E320 Electronic Key Not Working

Hi , The spare key for my E320 has been laying unused for maybe a couple of years . When I went to use it recently it would not work , I replaced the two
batteries in it and now it will unlock and lock the car OK but it won't work the ignition . I am wondering if maybe it needs reprogramming , or maybe the infa red light or whatever it is that works the ignition has simply had its day , if anyone has had this problem themselves , or some information on it , it would be very much appreciated .
Cheers
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Usually needs reprogramming if left dormant for a few months... in the UK it's pretty much a main dealer only job...make sure you take all sets of keys for the car when you have it done, so they can all be in sync.

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    I do not believe a 'flat' battery is the problem. The 'valet key' does not have a battery and the car can be started with it. After 12 months without use my remote opening was dead however new batterys fixed that and ignition worked with the dead battery(s).
Dave S (C 250TD Touring UK)
+q wrote:

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