2009 W209 CLK 350 Conv Radiator Fan constant running

[abmunro]

Hello

I have read a few threads about this and one thread suggested that I needed a new Engine fan with built in control module.

I have replaced the fan and this has not fixed the problem.

I have read that I might need new ECU, poss problem with AC etc

I removed fuse 51 - Engine fan fuse and fan continued running.

Is there a logic process of part changes to repair this fault?

Cheers

Tony

 

[topdown]

It could be the air con pressure sensor. It is located on the condenser and costs about £40. It will need the aircon degassed to change. Best thing is to have on a star machine to confirm. Cheaper that changing out parts.

 

[Salal]

Yeah get diagnostic done and see if there are any faults which there should be and that may point you in the right direction. Otherwise you’ll just be changing parts until you’ll get lucky eventually.

 

[mersum1es]

either faulty AC/temp sensor or lack of voltage (blown fuse?) somewhere and because of missing data fan control is turned full for safety

 

[abmunro]

OK Cheers Guys

 

[anderoo]

Mine runs constantly too, just because I always leave the climate control on auto. If I turn it off, the fan stops running (after restarting the engine).