I think I got what I wanted for now. I took out the fan, cut the 2 red wires that go into the resistor, bridged them together thus removing the resistor all togehter, now when I turn on the A/C the high fan turns on but only in 5 second bursts,

What controls the fan and makes it turn on in burst and not just constantly run?

 

According to the Bentley manual, Minis with build date from March '03 and forward have separate relays for the rad fan (stage 1) and PS pump fan. They also have separate fuses. The fans go on & off together because their relays are fed by the same signal from the ECM.

 

So, I need to test my relays first because the low speed cooling fan whether the resistor is good or not has nothing to do with the power steering cooling fan working, is that correct? I just tested my pwr steering fan and it works when jumped so......... god my mind is starting to melt........... Anyone, Bueller, Frye.......... Anyone.......

 

Yes, however, that cutoff date is not written in stone. I have a 2/2003
build MC and according to my VIN and realoem and the dealer, mine should take the
before March 2003 fan, yet my car had the later part and wiring (I know this for sure
as I had to ship back the first fan I ordered and then get the from 3/2003 on one).
If you're within a month or so of March 2003 build, I'd check visually first
(older part - big 3 wire harness and small 2 wire harness ; newer part -
big 3 wire harness only).

 

http://www.bmw-planet.com/diagrams/release/en/index.htm

Good website for mini wiring diagrams

 

Well, I reinstalled the resistor, with real soldering connections this time, and made good voltage readings. Sure enough, it's ~9 volts after the resistor going down to the fan, and the fan is blowing strongly, and in bursts. I tried just bridging without the resistor to see what high fan might look like, and it blew out the 30 amp fuse for stage 1 within about 5 seconds. So I'm confident that my fan is getting the right voltage and current, and it's just a strong blower. At this point I'm declaring success and not worrying about it any more, at least until the fan decides to crap out.

 

Can someone please help me with this resitor business.

I bought that acrol resistor everyone uses for this fix. I have the pre 03 fan, with the relay on the fan. I tried simply cutting out the old resistor and runing the 2 end of the thinner red wire to the resistor. When I took a voltage reading, it was still 13v past the resistor. I tried testing the resisotr and it seems to be working, im getting .33 ohms on it. What am I doing wrong? also when the resistor was wired up I wasnt getting low speed stilnow i had a 12 battery hooked up the + to one side of the resistor, then checked the voltage past the resistor and im still geting 12V

 

Wire the resistor across a high current 12v supply, it should get too hot to touch within seconds, but don't leave it connected too long else it may burn out.

Also check you are measuring all voltages relative to battery -ive on the cars body.

Hope this helps.

Cheers

Chris

 

I understand what you want me to do. I dont think I have anything that will draw a high current. I think I might try running powert directly to the fan, bypasing all the wiring and seeing if the resistor works that way. Im just afraid im inserting it wrong into the system.

 

Ok I am totally stumped, I hope someone can help me figure this out. This is what happened.

I tested the resistor by unplugging the large plug for the fan and runing power and ground directly to the plug. ground to the brown wire and power to the thinner red wire. Mean while the resistor was wired inplace of the old one. put the power to the battery, fan runs at low speed, checked voltage past the resistor got 8.2v, keep in mind the car was not running when I did this so that is why its a little low. Then I took out the resistor bridged the wires instead, did the same thing, ran power to the plug, and now it was obvious the fan was going faster. So the resistor works, the fan works. Now when I put the resistor back in the system just as before, and turn on the a/c the fan wont run on high speed, the car eventually heats up and it starts going on and off in bursts. Here is where it is wierd. So when the fan goes on in a burst, I check voltage before and after the resistor and its 13.4v, how is this happening? There is only power in that wire ( the thinner red wire) when the fan is actaully running. Yet when I go to test voltage just as before, there is no drop? What the heck is going on?The 30amp fuse isnt blown, is it possible that the relay is bad or something? Because basically what i gather is that the system is not calling for power to go through that thinner red wire, if there was power going to that wire then through the resistor and to the fan. The resistor is wired exactly where the old one was, and like i said if you bypass the wiring system and just run power directly to the plug it functions, but when the car is on and running something isnt working properly.

Can someone explain to me in dummy terms how the older type fan system is wired? I looked at the wiring diagrams but I dont know how to read them. What am I over looking?

 

I GOT IT!

So after looking at the wiring diagram for like half an hour, I checked the 30amp fuse for the low speed fan, Sure enough it was BLOWN. Such an idiot, when I tried to bypass the resistor the first time and bridge that connection i forgot that the fan would now be drawing 50amp not 30 amp, that is why it blew and that is why I was not getting the fan to turn on at low speed with or without the resistor. I dont have a resistor handy but Im pretty sure once I replace it I should be getting my low speed fan!

 

There's a spare 30 amp fuse in the relay box in the footwell by the driver's door, at least on my '06.

 

Last night I installed the Arcol resistor that I picked up from Mouser. http://www.mouser.com/ProductDetail/...XjsYM7uQ%3d%3d Everything went smoothly. Drilled and tapped the motor mount for the resistor to bolt to. I used ArticSilver© thermal paste between the resistor and the motor mount which is excellent stuff. After I wired everything in, I now have low speed fan operation .

 

well done, good to hear my solution is still going strong.....

cheers

Chris

 

I'd like to add my big THANK YOU to Chris for developing this solution. My low speed fan is operating just fine with the mod and I'm grateful Chris had the time and knowledge to share this with the rest of us.

Eric

 

Eric,

you are very welcome, glad to help!

Cherrs

Chris

 

Ok, I have read the whole thread. Thanks Chris for your solution!

Now, I am not sure if my low speed is working or not. It's not very warm at the moment, 25F to 32F.

I have a 02/05 car (Feb 2005) MCS.

I just replaced my power steering pump and power steering fan.

1. When does the PS Fan kick in?

I tried turning on A/C, low speed does not come on right away. A fan did come on after running for a bit and then went off. Not sure if it was low or hi as I don't think it sounded as loud as some people mentioned. And again, ambient temp is cool right now.

My A/C does blow cold.

I'm confused! I don't know if I should do the resistor trick or not.

 

Naw, pretty sure it was the high speed fan that kicked in. Went off, kicked in again. It was loudish. Now I have to decide whether I want a full fan or a resistor.

 

Went with the mouser resistor. 35 bucks shipped to canada. not too bad for a cheap fix! did anyone provide photos of the wires I am to splice into?

 

The discussion here is about the radiator fan, and the large resistor they use to create a low speed when only a small/normal amount of radiator cooling is needed.

That has really nothing to do with the separate fan used to cool the power steering.

 

I know. Look at the my other two posts. I have ordered the resistor. People have talked in the thread about the PS fan working in conjunction with the low speed/hi speed.

People have also talked about how the low speed affects the A/C. Your reply didn't even add any value, stop policing the thread.

 

Ah, the solution to that is simple.

You need to stop asking questions here, if you don't want anyone to try to offer any answers to them.

 

rhcp4life: Thanks so much for the schematic, and the link

 

I'm very glad to read this thread since I'm on my second fan, low speed failed again. Since the .33/100W is out of stock I bought two 0.68/50W. Cheaper too. Pics to follow, fan-side wiring only.

Vishay p/n RH050R6800FC02 - 0.68ohm/50W

 

I'm installing my resistor this week.

Bradley, do you check your fan to see when it fails? How do you notice it has died?