Particle filter in a mirror why one earth is there a filter in the mirror ?


There isn't, but there is an ambient air temperature sensor used by the engine management system. Pattern mirrors are cheaper but don't have this sensor and it causes engine management errors leading to clogged DPFs.

There are several iterations of Sevel van mirrors at varying prices - Jerry seems to be unlucky that his is amongst the most expensive. At a guess it is electrically adjustable, heated, has a radio ariel in-built as well as the temperature sensor.

Sevel parts are pricey - my Ducato MH was damaged by another driver's actions, resulting in a damaged front wheel as well as the mirror housing. Less costly mirror than Jerry's, but still over £1k + Vat for a bare alloy wheel & the mirror. There is a reason why you will see many MHs having white or yellow "mirror protectors" stuck over the outer mirror shell !

Nigel B.