adotomov

Hey guys, I've been getting this message on and off for the past nine months. According to the computer, it indicates that the radiator fan doesn't turn on at certain temperatures. The strange thing is that most of the times it is at temperatures around 60-70 degrees.
What bothers me is that it is doing it only when I am driving with AC on.
Is this some sort of a computer bug or is it a symptom of a serious problem.
The car never overheated, the radiator fan starts spinning at temperatures around 90 degrees even when the AC is off and even during the summer when temps go up to 100 the temperature gauge never exceeds 90 degrees.

cij911

There are two modes (IIRC) for the fan and it sounds like, for what ever reason, your fan is not kicking into the high speed mode. Generally you want more airflow over the AC radiator when the AC is on.

You will likely need access to STAR to get more detailed code information, but I would guess it is something silly like a relay. Sorry I am not more help.

Plutoe

There is another school of thought------the fan is programmed to come on when the engine coolant exceeds a temp. The second case is when the refrigerant temp exceeds a certain point.

If like you say the fan comes on when the AC is on---------I would have my AC system checked, because the refrigerant temp is getting way to high. Good Luck!!

adotomov

Thanks guys, for the replies. I should probably correct myself and explain that by AC I mean both cooling and heating. I use the Auto function and right now the temps are between 14 and 30 so it is pretty chilly.
I went to my repair guy today to check the error codes and the message had come up two times in the past two weeks. The first time was when the temp was 150 and the next time at 160. According to him the fan should kick in at 185 at first speed and at 205 the second. I mean, come on, 150 the engine is still "cold". Optimal working temperature should be between 185 and 195. It really doesn't make sense to me this error.

Plutoe

If it were me, I would replace the coolant temp sensor!

spratt22

HI IVE HAD SAME PROBLEM FOR 18 MONTHS NOW CAR RUNS AT 60-70 DEGREES, FIRST TIME IT APPEARED MERCEDES SAID I NEEDED A NEW RADIATOR FAN AT A COST OF £879.ANYWAY I JUST IGNORE MESSAGE AND KEEP AN EYE ON TEMP GUAGE.ALSO I NEVER USE AC.I HAVE SWITCH IT ON TO TRY IT AND FAN KICKED AS IT SHOULD SO I CANT SEE HOW I NEED A NEW FAN.ANYWAY AC WHO NEEDS IT IN THE GB JUST OPEN A WINDOW.BY THE WAY MY CAR IS A 2003 W211 320CDI AS LONG AS CAR IS NOT OVER HEATING IGNORE IT WAS ADVICE FROM INDI

AMGAffalterbach

Thanks for the response, welcome to the forum, but PLEASE stop with all caps for the love of God.

adotomov

Ignoring a message is usually against my policy, but I've been doing it anyway for over a year now. I got the same advice from my Indi, to ignore the message, observe the temperature and I should be fine.
Plutoe, do you know where is this coolant temp sensor and is it an easy change or I should go to my repair guy.
Thanks again for the help!

Plutoe

Without a VIN my guess is that you have a E220/646.821 engine. If that is the case the temp sensor is on the thermostat housing!! Cheap part, however without looking at the car or WIS I can't estimate from here the degree of difficulty.

Best, take a look yourself then locate the sensor------what do you have to remove, if any???????

ozusa

The fan spins when it's told to, at the speed it's told to. But it takes a controller to tell it. The controller is on the fan surround/shroud and a sub-component of the fan part number. I don't think you can buy them separately. So, when your dealer wanted to replace the fan, they probably meant you need to replace the whole thing in order to get a new fan controller. I presume the controller takes coolant temp as one information input and A/C pressure as another.

BenzKiddAMG

I added coolant my E55 because the coolant light came on in the gauge, now the car keeps over heating...what should I do?

cij911

Option A: You could take it to the nearest desert, race it for at least 5 days straight or until the motor blows up, and then come back and tell us what your dash tells you....

Option B : You could have the car towed (on a flat bed) to your trusted mechanic and have him/her diagnose your problem.

Personally, I would opt for Option B....

Plutoe

When the coolant lamp came on---where do you suspect the gauge was at?

When the engine is cold------what level shows in the overflow/expansion tank---if it is up to the correct mark, then the issue is that either coolant is not recirculating because the thermostat is stuck or the thermostat is open but the pump is not circulating the coolant.

This all pesupposes that coolant is not leaking from the engine

vettdvr

If the fans are running, radiator clear unobstructed, change the thermostat.

ozusa

It's probably the thermostate as VettDVr says.

But also....

Are you losing water from the system? (I read that you had to top it up at least once) If so and you don't see any obvious leaks, remove your engine oil filler cap and see if there is a milky emulsion inside the cap, or whitish smoke from one side of the exhaust when the engine is running. If either of those, you could have a leaking head-gasket. But most likely it's just the thermostat.

BenzKiddAMG

Thanks guys I already fixed the problem...what happened was I got air into the hoses so the coolant wasn't circulating and I drive it that night and it was over heating really bad...so I woke up early in the morning when it cooled down and took off the cap and started the car up. While the car was running I had the AC on blast and started filling it with water till it stayed full....put the cap back on and it's been running like a champ...

03 E55 AMG 5.5L v8 Kompressor

spratt22

HI GUYS JUST AN UPDATE STILL KEEPING EYE ON TEMP AND CAR STILL RUNNING FINE. IT DID START RUNNING A BIT COOL 60 DIGREES SO REPLACED TEMP SENSOR ON THERMORSTAT 10 MINUTE JOB JUST REMOVE ENGINE COVERES SENSOR JUST NEXT TO OIL FILTER UNPLUG ELECTRIC PLUG PULL SENSORS RETAINR PIN BE CAREFULL NOT TO DROP IT I TIED BIT OF WIRE TO IT BEFORE REMOVING IT.SIMPLE JOB YOU DONT EVEN HAVE TO EMPTY COOLANT JUST TOP UP LITTLE YOU LOSS ABOUT A CUP FULL.CAR NOW RUNNING BACK TO NORM TEMP.I GOT ANOTHER GUY I KNOW WHO HAS FULL MERC DIAGNOSTICS AND HE CANT FIND ANY ERRORS IN SYSTEM HE SAYS MAY BE A DIRTY CONECTION THAT ONLY SENDS MESSAGE ON NOW AND AGAIN GOING TO CLEAN THEM 2MORO WILL KEEP YOU POSTED

yenoors

I'm getting the same message, but the coolant is running normal temperature and there are no leaks. I had this trouble this winter, and the fan was running full blast in below 30F temperatures....replace the expensive fan and the computer. wow...$$$$. Now the fan is on full blast again and now the message is Coolant - visit workshop. Also, earlier this summer, when the a/c turns on maximum cool, the engine fan would go to max until the a/c stepped down a notch.

AMGAffalterbach

Please turn off caps

phalen302

I had an issue with coolant temp sensor and it kept throwing messages. Since replacement; no issues at all.

spratt22

Hi all sorry no been in touch sooner about message coolant visit workshop,at inde garage the guy plug his laptop in came up no error codes in coolant system so he sugested cleaning where electrics plug in down right hand side of radiator 5 minutes and a good spray of wd40 haypresto never seen message since.the problem is common as muck,spoke to merc tec he told me its a dry connector which they are famous for but dealer will tell you its your fan.by the way i spray the plug every now and again.cap lock of captian lol

verlin samonte

i also have this error coolant visit workshop . using MBII odb , code i got is p201f-002.

1. It is intermittent, if you start the car and got the error, error will not go away unless you restart the car. when you restart the car it can be either you have error or no error. if you dont get the error , fan will work.

2. as of the moment , i can replicate the error. condition is car engine is cold, normal temperature in our country is around 30 degree C and up.
a) connect the scanner,
b.) insert key and put to position #2 , dont start
c) check scanner(error will be detected BUT i dont see it in instrument cluster unless i start the car)
d if scanner detects "coolant vist workshop" , p201f-002 , remove the key , go back to b) . if you dont get the error at this point you can start the car without problem, fan will work fine.

im still trying to figure out what is the problem .... anyone have the same experience?

ot1

are you mixing Fahrenheit temps with celsius? Please use C or F after your numbers, I suppose Bulgaria uses Celsius but seems like your temps are Fahrenheit, chilly would be above freezing but 14-30F is below freezing.