Will the blower come on when one of the manual fan buttons is pressed. If it does:

Cut a 1 centimeter square piece of paper and hold it to the small grille next to the rear view mirror while the key is on. If the paper does not stay in place, find and fix the sample fan. This fan draws sample interior air past a sensor.

If the fan does NOT come on, check the strip fuse under the hood near the master cylinder.

Hope this helps,
Larry

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2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

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