pe6oo wrote:Do you have some idea how i can change it or how i can take it out
I have never had to change one, sorry, I don't know how its done, but if its like the other button and switches found on the C3 they are usually clipped into place.
It can be difficult to see the clips without removing the part which makes it more difficult.
My suggestion is to try to remove the plastic panel that the switch is mounted on, then you may be able to look and see how the switch is mounted. Then you may be able to work out how the switch is easily removed.
If you take photos on the journey, then you can add them when you find the solution.
I did look to see if I could find an image of the switch removed but the photos I see only show the control knob face on.
pe6oo wrote:And also if it's from the button why I can not open the rear whindow?
I don't know. You suggested the switch. I do know that some switches are locked out of operation if certain conditions are not met (like the roof position). So I could only guess if the roof switch is faulty that the computer has disabled the rear window switch to avoid a possible problem of things being able to be opened when they shouldn't be.