| 摘要 |
<p>A method for cleaning an SCR system, wherein reducing agent is supplied to an exhaust flow upstream of an SCR catalyst (260), NOx contents of the exhaust flow are determined upstream and downstream of the SCR catalyst (260) and reducing agent crystals are removed by a high-temperature procedure. The steps are determining (s430) a ratio (K1) between NOx contents downstream and upstream of the SCR catalyst (260), raising the temperature (s440) of the exhaust flow to vaporise reducing agent crystals with a view to cleaning, determining (s450) a ratio (Kn) between respective NOx contents determined downstream and upstream of the SCR catalyst (260) at a temperature (T2) of the SCR catalyst (260) at which reducing agent crystals vaporise, comparing (s460) the ratios (K1, Kn) and using this comparison as a basis for deciding whether reducing agent crystals have been removed to an intended extent. Also a computer program product containing program code (P) for a computer (200; 210) for implementing the method according to the invention. The invention relates also to a device and a motor vehicle equipped with the device.</p> |
