E46 electric fan not working(How I fixed it)

[@bmack287]

What the box on top of fan called i need to order one from fcp euro

[@TheLocalGent]

curious. i have no leaks, coolant has been bled properly multiple times over and over again, runs at correct temp (almost perfect) BUT my coolant light is still on :/ im lost for ideas & today i thought "could it be the fan switch" is bad. do you know if a bad fan switch can set off the coolant light? i know in other cars it can as its cooling system related.

[@3dward.v]

It’s most likely the sensor at the bottom of the expansion tank that is either disconnected or needs to be replaced if you lights stays on but your coolant level is good

[@TheLocalGent]

@@3dward.v I've replaced it twice and still stays on

[@mhperformance__]

I do not, sorry. Jump the wire together, if the lights goes off it's your sensor if it stays on it's something else. It is the expansion tank.

[@mhperformance__]

Found this response on E46 fanatics. I would Link but KZbin doesn't let me my messages get deleted. I put the original sensor back on and put a magnet up to it. sure enough, light turned off. I actually noticed the light is kind of buffered and it takes a while for it to turn on/off unless you cycle the ignition. Anyway, I pretty much narrowed it down to the tank and pulled the behr one and put the OE one I originally had in there back. It only had about 9k miles on it but I was being paranoid. Sure enough, original tank and the light never came on. I still have to wait for it to cool overnight and to see if it comes on during warm up (which is what the other one did) but so far no issues. I actually took my telescoping magnet thingy and put it in both expansion tanks. The OE, the magnet grabbed the float all the way in at the tippy top, but on the behr one it caught the magnet right when I put the magnet into where the sensor goes. I tried this on both laying on their side in the same position. If I had to guess, I think the float was put in upside down. Hopefully tomorrow when I drive it again and it warms up, it should be good to go.

[@howlingmedia4354]

I thought the electric fan was for the ,a/c condenser?

[@UnapologeticIslam]

It turns on anytime you run the air conditioner but that is not its primary function. It’s primary function is actually to maintain engine and coolant temperature. No, the clutch fan doesn’t maintain the coolant or engine temperature. The clutch fan is useless. If you don’t believe me, try running your e46 without the auxiliary fan and only the clutch fan. You’ll see that Idling and/or driving in stop & go traffic, your e46 will start overheating. Now do the inverse and remove the clutch fan and leave only the auxiliary fan and you’ll see the car will always maintain operating temperature while idling or in stop & go traffic with or without the air conditioner running.

[@baxtermason6909]

I believe that the electric fan is used for the ac condenser in cars with automatic transmission because you have two fans; for manual transmissions, there is only one fan and it's an electric fan.

[@davidalvarez6693]

Do you still have your E46?

[@mhperformance__]

Yes, I still have it.

[@PrinceRocky561]

@@mhperformance__ Ayeee

[@yasdsdas]

The link in the description is not working..

[@mhperformance__]

www.e46fanatics.com/threads/radiator-fan-coolant-switch-how-do-you-test.1109062/page-2 www.e46fanatics.com/threads/radiator-fan-issue.1298953/#post-18977792

[@BelieveMk-nj4fc]

Hie bro i have a fan problem i replace everything new but its not kicking

[@mhperformance__]

Sorry I didn't get notified of your question. Did you fix it? What do you mean replacement everything?

[@import4lifehaze217]

Did you switch you lower radiator hose sensor

[@redhill3248]

I have the same problem at the moment, did a full cooling system replacement hoses and thermostat and expansion tank and radiator, the only thing i didnt replace was the fan and it doesnt spin no more

[@mhperformance__]

The Electric fan should turn on at 204f, at idle. My expansion tank exploded. I know most would say the head is warped. It's been two years with no issues.

[@CZUNIGA36]

Thanks for sharing. .

[@jimiheil8007]

What is impa?

[@mhperformance__]

Is that what I said. I meant INPA. Is a BMW diagnostic software.

[@prophetpastorblack]

Auxiliary fan relay

[@geovp1984]

That is not aux fan relay, its a recirculation air sensor, that closes the vents when detects to much pullition outside and recirculate the air in the cabin nothing to do with the aux fan.

[@UnapologeticIslam]

Geovp is correct, however do not discard that air sensor… Your auxiliary fan will not run without it.

[@rondjeee]

Really? ​@@UnapologeticIslam

[@baxtermason6909]

@@geovp1984 you're absolutely correct...it's officially called an Air Quality Sensor...