Hi
I have a 1975 w115 MB 240D that has a defrost issue.

The defrost doesn't work. The problem is that it sometimes turns on, but it is unlikely that it works.

I've heard that the defrost is activated with a vacuum. Is there anyway I can bypass the vacuum to test the unit? Where are the connections for the vacuum and the connections for the power located?

Thanks for any help.

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1975 W115 240D

Since the vents are controlled by mechanical levers, you must have the classic W114/W115 fan failure.

Good luck, rumor has it that the fan in a W114/W115 was hung on a wire and the rest of the car was built around it.

Some people have had success going in through the plenum via the grill in front of the windsheld and lubing the fan bearings.

Otherwise, disassembly of the dashboard is required.


Jim

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14 E250 BlueTEC black. 45k miles
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