Vito W447 coolant fan running continuously

[DaveG1709]

Hi everyone
has anyone encountered this I’ve looked through the threads and can’t find any info.

My Vito van 1.6 diesel suddenly has the fan running continuously upon start up until engine switched off. The temperature gauge is running slightly higher just above 80 degrees.
no warning lights are up.

the coolant level is correct, no leaks,

 

[Mattylamps]

Any luck Dave? Mine is doing the same.

 

[DaveG1709]

Update (cooling fan continuously running)
Took mine to the local garage they changed the temperature sensor and the fan module

Made no difference!

So booked it in to a Mercedes main dealer.
Their diagnosis was contaminated air intake system. Intercooler , pipes and turbo clutch. Estimated cost £2200

So I bought a new intercooler, left and right hoses, and a new air filter (washable) and pressure sensor. Cleaned the turbo without removing and all good.

 

[darrenam]

Hi how much was all that to do please. I have same problem

 

[DaveG1709]

Hi how much was all that to do please. I have same problem

I may have made a mistake replying in the wrong section so
Approx cost £700 but I had it done in stages and fab module and the tempersture
sensor made no difference
I bought intercooler on eBay and the original Mercedes intercooler hoses (2)
a new pressure sensor air intake sensor and a new washable KN air filter . My friendly garage did the intercooler fitting I did the rest. Runs great now. Also cleaned turbo with the spray cleaner .
Apparently my intercooler and pipes were badly clogged up and contaminated the hoses with oil residue and turbo needed a good clean
Last thing I will say is the temperature sensor runs at 90 instead of the original 80 mark. So if I have any further problems ECU may need looking at . But all good

 

[Bennys]

Update (cooling fan continuously running)
Took mine to the local garage they changed the temperature sensor and the fan module

Made no difference!

So booked it in to a Mercedes main dealer.
Their diagnosis was contaminated air intake system. Intercooler , pipes and turbo clutch. Estimated cost £2200

So I bought a new intercooler, left and right hoses, and a new air filter (washable) and pressure sensor. Cleaned the turbo without removing and all good.

Hi guy's need some help here , i have a vito 447 2017 cooling fan coming on full speed just when you put ignition on , you don't even have to have engine running ?
i have read some link's to this site ,
i will start from beginning , connected code reader upto van came up with U000800 the electric fan has a malfunction. the message is missing
no air con fitted & temp normal these are some of the thing's i have done No1 purchased new temp switch & short wiring loom , but i put the sensor & wire together then just plugged em into the loom of vehicle , still when ignition only switched on cooling fan comes on full , just to be sure i earth the sensor upto the body with jump cable to ensure the sensor didnt have to be earthed , still same , so left the old sensor & old wiring on , from here borrowed both fuse boxes from another van with all same spec plugged em in ,ignition on cooling fan still came on ,so put them back as they was , then i borrowed the fan motor off other van and plugged it into my van ,ign on still came on

I have read that you change the intercooler / hoses / pressure sensor air intake sensor ? ( question ) as i am looking at the oxygen sensor on the top left there is a small sensor just to the left hand side of it ,is this the sensor you are on about
any help on this subject would be great as its now doing my head in .please

 

[DaveG1709]

Hi guy's need some help here , i have a vito 447 2017 cooling fan coming on full speed just when you put ignition on , you don't even have to have engine running ?
i have read some link's to this site ,
i will start from beginning , connected code reader upto van came up with U000800 the electric fan has a malfunction. the message is missing
no air con fitted & temp normal these are some of the thing's i have done No1 purchased new temp switch & short wiring loom , but i put the sensor & wire together then just plugged em into the loom of vehicle , still when ignition only switched on cooling fan comes on full , just to be sure i earth the sensor upto the body with jump cable to ensure the sensor didnt have to be earthed , still same , so left the old sensor & old wiring on , from here borrowed both fuse boxes from another van with all same spec plugged em in ,ignition on cooling fan still came on ,so put them back as they was , then i borrowed the fan motor off other van and plugged it into my van ,ign on still came on

I have read that you change the intercooler / hoses / pressure sensor air intake sensor ? ( question ) as i am looking at the oxygen sensor on the top left there is a small sensor just to the left hand side of it ,is this the sensor you are on about
any help on this subject would be great as its now doing my head in .please

Yes that sensor can also be removed and cleaned. Check your hoses if they are clogged up best to change Intercooler