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How to test the rad fan

5356 Views 18 Replies 4 Participants Last post by  swampX3
Hi all,

just after some help on testing the rad fan on my x3 3.0d. The car got hot the other day while stuck in traffic but I didn't notice the cooling fan kick in. I've tried putting the Air con on to trigger it but nothing. I've now removed the fan from the car but struggling to get any luck from it by adding voltage to it.
Is there a way to put some power into it for a test.
Thanks in advance
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good FESTCHIVE tips on testing/activating stuff from your laptop

home in around posts 36-39 wishes
Your a true star, thanks for the help
FESTER boggie fan shopping in UK experience

this might help any shopping you have to do from the UK

see around post 12 etc

Boggie Boggie is offline
Location: Worksop, Notts. UK

Join Date: Jul 2015
Posts: 6
Mein Auto: E83 M Sport auto
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X3 Cooling Fan not working
Hi Swampx,
I decided to have a look at the fan assembly. As you say, it is very simple to remove it after taking off the airfilter housing and inlet duct complete with Mass Air Flow. 2 screws to remove, it unplugs and it just lifted straight off.
I tested the supply voltage with my multimeter and there was 12 volts at the supply side of the plug from the battery.

I removed the fan assembly and put 12 volts across motor side of the powercable, but the motor did not run, so I suspect it is the motor

There is another sensor mounted on the top right of the fan assembly(looking from the front of the car), which the chap at the BMW shop said was the aircon sensor. ( it loked like a small microphone with a mesh coverI cleaned this with brake cleaner but wasn't able to test any further. Not sure but I think this sensor links through the aircon switch.
I must buy myself a Bentlu manual as you recommend!

I have taken the precaution of ordering a raplacement fan from one of the BMW dealers in the UK who run an online shop and were able to give me a 20% on-line discount. It comes with a 2 yearwarranty direct from Germany, and If I can find some other reason whythe fan isn't working then I can return it and get a refund within 14 days.
I'll have a look at other posts and your troubleshooting guide and see what I can do.
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Ah good reading, I personally think my issue is fan related too, looks like a common issue and not one anywhere from a breaker!!!!
Thanks for your time
budget coolant fans ????

can y'all get budget aftermarket fan as shown in the link .....possibility if funds are tight ????.....also .....go by part number during search cause these are used on many different makes and models
Managed to order a new fan from car parts for less for £265 delivered, hopefully this will solve it. I'll keep the thread up dated for future reference
Just to update the thread my new rad fan solved my issue and now works with the air con switched on, hope this helps
OEM or aftermarket etc ???

great job on fixing the fan

please post the brand and part numbers for the next FAN problem searcher wishes
Good point.

It's a frigair unit, made in Taiwan 0502.2004
Bmk -0105N

Thanks and good luck
FRIG AIR coolant fan pic

a pic of the BMW aftermarket fan from frig air attached


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Hi Swampx3

Will this part work? I am worried there are multiple versions of the fan. Are they specific to the engine type (petrol/diesel) or size?


some folks have used them

I would only buy a non oem supplier fan in a pinch like you seem to be.....BUT ....some of the festers have had success have to be certain of your part number and maybe email one of the festers in the UK that said he bought one

meanwhile keep beating the bushes for a good oem fan supplier
pull down screen shot for private messaging to tibbles

below shows the pull down for sending an email to tibbles who lives in UK and purchased a fan


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Worked fine for my 3.0d matey. Hope that helps
Testing Rad fan.

I would like to add my issue here also. This is my first post so please be kind... 2008 X3 with a 600 watt fan that does not rotate. Turned on a/c no rotation, checked power at plug, checks good. Pulled fan out (which was very easy) used a power supply on fan an still no rotation. My question is, what does the smaller 3rd wire do? Does that have to provide an input in order to run the fan? Reading other threads I'm almost sure I have a bad fan but that 3rd wire is giving me cause for doubt. Also, can you use a 400 watt fan in place of a 600 watt? Why the difference in fans for the same motor? Thanks for you time. Input very welcome...
read post 2 and 3 above

>the fan wiring contains wires/wire that sends control voltage/signal to the fan electronics

>go thru the fan start test procedure

>you can rig up a lower/higher wattage fan with its own relays and switches and poboy it BUT there'll be no control from the engine computer (called a dme by bmw) like with the original

> best bet is to get organized with the software to do your own activations of components and get the wiring diagrams etc...see example wishes

firebull has just replied to a thread you have subscribed to entitled - E-Series Standard Tools & SP-DATEN: Software Download Links - in the BMW Coding and Programming forum of Bimmerfest - BMW Forums.

This thread is located at:

Here is the message that has just been posted:
Hi Shawn!

Can you please help me too?
I need the software for:
Z4 35is - E89 Series Built 2010 and 2012.
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bad wiring too

#14 Report Post
Old 05-27-2016, 02:02 PM
Tmurf Tmurf is offline
Registered User
Location: Ny

Join Date: May 2016
Posts: 5
Mein Auto: X3
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I got the fan fixed. It was the signal wire at the main plug for the fan. I tugged on it and it pulled right out of the connector. The insulation was intact but the wire inside was green and disintegrated. Ran a new wire and the fan works as it is supposed to now. Thanks for all the input ! Guess it's always good to check the simple things before replacing expensive parts !
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