I have no unit to trade it in.
I am getting only hot air out the defrost vents - get full heat, windshield only.
It slowed down after I removed a fan fuse but hot air still comes on high speed.
May I close air flow lines by directly appling the battery +12V to pins (I need to check numbers) on the connector to Climate Control Unit?
I will check a diagram again and post numbers.

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1987 MB260E 187K