Could someone please enlighten me as to the purpose of the black "button" in the picture that is compressed when the door is shut?

Alex

A switch to turn the interior light on when you open the door perhaps.
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Bubins said:

Could someone please enlighten me as to the purpose of the black "button" in the picture that is compressed when the door is shut?

Alex

Click to expand...

Hi Alex, it is for the interior light that is fitted into the lower edge of the rearview mirror. Depending on the position of the switch on the mirror will see the light come on or not. The bulb is a fiddle to change and you may find replacing it a little difficult to source.
Ian.