Just started this morning, front fans keep turning on and staying on till I turn off the car. its winter here and my car is not over heating. the tempature on the gauge stays at 80 degrees. i check the fuses and they are okay.

I call MB parts and they said might be a relay which is located in the fuse box. I pulled out the fuse box and the other plastic part which exposes more fuses and pulled those big fuses one by one and fans stayed on even after pulling all of them.

What can the problem be that the fans come on in the dead of winter?

 

Anyaone? This problem is really annoying as the fans are pretty loud. I will be pulling the fuse out to stop them from running but I want to fix this asap. thanks.

 

low coolant level..
do you have onboard diagnostics like the w210 models?
http://www.eclassbenz.com/node/27
worth a try if you do run the values and the errors and see if any for the fan relay or coolant temp sensor come up.
have you tried a hard reset of the system?to see if that clears the problem.
ohlord
the relay has cooling fins and if it gets hot the contacts will stick,sometimes a tap with a wooden screw driver handle will free it up.sort of like freeing up a stuck duovalve
call the dealer and ask for the part number so you make sure to bonk the correct relay.

 

low coolant level..
-- The level on the resevoir is on the FULL mark so Im sure that's okay.

do you have onboard diagnostics like the w210 models?
-- I have no idea, i will have to look into it and try the steps for E series on the site you linked to see if it might work.

have you tried a hard reset of the system?
-- You mean disconnect the battery? No, but I will do it thursday morning.

the relay has cooling fins and if it gets hot the contacts will stick,sometimes a tap with a wooden screw driver handle will free it up.sort of like freeing up a stuck duovalve
call the dealer and ask for the part number so you make sure to bonk the correct relay.

--Sounds good I will call and get that part number.

Thanks OL!

Any other thoughts people?

 

hey OhLord, i took the cable off the battery for about 2 hours so as to reset the ecu. it did not work, the fans still come on. Any other ideas? Oh, and I doubled check the fluid level and its all good. i still have to call mb to get the part number of the relay so i can hit it as you mentioned.

 

i think mine is doing the same thing actually...

so i'm of no help

 

If you get it fixed before me please post what it was.

thanks!

 

mine is in storage- noticed it while working on the sc install etc., but in no real rush to fix

you'll likely have to let me know