2000 Mercedes a/c
If you haven't figure it out yet, let me know what it is you are trying to do.
There's an unassuming button known as "EC" or economy climate which is probably what's tripping you up. If you want a/c to blow cold you'll need to deactivate the "EC" mode and activate the "AUTO" Climate mode. Now you can adjust the temp with the UP/Down arrows.
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