W203 143
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W203
W203 143
My cabin blower fan stops working in AC mode after about 15 minutes of operation. I've already replaced the blower motor and regulator for the problem of 'Auto' mode intermittently shutting down (light on button goes out) one side or the other or both sides. When the fan stops the Auto mode lights stay lit and the fan speed indicator shows fan active.....but nothing is coming out of the vents. If I cycle the car off/on then the fan starts up again for another 15 minutes. Anyone have a schematic of the fan circuit? Any guesses? Thanks, Mark
MBWorld Fanatic!
Joined: Dec 2003
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From: BC, Canada
2003 C230K Coupe Orion Blue
Maybe try a resync of the HVAC stepper motors. Hold the defrost and recirculation buttons (first 1 buttons in the row) until they start flashing yellow/orange. Give it at least a couple of minutes to cycle every motor (you'll feel the air moving to the dashboard/floor, as well as temperature going hot/cold etc.), then shut car off and wait 2 minutes (I'd wait 5 to be sure). See if that fixed your problem.
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W203
I tried this option. I have a problem with one of the modules (the one that blows on the legs on the left side), but it has been working like that for 3 years now. And the new problem appeared 2 weeks ago.
