The engine fan uses a electro-magnet to lock up at 100C..fuse, relay, & switch.

The center vents will never put out heat..if you are getting heat from the outer vents & OR footwells then you have a vacuum loss in the system.

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MERCEDES Benz Master Guild Technician (6 TIMES)
ASE Master Technician
Mercedes Benz Star Technician (2 times)
44 years foreign automotive repair
27 Years M.B. Shop foreman (dealer)
MB technical information Specialist (15 years)
190E 2.3 16V ITS SCCA race car (sold)
1986 190E 2.3 16V 2.5 (sold)
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