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Electrical - Aftermarket Tampering Malfunctions

Date: October 26, 2010

Order No.: S-B-54.21/234a

Supersedes: S-B-54.21/234, dated July 27, 2010

Group: 54

Revision History

Revision Date Purpose

a 10/22/10 Additional devices and pictures added.

- 7/27/10 Initial issue

SUBJECT: MY- All, Models All

Malfunctions Due to Other-Make Installations

Recent attempts manipulating vehicle mileage through the use of third party electronic devices installed on Mercedes-Benz vehicles are being reported.





There are several CAN manipulation devices on the market. Be particularly aware of two devices which are installed in tandem with the instrument cluster or the EIS (Figure 1) and a circuit board which can be installed directly within the EIS (Figure 2).





If vehicle electronics malfunction, control units display implausible mileage readings, or malfunctions lack corresponding default entries; check the vehicle for non-factory hardware. These are often installed in the interior wiring harness of the vehicle. Another example would be the TV enable module for the COMAND APS NTG2 in Figure 3.

Possible malfunctions are:

^ Random unlocking or locking of the vehicle while driving

^ Temporary or continuous hazard warning system activation

^ Sudden mileage increase in the IC

If there is evidence that the vehicle has been tampered with (mileage altering device, aftermarket installation etc) please provide as much supporting documents (pictures, test results, etc.) and send an email with the supporting documents to the Warranty Services Group and request that the vehicle be put on warranty status.

Warranty will determine the correct status to be applied (usually status 8 which requires AOM review before any repairs are performed), file the supporting documentation and add notes into our vehicle master system.

Any vehicle with a warranty status will have an alert box pop up when VMI is run to inform the dealer of this status.

Any malfunctions or subsequent damage to other parts due to the installation of foreign parts are not covered by Warranty. The repair costs should be charged to the customer.