METHOD AND DEVICE PERTAINING TO THE SERVICE NEED OF A FILTER IN A SCR-SYSTEM'S LIQUID SUPPLY DEVICE

摘要

The invention relates to a method pertaining to SCR systems for exhaust cleaning whereby liquid is supplied to a feed device (230) via which it is then supplied to a dosing unit (250) at a consumption point of the SCR system. The method comprises the step of continuously determining cumulative amounts of liquid dosed via the dosing unit (250). Need for replacement or cleaning of a filter unit (F) for said liquid is also determined on the basis of said cumulative amounts of liquid dosed. The method further comprises the step of dosing at least part of the liquid supplied via the feed device (230); and feeding undosed liquid back in a return flow to enable it to be supplied again to said feed device (230). The invention relates also to a computer programme product which comprises programme code (P) for a computer (200; 210) for implementing a method according to the invention. The invention relates also to a device and to a motor vehicle which is equipped with the device.