Have you tried a fresh battery in the remote and confirmed the problem does not originate there?

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Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)

Its a brand new OE IR remote, does the same thing with my old remote. Just started acting up last week. Trunk, and mirror receiver work fine. Door will work on occasion.

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Dennis
2006 E320 CDI Black/Black Leather. Nav, HTD Seats HK stereo 32000 miles.
2000 VW Passat 1.8t 300,000 miles as of Dec 09, 2009 original owner
1997 E300d Silver 300,000 miles As of Jan 05, 2010
3rd owner SOLD

My response was really aimed toward post #1. If the battery is low on juice it may not be capable of communicating sufficiently with the door to activate the lock.

Replacing it is a cheap first step.

__________________
Terry Allison
N. Calif. & Boca Chica, Panama

09' E320 Bluetec 77k (USA)
09' Hyundai Santa Fe Diesel 48k (S.A.)