece I read long ago, that might help us understand why it takes a bit longer for the locks to operate and why multiple clicks are sometimes required:Each remote key works with it's own set of security codes, and it does not care what is going on with another remote key. The remote keys have to go through a separate "initialisation" process. When this is done the car's security unit selects a "code word" for each key (a randomly chosen number from a base of 2 to the 48th.) This code word is transferred to the remote key and is also remembered by the car for that key. Each key has it's own randomly chosen code word.Now each time you hit a button on a remote key the code word is incremented by one number in it's series. So the next time you use that key with the car it is expecting to see the next higher number. Since you might hit a button away from the car it tracks a series of numbers and will resync the key & code if it is within a certain range. If you hit a button often enough away from the car to get outside the expected range, then you will have to hit a button twice before the car will respond - and then put itself back in sync for that key. There is another higher range (1000 strikes) that if you go beyond that the car will not respond and you will have to re-initialise all the remote keys - they then start will new code words again. So essentially the car keeps track of the "code word series" of numbers for "each remote key".</blockquote>

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