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Keyless Entry - Won't Unlock At First Attempt

Unlocking via radio remote control inoperative on first key actuation

Topic number LI54.21-P-049185

Version 1

Design group 54.21 Control modules/modules

Date 03-25-2010

Validity Model series 164+251 with SA code 800 up to production date 31.03.2010 or older vehicles that have been flashed with software release 09/11-00 (A1649022500).

Reason for change

Reason for block

Complaint:

Some vehicles occasionally or constantly cannot be unlocked at the first attempt. The customer must then operate the remote control key a second time.

Cause:

Due to a timing problem between the rear SAM and the radio signal receiver, the first radio signal can be lost. The vehicle is unlocked only on the second actuation of the remote control key.

Remedy:

Flash the rear SAM using SDS version 03/10 or higher.





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