748Ducati

Hi I am having a problem with my heater blower, it still has hot air but it doesnt blow hardly at all. I tried checking for a blown fuse... Didn't find any. Anybody have a clue what to try next? Thanks George

NZ_Benz

Blower motor regulator it sits on top of the blower motor under the pollen filter, it's about $300 or so dollars to replace.

Gman91932

When this happed to me it was the Duo Valve. Also the vacuum pump under the back seat was disconnected and it was also related to blower failure

G

NZ_Benz

That can't be possible, my PSE pump is sitting next to me on my desk for repair and my blower is working, the regulator is a well documented issue, also duo valve is related to tempreture issues not the flow of air.

syljua

Diagnose of the regulator;
http://www.mercedesshop.com/Wikka/W140BlowerMotor

By doing that, you will also discover if your main
passenger air filter is due to replacement (clogged one makes
the motor work hard, to suck air in)

br,
syljua

syljua

Electrically wise, I agree, but remember that the PSE
also functions as giving vacuum to the flap plenum
when engine is not in use.

My guess - perhaps there is no valve
in the plenum when the PSE is disconnected, and flaps
will not get moved by the engine vacuum?

br,
syljua

NZ_Benz

True but in the same way when you use the defrost of something and the air is not being thrown at you, you can still hear the blower spin up. So a lack of airflow due to the flaps being closed is a different problem than a dead blower regulator.

Rod Spohn

It does sound like the regulator. This is an easy fix for even a semi good DIY kind of guy. The cost of the part is not to bad, so if you do it yourself its maybe $150. Buy a new filter while your at it, it has to come out anyway so its a good time to change it. Try www.autohausaz.com