Suitable Urea-water Solution

The SCR system is monitored with regard to refilling with an incorrect medium. This monitoring function starts when refilling is detected. Refilling detection is described in the section on the SCR system.

Effectiveness monitoring of the SCR catalytic converter is used for the purpose of determining whether an incorrect medium has been used. An incorrect medium is detected if the effectiveness drops below a certain value within a defined period of time after refilling.

A reversible fault is set in this case. If the fault is determined in two successive driving cycles, an irreversible fault is stored and the MIL is activated.

In addition, the warning scenario with a remaining range of 200 mls is started.