I am still having trouble correctly fixing the low speed fan issue that many here have run into. Here is what I have done so far, please let me know what I did wrong or should do next! I am currently stumped

First, I have an 03 MCS (10/02 build date) with the earlier style cooling fan.

• My car had no low speed fan and the high speed fan would cycle on and off. I replaced the fan with the correct 2 plug fan
• I thought my car was fine, I was driving with the windows down for 3-4 weeks until it got really hot outside and I decided to use the A/C. When I did this the A/C was only cold when the car was in motion (no low speed fan)
• I have checked all of the fuses, relays and all are fine

Currently I drive the car with the smaller of the two plugs going to the fan unplugged. By doing this I have the fan functioning with the A/C on and the car not in motion. As soon as I plug in the smaller plug the fan stops.

Can anyone tell me what I am missing here? Does the small plug on the car side of the wiring lead to a thermostat that is bad? Am I hurting anything driving it with the small plug undone? The car is not running hot.

thanks for any help you can provide, Brian

 

I think that plug is for the power steering fan(?) I think..

Mine did the same thing, I replaced the fan unit, all better.

11/02 build

 

Just want to make sure I have this right, you replaced the small ps fan to correct it?

I already replaced the radiator cooling fan. Guess I will check the ps fan tonight, I have not had any ps issues to date

 

I am willing to take a stab at making some sense of this. I do not claim to be an expert on the inner workings of the Engine Control Module. Here is what I have observed on my Jun O2 build "S":

The two pin connector controls a relay in the fan shroud. When energized, the relay turns on the high speed radiator cooling fan and the power steering cooling fan at the same time. If the two pin connector is not connected, the relay cannot be energized and the radiator cooling fan will always run on low speed, and the power steering cooling fan should not run.

 

^ What he said^


And I have replaced both, but was referring to to the cooling fan which on our early builds has the resistor built in. But if this was bad on yours, I don't think the cooling fan would work at all?

Not sure why you are experiencing problems, are you positive all fuses are good?

 

I have the same issue. I was sitting outside my wife's office waiting to pick her up. I had the a/c on and was reading some e-mail on my phone when I looked up and saw the coolant gauge pegged. I turned off a/c and as soon as I got moving it all returned to normal. But for a couple weeks before this I noticed cooling fan was running at strange intervals. After the overheating incident (coolant level was fine at that time) I noticed fan has not been running at all, then I notice a/c don't blow cold air unless I am moving. I checked fuses everywhere and even swapped relays. I found a 50 amp Jpeg fuse blown in the under hood compartment. I put in a new one and started the car and then smelled electrical burning scent. I put blown fuse back in so thats when I saw this post. So anyway make sure you check that fuse. What worries me is I just ordered a coolant fan thinking it was that, but now see you guys might think it could be power steering fan. So I'm curious if we both have the same thing going on. My MINI is a 05 MCS. I will not be able to check P/S fan till the weekend but I'll post what I find. Good Luck with yours!

 

Thank you for all the replies, they are greatly appreciated.

So when I got home tonight I checked all the fuses again and they appear fine.

I plugged the smaller fan plug back in and with the car on jack stands I had the car running with the A/C on and looked underneath. NO powersteering fan movement. I left it like this for several minutes, the car was warmed up with the radiator cooling fan running the entire time and the powersteering fan never came on.

I then removed the PS fan and made a pigtail and hooked it up to a battery charger.....nothing. You could feel it pulse a bit when the current was added to it, but it never spun. I reinstalled the nonfuctioning PS fan and guess I will be ordering a new PS fan now. Thanks for pointing me in the right direction.

Unfortunately I am going to have to keep driving the car back and forth to work until I get a replacement PS fan. I have yet to notice any power steering issues. Only 9 miles each way so hopefully it wont get hot enough to hurt anything.

 

From what I have researched here on NAM, the ps fan won't come on until
necessary. Does not run all the time.

Did you make sure it spins freely, not bound up?

 

I am a bit concerned that apples and oranges are being mixed

First, the APPLE... As I see it, every 1st generation MINI should have the low speed radiator fan running when the engine reaches normal operating temperature . When your car reaches normal operating temperature, the radiator fan should run, if that does not happen, there is a problem.

Next, the ORANGE... When the Engine Control Module senses that something is happening out of the ordinary, it will cause the radiator fan to go to a higher speed. When that happens, the power steering fan comes on at the same time as the radiator fan goes to high speed. This will only happen if certain conditions are sensed. I believe that there are at least three things that can cause the high speed radiator fan and power steering fan to come on. The first is a higher than normal coolant temperature, the second is a higher than normal air conditioner compresser pressure and the third is a higher than normal power steering pump temperature. If any of those abnormal conditions are sensed, maximum cooling is needed. My experience with my car has taught me that it is not always possible to tell just when the ECM might decide to turn on maximum cooling. Some cars will have their high speed fan running and others may not, even if conditions are identical for both cars. Suffice it to say that, if your high speed cooling fan and power steering fan NEVER come on, there is a problem, especially if you have been driving the car hard in the summer time with the air conditioner in use.

 

Yes, it spins freely

 

So I let my car run in the garage for about 15 minutes tonight and used the gauge cluster (#7) to measure actual coolant temps.

At idle in the garage the coolant ranged from 91-100 (195-212F)
During a spirited run in the country it ranged from 101 -106 (213-222) with the fan cycling on an off a few times.

The low speed fan on my new replacement radiator fan never worked, the power steering fan never worked as far as I can tell.

So I have read on here many times that the power steering fan comes on with the high speed fan when you turn on the A/C. is that true? I have tried this and have never been able to get the ps fan to spin.

Through all of this the temp gauge stays right below the middle where it always is.

I have ordered a replacement PS fan. Should I put a new thermostat in it as well?

 

I pulled out all of the 50 amp Jpeg fuses and they looked fine to me. Honestly it was the first time I have seen that type of fuse, so fine to me means that the two solder looking dots in the fuse are still present and connecting the metal wire together. I assume when one of these fuses are bad they melt.

 

I am not sure of that. The low speed on Artoo, 10/02 build '03MCS, does not run until temp comes up or I turn on the A/C. Low speed always runs with A/C on but not necessarily at ALL other times.

Rich

 

Per the Bentley manual, and confirmed by my ScanGauge, the fan operates at low speed at 221F, and turns off at 214F. The fan switches to high speed at 234F and remains on high until the coolant temps drops by 7F. Supposedly it also turns on when the AC is on and the AC system pressure reaches 8 bar (114psi)

 

This makes sense with what I observed with my car last night.

If you turn your car on first thing in the morning and turn the a/c on high, does the cooling fan come on within 15 seconds?
I have read on here that it should, my car does not.

I have never seen the ps fan run, never had the temp gauge over the middle range, and I have never seen over 222 degrees F.

I ordered a ps fan last night and I would like to know if I need it. I guess swapping parts out myself is still cheaper than driving over 100 miles to the closest Mini dealer for assitance I want to put a 15% pulley on my car, but I am not comfortable that there isn't still a fan issue to resolve first.

 

I'm heading into the weekend armed with a new P/S fan. A new coolant fan and a coolant temp switch and a couple of J-peg fuses. I think I'll start with the P/S fan first and go from there. I'll report in as to what I figure out.

 

Well my problem turns out to be the coolant fan assembly which I'm having installed next Monday. I installed the new P/S fan anyway.