Service Information: Rejection of warranty and goodwill claims for unapproved modifications to the exhaust aftertreatment unit

Please note that consequential costs, resulting from non-approved adaptations or modifications to the exhaust aftertreatment unit, may not be settled through the warranty or goodwill channels. These costs must be borne directly by the body manufacturer or the end user responsible for making the modification. An example worthy of mentioning here is that of modifications to the sensor system for the exhaust aftertreatment unit, and any costs incurred for inspection findings, repairs, replaced parts etc.

If, by contrast, the vehicles are modified as part of a so-called "single invoice transaction", a professional modification of the sensor system is then assured so that no negative effects can be expected with regard to warranty or goodwill approval.

Example of a non-approved modification to the sensor system
In such an instance, the NOx sensor control unit input for the exhaust aftertreatment unit (A70) and the exhaust pressure sensor upstream of the diesel oxidation catalytic converter (B37) is moved from the previous position to the front of the exhaust aftertreatment unit (1) on the upper side of the exhaust aftertreatment unit. Whereas at the original position an appropriate level of protection against heat was assured, both devices can now be expected to suffer damage through heat radiation and vibrations.

W49.20-1185-81

Information on conducting changes to the exhaust aftertreatment system

All information that is to be observed when changes are made to the exhaust aftertreatment system, is described in extensive detail in the Bodybuilder Portal (https://bb-portal.mercedes-benz.com/portal/index.php).