BMW E46 E39 E53 AUX Cooling Fan Problem Not Working correctly Relay and Thermostat

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BMW E46 E39 E53 AUX Cooling Fan Problem Not Working correctly Relay and Thermostat,
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[@tedebare7874]

I have looked at several videos and you are the only one that did something different

[@ppgchris399]

Hello the problem was fixed by me changing the coolant temperature sensor (cts). The fan won’t come on unless that sensor is properly working. The (auc) air quality controller just controls the recirculation mode on the ac. Reads whether the air is bad or not. If that doesn’t work. The recirculation button won’t work properly. I hope this helps whoever is reading this. Godspeed.

[@unit3edkarnage]

Hey Nathan I was wondering if there was a quick way to test these before just replacing them any advice?

[@larrycampbell2500]

I did not catch where you said the relay was located and possibly that's what got it going. Do you know where the relay is located on the 4.4 l thank you Nathan

[@devinpyska6087]

One of the biggest issues with these bmw the 3 5 7 series with thise dash style. From 82c to 105c the temp gage sits at half.

[@lashawntinsley3407]

You mentioned both fuses were good. I checked the 50 on mine and it was fine. What’s the other fuse bc my fan still isn’t working after installing a new one.

[@scottleigh2444]

Is there a chance you could post part numbers on the fan relay

[@keating15]

Nathan i need help bad no air in vents at all ac or heat changed out fsu still nothing aux fab comes on when engine temp gets too hot but not with ac on?????

[@Bmanfresh]

My e83 has the fan speed on at all times. Stuck in high mode and it doesn't seem to overheat, but I've read a few things it could be the ac is overpressurzied or it could be a waterpump or it could be a sensor or could be something to do with the battery fuse block or a fuse/relay idk hopefully you have some insite... to be noted the car was crashed in the front right corner. The ac drier has a sensor on it and the accident did shear the sensors clean off at the connection point. Maybe that could have over filled the ac system? Or is there any sensors in the front right hand passenger headlight/fender I should replace that may have been messed up in the accident?

[@jaciobe]

@Nathans BMW Workshop when I turn my car off I get like an air sound constantly blowing from the vents through the bonnet.. cant feel air though. Would you know what's wrong because this video explains its overheating it's had so assuming it could be that. But it's draining yhe battery every time it's turned off till it's dead.

[@ItsTemLock]

Two fuses? I looked at my E46 manual I thought only fuse #37 was the fan fuse. What’s the other one?

[@kevinfraser640]

Sir, did you have engine codes for the sensor and the relay? I have this 2006 BMW X3 and have replaced everything. Radiator thermostat water pump upper radiator hose heater vent. And the fan suddenly isn’t turning in it blowing coolant out of the new reservoir tank. But zero codes. Overheating not good. I’m thinking sensor and relay like you possibly fan too but no codes, thanks Kevin in New Jersey

[@starrchandler1513]

Hello, I have a 2006 BMW X5 3.0 and I’m getting codes e3 and e4 permissible range exceeded fuel trims. Can you tell me what this? How do I fix it?

[@havahziggy]

Nathan I don't mean to bother you to much, but where would I look for the air in the system and find the strip boat you're talking about I'm really don't know much about cars

[@albeee8030]

Nate do you have info upon the A/C Condenser Radiator Cooling Fan w MOTOR the big black box switch i know where the one is located in bottom radiator hose. Mines twists a bit too far in my opinion so i wanna change it as well thanks brotha tyrone for 2006 E53 3.0i SAV i have. Im waiting for parts to arrive now, and it hasn't gotten to kind of weather i wanna be in to get on the job of checking things out from diagnostic standpoint to looking behind glove box etc i don't even know how to drop my glove box..lol and i wanna check these computers too i think in part why its not getting any power may be due to the water leak i previously told you about. I saw some things under the passenger floor board area underneath glove box i believe is where some of computers are housed so i plan to pull whatever's there from all the rain that leaked into vehicle via the A Pillar on passenger side and that leaked onto the on board monitor from ceilings center console that damaged the radio...it works you cant see anything on screen and can only control volume via steering wheel. I wrapped a blown fuse with piece of wire n put it in its place the monitor then lit up orange color when i did that so i think.there is a short or some how too much power is being diverted some where because i put new fuse in rear for navi etc each time i do i automatically blows that fuse only no other fuses are blown which its the 5 amp fuse. Like i stated i got general basis on what to dive into here trying to wait til we have better nice weather on day to day basis. Its bonkers in NY brotha i will either fix it or fuck it up one lol just kidding on fuck.it up part.. im learning to be my own mechanic

[@A.N.TInvestments]

Sooo, am i suppose to replace my radiator cap. my car overheats after staying still for maybe 15 minutes.

[@antoniodicappo403]

We've had similar issues in the past. Solved as you've explained so can confirm your methods. This is very important because if you 'cook' an engine and blow the head gasket, it's a damn pain, let me tell you. Keep 'em coming Nathan :)

[@samalfakir5463]

it turned out to be the thermostat ... i initially ruled it out because it was 2 years old (after market junk however) .. i bench tested it and it failed.. case closed.. the Nathan guy is a fraud

[@dougdileo4727]

my 2005 x3 2.5L normal gauge temp but fan comes on at 172d. changed coolant temp sensor was a drip from oring but still with new cts it still kicks fan on at 172d ??..could aux fan relay cause this issue

[@kribar96]

Hocked my auxfan up to a battery. 4wires, 2 bigger than the other. Brown and blue/black "i think". The fan did turn on, after trying back and forth with different wires it stopped working. I guess the last resistor went too. Only managed one speed with which i think was full.

[@anthonysteelemusic]

That little black box is the only thing that has not been changed on my cooling system. everything is new. Thank you. I will post an update for the benefit of others.

[@akexbyidr6252]

Did that box ever worked?

[@samalfakir5463]

Did changing AUC (little black box on top of fan shroud) help any ? please share ..

[@darrenakdeacon]

Hello?

[@frankarandajr3138]

great vid Nate

[@ferv88]

I just replace the aux fan on 2003 x5 and no turn on unless disconnect the ac pressure sensor ?

[@AngelFlores-rh3ef]

I got a 2004 bmw 330ci and when i accelerate that shit louda asf and i feel like it could be running smooother any tips

[@tracierainey8200]

what is the part number for the fan relay. I've replaced everything but the fan still isn't working even with new fan and temp sensor.

[@sabahameer2620]

My fan always on High from first start on cold in the morning till the end of the day it won't stop at all what should I check ?

[@Blu3Ey3s888]

Cool,thank you Nathan! I enjoy watching your E46 videos.

[@MrBlake-cz4km]

On my 2004 chevy venture, the cooling fans kick on when the engine is about to overheat till it goes to about half then they stop, they are on all the time when the a.c. is running. And I also replaced all the relays for the cooling fans so I don't know what the hell is going on

[@Matthewleiva09]

My cooling fan on a 99 540i turns off when I plug the Temperature Sensor , and d only way it comes back on is if I pull d sensor out d Hose and plug it back without plugging the sensor. Stay on like that with no problem. Can I keep it like hat? I put a new sensor and it those the same thing.

[@sabahameer2620]

Thanks for sharing ❤

[@ricardopelc-wesoly3483]

What fixed it, what did you replace.

[@sickw204]

My snowflake won’t turn on it worked before but now it won’t turn on neither does the front window defrost everything else works fine do you know what it is?

[@Darksaige]

I never checked my relay so guess that's next. Oh..... I've already replaced the fan. It wasn't a waste because I wanted to swap bumpers. But my fan still isn't coming on

[@Bmanfresh]

Will a e53 (x5 ) fan assembly fit a e83(x3)

[@JackmeMe]

I thought the fan only came on when it had to, not too sure but my car only has the fan on (and its occasional) when it reaches operating temp or the a/c is on. Think this is just to keep the car at the steady operating temperature though. I've had long drives in my car (2 hour drive for about 120kms) and I wasn't observing the fan when I reached the destination but the car was steady operating temp, even with a/c on.

[@lindyyow6540]

Thanks this helps. My 2003 X5 4.4i has been acting screwy. The AC fan is fine when the engine is cold but when hot, the blower just stops blowing. If it cools down or we turn AC off for a while, it will be fine for maybe 10 min. And yes I noticed I was using a lot more coolant for the engine. Perhaps unrelated is my radio Aux signal sometimes gets shorted out in the heat and jumps to the radio. Any ideas?

[@NathansBMWWorkshop]

The ac fan inside the car or the aux fan stops blowing?

[@dragoslavristic6658]

Great video. Not specifically related to this, but, do you have any idea how to return panel with display to panel with buttons, so that the small copper contact parts, not pops out of their socket?

[@NathansBMWWorkshop]

+dragoslav ristic I will need some more details , i couldnt follow you on that one

[@anthonysteelemusic]

Hey Nathan. I have a 2000 528i. Here is my issue I can run it all day sitting in my drive way with the heat on and it will not overheat. I drive off and it doesn't over heat. Whenever I turned on the A/C and come to a stop that when it over heats. The fan does run when I turn the A/C on but I don't think that it comes on when the car temp is high. If i unplug the temp sensor the fan will spin full speed. I take the thermostat out ant it still did the same thing. What could I be missing and what is the little black box on the fan shroud for? Thanks you

[@grumpyoldrockers1048]

Donovan, did you fix it? If so how?

[@dlburnett6098]

My 528I My temperature gauge do not work the longer it drives the better it sounds My antifreeze is coming out of my radiator cap please help

[@davidkisdk]

Hi mate mine its always on every straight after morning start.

[@anthonysteelemusic]

I hope that was clearer

[@grumpyoldrockers1048]

Nathan, at idle my 00 528i will get hot, no Aux fan. While moving it's fine. If I'm at idle, I turn the heater on, engine cools down but Aux Fan won't come on. It ONLY comes on when I turn on the AC. What's the dealio?

[@init4u222]

Andy Micheli if an automatic it's your fan clutch. The 1 that spins onto you water pump.

[@tvdigi]

Hello Sr.Nathan i have the same problem with my 2006 x5 e53 3.0i that fan sometimes turns sometimes not at all if it stays in idle it will overheat should i replace that switch an the black box? whats the name of that black box? here in Chicago looks like we are not going to need ac this rest of the year but i whant to get this issue fix. Thank you Sr.for the video is great and very informative.

[@NathansBMWWorkshop]

Replace the black box first , search ebay for "bmw aux fan sensor"

[@tvdigi]

Thank you Sr.

[@samalfakir5463]

2005 BMW 330i E46 runs hot on idle only .. AC on .. electric fan comes on full speed only .. i changed fan coolant switch (Temp switch) no change .. disconnected the AUC (no change) .. changed fan clutch (no change) .. the electric fan works full speed only .. inside temp gauge goes to 3/4 way up.. if you rev engine to 2000 RPM .. car cools back down and AC comes back cold .. no white cloud out the tail pipe.. no milky oil... can the electric fan running be running too fast ? there are no leaks.. pressure tested good.. please advise.

[@samalfakir5463]

it turned out to be the thermostat ... i initially ruled it out because it was 2 years old (after market junk however) .. i bench tested it and it failed.. case closed.. the Nathan guy is a fraud

[@havahziggy]

Nathan I have a 3:25 XI 2004 BMW it overheats but I turn the air conditioner and the fan comes on but it still doesn't cool off my car can my fan be bad

[@NathansBMWWorkshop]

The fan could not be going to the second speed, but the fan is only going or affect it if your sitting still, if it's overheating while driving it could be air in the system or the head bolts stripped

[@ahmedaldayyeni501]

Hey Nathan would you please help me .. i have a 2004 BMW x5 3.0i engine gas and the aux fan used to work fine and engine never overheated and the air condition blew nice cold air. Recently the fan stopped and the engine started over heating in traffic and the AC is not blowing cold air. Where do you suggest me to start digging to get it to work and how can i give 12V to my fan to check if the motor is dead or not. Thank you

[@jessesantos4442]

figure it out?

[@lindyyow6540]

I kept the old resistor because it was > $70 through my mechanic It seemed to help then but now it seems the blower cuts out when it gets hot. How do you know if the resistor is bad? My mechanic was quoting me $1100 for the fix but he wasn't sure if that would fix it.

[@NathansBMWWorkshop]

Im almost positive its the resistor if its getting hot and shutting down, a new oem behr is $38 off ebay, i might have one here but i will have to look and see

[@anthonysteelemusic]

Thank you. I would appreciate it. I have spend every dime changing out everything else.

[@MrHengDoItAll]

Hey Nathan , Mine E36 I was test my fan working find. and I replaced Coolant Temperature Sensor and start engine with AC on 15min , But am not see fan have spin. Do you have any idea something els ? thank you

[@NathansBMWWorkshop]

+Raksasok Heng Check the fuses behind the glove box.

[@datadrianLAX]

which fuses? obviously the fan fuse.. but are there any others that may affect the fan not coming on?

[@NathansBMWWorkshop]

No just the 2 o3 3 huge fuses, the other problems could the a bad fan or fan resistor or a bad relay

[@davidhorton9194]

Hi NathanI got a 2004 bmw 745i. I changed the upper timing belt tensioning bolt, an now my car want start. it seem that the bolt that I took out was missing the bottom spring tip for some reason. When I put the new longer bolt in the chain rattled, so I took it out an replaced it with the original shorter bolt with no tip on it.But now the car want start. Do you know what could be the cause?Thank you,Dave Horton

[@NathansBMWWorkshop]

Hello you have the n62 , are you talking about the timing chain tensioner?

[@MindHunger]

A source told me that the electric fan on the M54 turns on at 100°C and off at about 95°C, but if you disconnect the connector at the electric fan sensor on the bottom radiator hose the electric fan turns on at 100°C and off at 85°C. I can't confirm this anywhere, but if its true its an easy fan hack to increase cooling. Do you know if this is true?

[@anthonysteelemusic]

Hey Nathan. I have a 2000 528i. Here is my issue I can run it all day sitting in my drive way with the heat on and it will not overheat. if I drive off it will not overheat unless I turn on the A/C. Whenever I turned on the A/C and come to a stop that when it over heats. The fan does run when I turn the A/C on but I don't think that it comes on when the car temp is high if I turn off the A/C. If i unplug the temp sensor the fan will spin full speed, that tells me that the sensor is working. . I take the thermostat out and it still did the same thing. What could I be missing and what is the little black box on the fan shroud for?

[@NathansBMWWorkshop]

Its the relay that is the problem, which is the little black box on the fan shroud.

[@grumpyoldrockers1048]

I have same model and year, aux fan ONLY comes on when AC is on, NOT when I'm at idle and then the temperature gauge goes up. Turn the heater on, and it cools down... While drivind (no heater no AC) cars stays at perfect temperature, Relay box? Cause it doesn't come on at idle and car gets hot... I'm lost...lol

[@miyu7i]

Hello Nathan. I'm having some issues in my car. It's an e46 330i model year 2002. My car has single electric fan because it's a manual transmission and my AC and electric fan aren't working. I checked for codes and found that my thermostat not working so I replaced thermostat and the temp sensor (I suspected this sensor as well) on the lower radiator hose. Unfortunately the fan is still not working. I believe that the fan is not getting signal from the ECM to operate because when I connected the fan directly to battery it worked finely. Also AC gas system must be fully charged in order to fan to work. I'm planing to put a new fan and recharge the AC system. Please help Nathan. Kind regards and all the best for your work..

[@NathansBMWWorkshop]

It could be the fan, the fan on those have the resistor box on the fan itself that could be bad

[@miyu7i]

+Nathan's DIY Garage thanks for the quick reply. I'm hoping to charge the AC system first because it's cheaper😂

[@Yophillips3272]

Seems like all these BMW's eventually will have the same problems, but no clear answers lol The 50 amp fuses, not sure what they go to unplugged both, fan still had power and blower fan still had power 🤔

[@SleepyJoe408]

⁠hi mate. I own a bmw x5 2004. I’ve replaced the condenser , compressor, radiator fan, condenser fan, and expansion valve and still don’t have COLD 🥶 air. The most it gets is “cool”. What am I missing? Also what’s the yellow light in your dash? Mine has that same light on.

[@Zairn12345]

Did you clean the pipes before installing the new stuff? You might have introduced junk from the old system in the new items without a proper clean out.

[@SleepyJoe408]

@@Zairn12345 I would like to think I did. At this point I’ve done it all except change the heater valve. I’m thinking about replacing that in a couple months before the summer heat waves start coming

[@lindyyow6540]

I already changed the resistor 2 yrs ago. Aluminum fins, had to take the glove box out to get to the back of the dash.

[@NathansBMWWorkshop]

Did that fix the problem then? Its either the resistor again or the blower motor itself and you better hope its not the motor because that will be a huge job

[@67mustang351w]

hey nathan, hope you can help me, i have a 01 bmw 540i and it has a loud aux fan noise it sounds like a airplane, y changed the thermosthat, lower hose cooling sensor, and water pump sensor, but the noise is still there and loud, please i need ur help how can i fix this issue, THANK YOU

[@Xdbd1]

@@67mustang351w auxillary electric fan, or engine mounted fan? My engine fan was roaring up due to the fact that that's what it's supposed to do in 100°F weather. MY issue is my electric fan is only receiving 0.3v instead of 12.0v

[@stevenburke5494]

That sounds like the viscous fan has seized up hence running at engine speed can break the plastic fins off the fan and dent your hood and rip up your hoses. Mine seized yup sounded like a semi truck taking off from a stop

[@mavricxx]

Hey Nathan, I'm having the same issue with my car all of a sudden, but I can't find a freaking video on where to or how to access the fuses you mentioned behind the glove box. Could you do one to show where they are and what they do? Thanks buddy!!!

[@init4u222]

Rene G. Solis it drops down from the top of glove box on my BMW. Has 2 plastic clips you spin and it drops down then comes with a diagram to locate specific fuses.

[@stevenburke5494]

On my 2003 e39 530i they are under the glove box accessed through the lower panel required contortive position to reach up in there

[@dicappa.7298]

Hello Nathan, I own a 535i e39 M62b35 v8. I recently replaced waterpump, thermostat and flushed the coolant, got a new coolant tank, cap and coolant temperature sensor. Now as I go and drive more than 15min, the coolant tank starts boiling and overflows, any ideas? (Hoping that’s not a head gasket)

[@fortniteboss2837]

If it's head gasket you should see oil in the coolant like sludgy white stuff or white smoke out the exhaust. When you flushed the coolant and put the new coolant in. Did you bleed the system because you might have trapped air in the coolant system causing it to over heat. Bleeding is very easy takes 5 minutes

[@fortniteboss2837]

Also take your oil cap off make sure the colour isnt a white colour where the oil and coolant have mixed.

[@dicappa.7298]

@@fortniteboss2837 the problem is it did this after coolant beeing flushed already, maybe I did it wrong and there’s still some air..

[@BarbaritoAdolfo777]

AUC is not a relay Automatic recirculated air control (AUC) is an additional feature controlling the automatic operation of recirculated air. The AUC feature uses an oxidizable gas sensor usually mounted behind the right side of the radiator or the right side upper portion of the fan shroud (samples air quality as coolant fan pulls across the radiator). The AUC sensor contains a combined heating element (powered by the IHKA module) and a gas sensor. The gas sensor requires heating to work efficiently. The sensor produces a varying voltage based on air quality (concentration of hydrocarbons, NOX, SOX, and CO). The voltage increases as the air becomes more polluted. After it reaches a preset value, the IHKA closes the fresh air flaps. To prevent glass fogging, the system has built-in time limits: 3 minutes when heating and 12 minutes when cooling. With normal air quality, the AUC sensor reads about 0.5V. If the AUC sensor voltage increases to 3.0V, the ventilation or fresh air flaps will close (0%). At about 2.5V, the fresh flaps will read about 20% and 100% (fully open) at 2.4V.

[@samalfakir5463]

does the AUC makes engine over heats on idle if faulty ?

[@BarbaritoAdolfo777]

@@samalfakir5463 no

[@itsmerz]

i have a 1999 bmw 328i and after i turn off the car and while i have the car on a really loud fan from the front hood is on full power and it doesn’t turn off until i unplug the electrical plug.

[@itsmerz]

can you please give me some info on it??

[@1Devin78]

Thanks

[@ripdapip5000]

@ Nathan's DIY Garage is this a e39 because there is a switch on the actual side of the radiator on e39 that is easy to replace that controls that fan

[@JesusTorres-cv2fv]

Tell me more please?

[@bobsmithinson2050]

If you couldn’t tell this was an e39, I kindly ask you to put everything down, and slowly back away from BMW’s forever.

[@orlandofarini1350]

Nathan I see the traction control light is on!! Same on my car and it doesn’t have acceleration, do you have a video for that??? I would really appreciate

[@mickiblueyes4u]

were you having any transmission slippage? I believe that is limp mode. I had to replace some transmission solenoids.

[@ForidKhan123]

Hey guys, I changed the radiator on my E46 330i along with the expansion tank, HEPU water pump, Febi thermostat, Gates upper and lower hoses, Febi coolant temperature sensor. But the fan no longer runs in low and medium mode. When it runs, it’s always at full speed. Sometimes the fan doesn’t turn on and the needle goes past middle. I replaced the temperature sensor from Febi to a Hella but no difference. My cousin even used INPA to run the fan at different speeds and it works perfectly. I have exhausted all efforts to find the problem. Any help would be much appreciated. Thank you!

[@southernfoods7302]

Does your car smoke on the passenger side with a burning oil smell? I think I could be experiencing something you are with the fan deal plus having a overheating smoking issue

[@jakofall79]

What sensors did you check in the glove box for that issue

[@johndaniel3474]

The fuses for ac what sensor will be in the glove box lol

[@robshea7984]

The part you're calling the fan relay is the AUC sensor, which has no connection to the aux fan. If you have recirculated air set to "Auto", the AUC sensor temporarily turns on recirculated air when it detects hydrocarbons, etc. The little plastic flap on the opposite end of the connector allows air in to be tested.

[@NathansBMWWorkshop]

I am not sure what connection it has to the aux fan, but the fan absolutely will not work without that box, let me be specific, it will work with the. ac on but the fan will not come on with the ac off when the car is overheating, if you plug that little box in when the car is hot it will instantly turn the fan on, if you unplug it the fan will instantly turn off, I urge you to go try it and see what I mean.

[@Sroor2023]

@@NathansBMWWorkshop 😁 Really funny this box has Nothing to do with the fan its unplugged for years and my fan working like a charm its Just as mentioned above if you dont air from out side or if you want your car to be vented Automatically when its needed

[@bobsmithinson2050]

Sroor9001 so which one of you guys is right? Also, at what temp (Celsius) is the newer 3-pin (pwm) fan supposed to turn on with AC OFF? Been searching for DAYS

[@samalfakir5463]

@@NathansBMWWorkshop i tried it .. AUC has no effects on the electric fan

[@jarvishamill7717]

Actually it does control the cooling fans. AUC does not stand for Auto Recirculated Air...That would be ARA, lol. AUC= Auxilary Cooling fans and for some weird reason it does also have something to do with the recirculated air.

[@anthonysteelemusic]

is there a way to test if you have a bad relay?

[@NathansBMWWorkshop]

+Donovan Scarlette I'm sure there is a way to test it but if the fan is not using the second high speed the it's the relay for sure, I might have one here if you need one

[@steezymoney1874]

@@NathansBMWWorkshop so your saying if my interior fan work but not the aux cooling fan then its the relay?

[@gusto8069]

The what relay?

[@brendam455]

I missed it after I need to take the bumper off what you change

[@gusto8069]

the whole fan

[@Alex-ti3uf]

I have the same issue, what I did was to just disconnected the AUC sensor and fan works (Running steady). But I have to changed the AUC Sensor for permanent fix.

[@bobsmithinson2050]

Alex you disconnected the AUC sensor or the one on the lower radiator hose?

[@LIVdaBrand]

Good to know!

[@kevinfraser640]

What is the AUC Sensor

[@gabrielito88]

Hi, my car is overheating every time i turn on the ac, but only if i drive longer than 1 hour. So i checked the aux fan when the car was overheating and it was turning. Also replaced the coolant sensor with the switch but didnt solve it... Maybe its the fan itself that is not turning fast enough? Any ideas?

[@NathansBMWWorkshop]

it could be, the fan has 2 speeds maybe the second speed is not working right, the little black sensor on the fan shroud controls that

[@gabrielito88]

I ran the aux fan test with DIS57, the test consists in activating the fan at different rates. So its not 2 speeds but variable speed. It ran 25%, 35%, 55%, etc. The problem is that the actual speed didn't change at all. So the control unit must be bad. That sensor you refer to is the AUC sensor (Automatische Umluft Control). The control unit is attached on the aux fan itself but i don't think it can be replaced...

[@miamidudeful]

How did u fix it

[@heavyseven88]

my fan dosen't move my car over heats so I stop. Mechanic this week but I think it's the sensor just got more antifreeze. ..

[@victoralonso7281]

James Newsome what SENSOR?

[@stevenburke5494]

Lower radiator hose coolant sensor is my guess

[@jimmyjimmaay]

man do you see that ignition leak on 3:46 on 5th and sixth plugs under your cover! shock therapy right there buddy.please check! might be your problem also.

[@bobsmithinson2050]

Kilo TheDog Ragzilla dude, what are you talking about?? I see some rain water vibrating from the engine running but that’s it..you had me watching that part of the vid over and over again but I don’t see what you’re talking about

[@texast1311]

Can u show us which one is the relay ??

[@samalfakir5463]

There is no relay..

[@hmongkieyaaj1491]

Okay so I noticed my aux fan would not work every time. I plugged in my Creator c310 and I got a code for electronic fan. I then erased the code and all is well now. Fan is running good.

[@GurillaRon]

I changed my radiator fan on my 96 bmw 318ti and it works but now my car turns on and then Boggs down and turns off. But it worked fine before. Has anybody ever had the same problem? I stumped!

[@schylarichey5421]

bought new fan for 98 528i automatic and doesnt even come on thinking about trading it for a chevy lol seriously these german engineers were high or something

[@orlandofarini1350]

Schyla Richey do you think your old fan works?? I have the same car

[@Ryukachoo]

just now getting this issue, purchased a new aux fan since my car's at 145k miles and going by records i don't think it has been replaced. knowing my luck, i'll replace it and it still won't work :/ my diagnosis so far has been that it literally never turns on. not when the car's hot, not when i turn on the AC, it never spins also i replaced the temperature switch on the lower rad hose not two months ago, so that's probably not it

[@ripdapip5000]

did you ever figure yours out? Did you end up just replacing the fan? I have a 2001 e46 330ci and the aux fan never comes on now, overheats after 10 min of running...sad day....i had found that my three prong connector(for the aux fan) from the main harness had somehow melted at the end, have yet to try to track down the rest of the lines to see if they crossed anywhere else

[@Ryukachoo]

Nightstalker907 Yeah, new fan fixed it immediately, the new fan is quieter too

[@ripdapip5000]

Sweet will be ordering mine next week, tired of overheating for no real reason.

[@miamidudeful]

@@ripdapip5000 did the new fan fix the problem as well ?

[@obiwan2143]

Does this cause the car not to start ?

[@gusto8069]

no

[@memohernandez7777]

Nada , que no arreglaste el problema de el fan ...

[@sosagrimeztv4728]

$300 worth of labor ?

[@DriftSpec.]

I had this problem for years, it will only climb when im in a drive thrue, or at a stop light, i replaced everything but the fan, that was the culprit in my case. also if you see your gauge climbing past half, blast your heat and it cools down almost instantly

[@lindyyow6540]

AC fan inside the car. Blower is intermittent.

[@NathansBMWWorkshop]

Probably the blower motor resistor going bad and needs to be replaced, you should be able to get off ebay for around $20 and install it yourself

[@bmwchannel7209]

That is not a fan relay. That is the AUC - Ambient air sensor related to the air conditioning settings. Senses air quality. Has nothing to do with the fan or any relay.

[@kevinfraser640]

Please help me, please, I’m at wits end. I can’t find the smoking gun. Coolant system 2006 BMW X3, changed water pump thermostat upper radiator hose, radiator , heater control valve, overflow bottle and rad cap. The car is overheating. I have Zero codes. The fan isn’t staying on when the car is shut off and over heated. Again no codes for lower radiator hose sensor or relay. Doesn’t seem like the thermostat is being told to open so there is flow. I’m at the end of my mechanical rope. I don’t know what to do next thank you Kevin NJ

[@bmwchannel7209]

@@kevinfraser640 - when you changed the lower hose, did you replace the sensor attached to that bottom hose? It may be malfunctioning. Also, did you bleed the system properly? Bubbles will cause overheating.

[@brendam455]

you said no more leaks? do you mean oil leak? my coolant sensor was bad and I nosiest that my oil level went down but I had no leaks under the car... I am kinda confused... I don't know how is it buring oil? can anyone help me before 9/20/16 please!!!!

[@NathansBMWWorkshop]

its normal on most of these cars to burn a quart every 1000 miles or so, if it went down quickly check the dipstick 0-ring, they are common to leak

[@76Bourne]

If your car is losing oil and there are no leaks to be seen and there is no smoke coming out of the exhaust... Check your pcv valve and or your oil separator valve. I cant agree with Nathan on this, I don't think losing oil is normal but I'm no expert either.

[@jason.arthur.taylor]

FYI, the temp gauge doesn't get "a just little over" halfway because the needle isn't linear. It is controlled by a computer program which has a special idiot buffer. Typically it goes over 1/2 at 115 C. So from 75C-114C it will be at exactly 1/2. I removed my buffer because I don't like companies lying to me, so I know what I'm talking about. Psychologically speaking, what's happening here is people are assuming it is linear, so they correlate the amount of time the temperature gauge is above 1/2 mark, and say when it gets just a little over instead of when it suddenly jumps way over, which is actually what happens if the cooling system fails. There's almost no time before the emergency leak system (radiator cap) would be activated.

[@danielzambrano180]

What'd you do to remove that buffer? Funny enough the first car I ever overheated was a bimmer.... Didnt know it was overheating until it was too late!

[@bobsmithinson2050]

How did you remove the buffer? Through coding? INPA?

[@orlandofarini1350]

It happened after mechanic replaced all 4 wheel speed sensors and brake pads, came back to the shop, reinstalled all sensors but the light still comes up, Ps; the brake pads sensors didn’t fit so they are probably discpneccted

[@getitdonegarage]

Nathan isnt very good at responding to subscribers

[@JackmeMe]

I thought the fan only came on when it had to, not too sure but my car only has the fan on (and its occasional) when it reaches operating temp or the a/c is on. Think this is just to keep the car at the steady operating temperature though. I've had long drives in my car (2 hour drive for about 120kms) and I wasn't observing the fan when I reached the destination but the car was steady operating temp, even with a/c on.

[@NathansBMWWorkshop]

+Jack Right it comes on when the ac is on and comes on to regulate the engine temp, i believe it has 2 speeds for that