The rear quarter windows are electric and can be opened and closed by two switches located below the climate control. The switches are marked with a picture of a window with a 3 in it. One for the left window and one for the right.
see page 20 and 106 in the owners manual. https://www.mbusa.com/vcm/MB/DigitalAssets/pdfmb/ownersmanual/2000_m320_m430_55amg.pdf
Don't push it closed as that might break things.

__________________
Dave
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2000 C230K Totaled @104K
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