How to Disable the Mercedes-Benz W211 SOS System Using DAS/Xentry?

This is a 2004 Mercedes E320. The owner has been dealing with the annoying SOS inactive code for months. Every 5 minutes or so, the audio randomly cuts out while driving, and the white TeleAid SOS warning error pops up on the instrument cluster.

TeleAid SOS warning error

Solution:

You can resolve this by using MB STAR diagnostic software DAS/Xentry. The specific steps are as follows:

  1. Use MB STAR diagnostic software to access the control unit:

    • Body -> CGW (Central Gateway) -> Control Unit Adaptations -> Read Coding and Change if Necessary -> Telecommunications -> Telematics Service “Tele Aid” -> Change the MOST technology coding from "PRESENT" to "NOT PRESENT."
  2. For pre-2006 vehicles, you will need to use a Mercedes-specific diagnostic system (e.g., SD Connect C6, VCI C6, or VXDIAG VCX SE for Benz) along with Xentry/DAS software. Neither an OBD2 scanner nor Xentry Passthru will work. You will need an actual MB Star device.

Steps in DAS:

  1. Go to Control Unit Groups -> Info and Comms -> Audio, Video, Nav -> Control Unit Adaptations -> Read Coding and change if necessary -> MOST Specified Config -> Telematics -> Set to “NOT PRESENT,” and carry out the coding.

  2. Go to Control Unit Groups -> Body -> CGW -> Control Unit Adaptations -> Read Coding and change if necessary -> Telecommunications -> Telematics -> Set to “NOT PRESENT,” and carry out the coding.

  3. (Optional) Remove the physical control module from the car. You will need to insert a fiber optic loop (available on Amazon for around $10).

Note: Keep TeleAid set to “PRESENT” in the Airbag Module, or you will receive an SRS code. The SRS system needs to output data to the module if it is still in the car.