I bought my car 6 months ago, and since i bought it ive had the fan always come on after i stop my car. Recently, every time ive been stopped at a light or in a drive through, my water temperature would go way up, up and over 220 degrees. I have a scanguageII and I realized that everytime my car was idle, the temps would increase and as id start to drive they would go back down. Well, i checked the coolant tank, and it was empty. It appears that the recent owner put only water in the tank, and due to it constantly boiling and sitting, it created a lot of rust in the system. this also caused the thermostat to stick shut. Over the last day i had the whole coolant system flushed about 4 times to get all the rust and stuff out, purchased a new thermostat (which now comes with a 2 year warranty from the dealer, no matter who installs it), and now everything runs great.

Before my average driving temperature was around 204, and now my car runs anywhere between 188-195. Doing so also caused the low speed fan to start comming on.

Anyone experiencing overheating at idle problems, id recommend checking the thermostat. If anyone has any questions, feel free to ask. I learned plenty about the cooling system on these cars just over the last few days.

 

Thanks for the write up and info - You got yourself an awesome looking DS But. the Thermostat is totally mechanical and only regulates the flow of coolant when a certain temperature is reached in the system. And in your case, temps were well within the range for it to be flowing.

When the high speed fan kicks on at drive up widow of a fast food restaurant or stop light, and you are NOT running your A/C at the time, it means your coolant temps have reached critical mass, and were not being cooled by the low speed fan. This is usually an idication of a failed part of the fan assembly.

In our case - at about 205 degrees the Thermostats open and allows the flow of coolant thru. But before that time, the low speed fan should be doing it's job too.

And the fact that your low speed fan is now working unfortunately can have nothing to do with a thermostat replacement. So still keep an eye on the temps as the fan's assembly's .3 ohm 13 Volt low stage resistor is apparently failing and will burn out soon.

I have done weeks of research on this issue, and even have a vendor for the resistor alone, but unless you purchase them in bulk, a single unit costs as much as a whole new fan assembly....and since it is hard wired in there, also a bit of a PITA to replace, so it made no sense to just replace that single part. Dealer cost for the assembly is just under 400 dollars. The eBay one is same as OEM and is manufactured by TYC Inc. for about 80 dollars.









This is what a good one looks like

 

thanks for the info gray raven. yes the low speed fan kicked in before, but i think i just noticed it now more. but due to the fact that the thermostat wasnt allowing coolant to circulate and the fact that there was no coolant, it is what caused the problem. before the cars water temp would increase slowly at idle, now it remains constant and when the low speed fan kicks in, it drops. before the fan would kick in but the temps would still increase, then the high speed fan would kick in and the temps would still increase... everything runs A O.K now though. Id say as long as your fans are comming on, then the problem is definitely the thermostat. and the only reason i did this writeup was because i too searched for weeks for the problem and a solution, so i kinda just wanted to sum it up here.

I would like to check if my car has the new wiring harness for the radiator system and fan is it? i know there was that recall thing to get the new wiring harness... anyone have any idea on how to check for this?

And thanks for the compliment, i love your car as well, wanna wrap my interior in the CF vinyl?

 

np, Keep an eye on that LS fan. It's not the best design I have ever seen and seems to be as much of an issue as is the power steering pump fan and it's electic pump.

As far as recall stuff goes, it's a good time to just stop in to any MINI dealer, introduce yourself to the SA, and have him or her pop your key into the service POD, from that they should be able to run your car thru their national data base and determine who owned the MINI before you and what service / recall work was performed if any. And it may give you the opportunity to get to know the rest of the folks down there.

The Dry Carbon Fiber look seems to be really catching on. Sure glad to do any parts you need to have done. Send me a PM we can work out the details after the holidays...

Merry Christmas!

 

Gray Raven: I too have a failed low speed resistor. I have followed this issue and had purchased a 100W 0.33 ohm wire wound resistor from Mouser Electronics; cost me $15 or so as I recall. I have not yet removed my fan assembly and explored this repair, but the resistor I bought looks nothing like what you picture. I anticipate a 'remote' location for the new resistor, but am I heading in the wrong direction here? TIA.

 

To check to see if you car has the service bulitin performed....simply look in the area of the fan plug. If there is only one...and it is a newer car, it has been done. When the dealer does it, they cut and tape off the plug that was formerly used to provide power to the ps fan.
Also the fuse panel cover by your foot in the car is swapped out to keep it correct, as there is a fuse added there.

 

And just to add to the info....I may have heard the high speed fan come one once or twice in 4 years without the ac on....my temp guage is pretty stable...moving and stopped for longer periods.....if you can see the guage move when you sto for a minutes or two...you might have something else going on....I too have replaced my fan...same problem...have the tyc from rock auto....very happy with it.

 

well the guage wont move after a minute or 2, it wouldve shoot up up after being idle for a number of minutes. i know the temps are going up though because of the scanguage i have. thanks for all the info guys, ill definitely have to have the dealer check it out. im not to electrical savvy when it comes to this stuff lol.

 

Is there a DIY on how to replace the fan assembly or is it self-explanatory once I get under the car? Thanks.

 

Swapping out the fan on an S is a PITA.
remove the bumper cover, bumper, unmount the AC condenser (leave it connected)....etc. It is not really that hard, but a real pain.
Someone does have direction on how to do it...and pictures on flicker or something I believe. But if you have done engine work on a MINI, it will be pretty self explanatory.

 

yea ive heard it a PITA also, but like ZippyNH said, if youve done engine work before then itll be alright!! are you experiencing overheating problems as well dragonwang?

 

Yes, this overheating problem still occurs after I changed out the thermostat/gasket and bleeded the coolant system myself. The thermostat was leaking at the time, so I was sure that the overheating issue was relevant to the thermostat. However, it still happens when I stop at a drive-thru fast food restaurant or a stop light for more than one minute I would say. When my car starts moving, the needle gauge goes back to the middle.

When the needle gauge goes past the middle, I hear the loud fan. After a short while, the needle would go back to the middle.

 

o wow. then its gotta be the fan... maybe one of the gurus on here can help cuz thats definitely outta my league haha.

 

how much did it cost?
Dropped my S off yesterday for the same exact problem. (to the T) I was shutting off my engine at stop lights.

 

The fan from the dealer is 350$ plus install......you can get them for less than 100$....actually 85$ from 3rd party vendors like rock-auto. Install would be maybe 2 or 3 hrs....quicker if you have done a lot, but I assume they bill the listed amount in the MINI/BMW repair book.....
if it was just the thermostat.....I'm not too sure.....but the fan seems to be a very common failure...there are 3 or 4 epic threads on the failure of the low speed resisitor that allows the fan to run on slow speed.

 

if your talking just about replacing the thermostat...
bout $120 from the dealership for parts (housing and thermostat and gasket)
then i think i paid maybe $50 bucks labor from my trusty mechanic. isnt a hard install at all. im not sure about exact labor cost cuz like stated above i had other stuff done as well. as far as replacing the fan, ZippyNH gotchu on that one.

 

i believe the op said :it was stuck shut due to rust , therebye not allowing coolant to flow." i experienced this same issue with a ford 4.9l and it was the same exact thing .

 

Is there any way to confirm that the fan is shut or malfunctioning? Is the fan viewable just by popping the hood? Thanks.

 

You can see the fan...but you cannot do anything to determine if it is working correctly without dooeing more legwork.
To see the low speed resistor you must un-mount it....by then you might as well mount the 85.00 aftermarket one from a company like TYC...(order from rock-auto.com, e-bay, etc).or the 300+ one from the dealer....both seem to be comparable. If changing it is beyond your ability, it is something that a dealer would most likely catch on an inspection I or II IMO.
The best way to see if the fan is operating correctly is to observe how it works. If you just have the fan turn on when your car is very hot, almost overheating, and the only time you ever hear the fan, it sounds VERY loud.....never two different pitches....the low speed is likely out.
If you let you car idle from cold, A/C off, after a few minutes the fan should turn on low....mostly continuously. If it turns on and off every few minutes or so....not a good sign (especially if it is really loud...and the temp gauge is near the top...). If you have access to an OBD2 scanner (like the scan-gauge II), you can check the temperatures it it supposed to turn on....the low vs the High...there a several threads on how to determine if the low speed fan is shot in much more detail......the above description is just a quick way to check from my memory.
most people first notice the problem when their car is almost overhaeting at traffic lights, etc.
You should first check to see if the fan runs at all. Early...pre 05', (and a few early 05's, like mine,) were delivered with the power steering fan, and radiator fan on the same fuse....if the PS fan seized, and blew the fuse, the radiator fan would no longer run. The dealers modified many of these cars for free under warrenty.... On modified cars, the two were split, and a new harness installed, relocated the PS fan to the drivers side fuse panel.
Next I would check you fluid levels....many GEN1 MINI's have the radiator tank leak...it was actually recalled, and a slightly better tank installed....that still leaks along the seam at some point...usually very slowly as some steam or a drip... This tank takes maybe 10 minutes to swap out, and is pretty cheap. Because of this leaking tank many cars get very low on radiator fluid without the owners knowing. Be sure to top off with only BMW/MINI fluid.....(BLUE), or the equivalent, (Zyerex g-05 is the same I think). DO NOT USE LONG LIFE, UNIVERSAL, YELLOW or GREEN unless your car has been properly switched over as parts of it regular maintenance.
Good luck, and remember the most powerful feature on this site is the search button. Hopeful this info was helpful to you!!

 

Now that you've mentioned it, my car is a 2005 model, but my production is September 2004. Does that mean the power steering and radiator is on one fuse? Which fuse would I check to see if it's blown or not? I don't recall the dealer ever changing to a new harness for the times that I have gone to the dealer for warranty work.

 

Yes. Mine was built after yours, and had to be modified. It was done for free after I had the car for 6 months or so.....my PS fan was seized on a service appointment, and the dealer did it proactively to bring my car up to the same build as the 05's that were being delivered to prevent future issues. (it was not truely a recal, but a do if needed or if a custmer complains I think).
When the harness was modified, a fuse was added on the drivers side fuse panel. That might be the best place too look.
If the fan NEVER runs look first to see if the fan fuse, I think under the hood is blown. I would also check the PS fan....it get full of grit...and tends to get jammed. You can get a replacement at WayMotorWorks for like 130$, and install in pretty quick....cheapest I have seen it, cause it is the fan only...remount it on the old fan holder/grill....takes like 5 more minutes, but save some pretty serious $$$. Next I installed the OEM fan duct kit from MOSS.....it is very different from all the aftermarket solutions, and much more effective....it was installed on the cabrios and I think the 06 autos........a great $80 solution to extend the life of the PS fan and PUMP....simple, OEM, etc. Upgrades the car to the way it should have been delivered IMO....and prevent the PS fan from getting chewed up, and siezing, thus blowing the fuse.

 

yup, definitely listen to your fans and see if you hear 2 stages of the fan. one will be a little quieter obviously lol. Just for an update, my car has now had no cooling issues at all, and i never hear the fan come on after i shut my car off anymore, and that dummy guage never shoots up anymore! Guess all my problem was, was no coolant, and a bad cap on the tank preventing pressure.
Definitely check fluids before going through the work of checking resistors and and all that stuff. start from the basics.

 

Thanks for the GREAT tutorial!!!
Just did my back brakes in under an hour and a half!

My 2 cents:
You only have to take apart half of the caliper to change the rotors.
Once you have the half off (the half you have to take off anyways to change the pads) the rotor will just slip out.

Thanks!!!!
Ty