After 18 months of ownership from new I have just noticed only the drivers door mirror dims. The glass in both wing mirrors is different. The drivers door glass has a noticeable 3mm wide ring around it with the inner portion looking slightly darker than the outer. The passenger mirror is not so.

 

The manual is vague because it refers to both exterior mirrors as 'mirror' and not the plural, mirrors.

Edited 4 November, 201510 yr by DonjSZ5

I thought only the drivers side wing mirror is the one that dims so yours is ok or we both have a problem.

Mine only his dimming on the driver's side (and the internal one).

Passenger side is standard glass but can be retro-fitted with dimming if required (ask Eddie-NL, I think he's done it).