Volkswagen Touran Owners Manual: Insulating glass windscreen

Fig. 79 Metal-coated windscreen for infrared reflection with communication window (blue area)

Insulating glass windscreens have a coating which reflects infrared radiation. There is a non-coated area above the interior mirror (communication window)   which ensures that electronic accessories, for example remote controls, can function properly.

The uncoated area may not be covered either from the outside or the inside nor may any stickers be applied to this area as the electronic components may otherwise malfunction.