air cond question
 

hi, I've had the slow coming on problem with my A/C for a while now, usually comes on within 5 - 10 minutes, and once working keeps working all day.

however yesterday when leaving work in 32c temps i noticed that the A/C started normally then at each of the four sets of traffic lights i have to sit at before getting onto the motor way at each light the A/C stopped working, got progressively warmer until just hot air blowing.

although when on the motorway all was good, and today its working good

when i got home i left the car running opened the bonnet ( hood) and the electric fans were not running.

there appear to be two fans in front of the radiator, a very course bladed one closest to the rad and then a less course bladed one directly in front of that,

the car doesn't over heat at any time the coolant is fine the expansion tank is ok.

in other vehicles I've owned as soon as the A/C kicks in the electric cooling fan also starts.

can anyone shed some light on how and when all theses fans should be operating

many thanks

any ideas, on when the a/c cooling fan comes on

Might help if you posted which model/year/etc. of vehicle you own.

I can say it's not the 4.8is because that one only has 1 electric fan.

If not a model year...how about letting us know which model/engine you want us to make suggestions about? Is it the

1. X5 3.0d (M57)
2. X5 3.0d (M57N)
3. X5 3.0i (M54B30)
4. X5 4.4i (M62TUB44)
5. X5 4.4i (N62B44)
6. X5 4.6is (M62TUB46)
7. X5 4.8is (N62B48)

Zulu95 raises a very important point for all those who don't have their model/model year included in a signature...or who don't include that info when posting if they haven't created a signature.

E53 X5s are NOT all the same from 2000-2006...there were some important differences in production thru the years that help us to help you better when trying to answer questions and make suggestions. Provide enough information that will allow us to give the best answers we can. :)

yep sorry guys its a 2005 3.0d diesel, and ive had a look today and i was wrong there is only one fan in front of the radiator, ive disconnected the connector to the electric fan and there is 3 wires going to it two thick and one thin ( black)

seems the two thick are positive and a negative, i put a meter across it and have 12 volts
(13.6 when motor running) im reasonably sure that either the fan has died or that there is some sort of heat sensor that is not working, im thinking of that thin black wire.

can anyone shed some light on how to get the fan assembly out??

there is also a small box with a wiring loom heading into it just above the fan connector

sitting on the shroud for the mechanical cooling fan.

i guess what i need to know is a/ how to get the fan out and b/ is there constant power to the fan and then a control circuit to switch it on and off???

any help will be much appreciated, this thing seems very involved.

thanks

Not sure how to take it out on your car. Our single fan is inside, infront of engine.

Based on previous threads that black wire is a pulse wire. That is what triggers the fan to kick on. But, what I suggest you try is a bit different. Take it to a good AC shop and have them check how much refrigerant is in the system. Yes, freon pressure and that fan working are directly related.

Perusing thru the online TIS...it looks like the bumper needs to be removed before the aux cooling fan can be removed. But the front bumper removal instructions don't look that difficult either (there's instruction for that too at the TIS online site).

Below are aux cooling fan & radiator removal instructions for the M54/M57/M62 engines used on the X5 (see how important model details are? :) ). BTW...the links along the top of the page are live...so you can click backwards to see how I navigated to these DIY instructions...as well as checking to see if there are other TIS instructions you may need.

Radiator removal instructions:


Aux cooling fan removal :

Ok the bumper removes in 5 min too. Search for bumper removal by TwinsPoppa. Very nice, picture intense, how to.

thanks for your help and the links, i had hoped that the fan removal would be fairly straight forward, as it seems however, without removing the front bumper you cant even see the mounting screws.

however before i get to involved i think i,ll take the advice and get the gas levels checked,
and see what happens, hopefully thats all it is

thanks again to all that commented, its appreciated

I am also going through this same problem, my X was taking about 15 mins to start cooling, I had read a post on here that said the compressor is worn and takes a while to come on stroke (variable compressor not switched on and off).

So I buy a new compressor from the states and have a mate do the install and gas. He did this and noticed the Auxiliary fan was not turning, he said this will cause high pressures and heat in the system which is probably why the compressor was on it's way out.

The AC works straight away now but heats up at the lights because the fan isn't running. I had checked quite a few times to see if the fan was going but it never spun.

So I got a new fan from the states, and installed that (petrol fan just changed the motors over as the shroud has a fill in piece where the intercooler is). It still was not spinning, but I noticed today just after starting it it spins but only for about 10 secs, I checked it a few times today and noticed after a drive and re started it itwould spin a high speed but then slow down to a stop.

Don't know if this helps you...

So at the moment I'm looking at the AUC sensor, (little black box connected into the harness). Does anybody know about these??

I also have a this code coming up
41F0 Electric Ventilator - Short Circuit to B+

OK just found this
"That sensor box thing on the top of the fan shroud is for the automatic recirculation"
so that is useless...

When your "mate" installed the compressor and added gas, did he properly evacuate the system, then weigh the freon installed?

I have yet to mess with the A/C on the X, but on one of my other cars, if it does not get fed the precise amount of freon, it will display the same symptoms you are describing. Too much freon, and the system shuts down while in traffic when it's really hot out. As soon as you get moving, it's fine. Nothing to do with the fan....underhood heat raises freon pressure to an unacceptable level, (even if the engine is not hot enough to decide it needs the fan turned on). There is a high pressure switch that shuts the compressor off. Same thing if the pressure is too low. And it is virtually impossible to get this car right with just a set of compound gauges...you must have a scale. You can use a seperate scale, or most of the advanced freon machines have one built in. The older and also less sophisticated machines just use pressure...not good enough.

Yup +1. Good description Skyline

Also if you search. We have members on here that noticed the fan not spin. Then while evacuating the entire system, and filling in freon, the fan kicked on, and increased speed as the pressure reached proper levels.

BTW...this is what my friend's shop uses to refill A/C:

EEAC325B, Service Center, A/C, KOOL KARE™ Plus, R134a

This thing is almost totally automated and computerized. A tech with NO A/C experience could fill a system on the fussiest of cars without screwing it up.

You hook it up, then program in the type of car you just hooked up. It will first completely evacuate the system, and test that it holds a vacuum. Then it tells you to start the car and it will automatically fill the system with exactly the correct amount of freon, (by weight). It adds the correct amount of compressor oil at the same time. It also adds a shot of UV dye, just in case a leak develops. It will pause in between steps and tell you what it wants you to do. Perfect charge every time....pretty awesome. But given the price of this machine, you would expect that.

I have two cars that could care less how much freon they have; charge it until it blows cold, and you're set ('96 Jeep Grand Cherokee and '04 4Runner). My Infiniti is incredibly picky; it takes a good machine to get it working right. Then there's the X5...which has yet to need attention; so I don't know.

Based on what I keep reading on the forums, the X is also very picky. It takes very little freon, and it needs to be pretty close on the money to function properly.

Yes it was done properly, evacuated and weighed. It doesn't matter if the engine is hot or cold, fan must run if AC is on or the pressures will rise and cause boiling of the gas when the car is not moving.
Remember I have an error (electric fan)

hmmmm, hard to know what to do, i still think the gas level needs checking first, then maybe the fan.

why couldnt it be a simple 12v supplied = fan on no 12v fan off, with this pulse thing it makes it all that much harder to fault find, or am i missing something

yeah I have run out of places to look. I was going to put an oscilloscope on the fan today but didn't get time, will have to be next week...

If you have access to GT1, it can turn on fan for testing. Otherwise, you need something applied to that pulse wire. I don't remember what though.

ok called in on the a/c repair guy and he says i have to take it to an auto electrician first as he cant diagnosis a faulty fan.he said that if when running the a/c is cold then he doesnt believe its low on gas ( and it does)

seems i may have two faults
1/ that, as others have experienced the a/c is slow comming on, often taking up to 10 minutes, and especially if the car has been sitting for a couple of days or its been sittin in the heat
2/ the cooling fan in front of the radiator is not working, causeing the a/c to loose efficiency when the car is stationary.
ive checked and there is 12 volts to the fan however i cant tell if the fan motor is dead or its not getting pulsed to switch on so.........

i had a look on ebay and came across this (251186015362) is this what i need to access my cars software?? using this can i turn on the fan or at least determine if its ok??

and is this what people use to reset and turn on/off different functions

all help is greatly appreciated

ive stayed away from messing with my cars functionalities and reprogramming although have researched and followed many threads on the topic.

i think its time i bit the bullet and got into it

oh my car is a 2005 x5 3.0d sport

Can you post a link? Thanks.

That unit from eBay is like the car soft one I have. All it can do is tell you there is a fault with the fan and a small amount of set coding.
This is more like what you need
http://bit.ly/QAEvU0
BMW GT1 DIS v57 SSS V41 V41 FIT ALL COMPUTER OPS TIS
Or look up icom BMW on eBay.

kool thanks

just got my car back from the mechanic 150,000 k service and oil service plus they couldn't conclusively diagnose the fan so they took it to auto electrician $700 geeeesss

anyway apparently the fan controller on the fan motor is dead, and BMW want wait for it

$1400.00 for a replacement PLUS labour to fit, thay have to be joking

looks like i will be searching out a fan and doing the job myself.

somebody recently posted a how to so thanks guys its going to come in many thanks

update, just ordered a fan locally from a guy who imports from Germany just under $500, so just a little more that a third of what BMW want

Yeah I got quoted $1400 as well. Imported one from the US, the fan motor is the same at the petrol one it's just the shroud that is different.
Hope that fixes yours, it didn't fix mine...

Wait so did he actually try and evacuate the system and refill it?

no he wouldn't touch the gas, he said that if the thing blows cold when running then in his opinion the gas level was ok, he sent me off to sort out the fan first.

so i had my mechanic test the fan ( something i learnt here , thanks) and the software said it was inconclusive, so the mechanic sent it to an auto electrician, who tested the fan and concluded that the controller is dead.

so ive ordered a new fan, and will fit it myself ( again thanks to this site) and see what happens.

i saw on Bimmerfest someone claimed that if the pusher fan was faulty then that can also cause the a/c to be slow starting, i assume that the a/c controller may pulse the fan, and if it doesn't get the response it expects then doesn't allow the a/c to kick in till other parameters are met, just guessing here as i simply don't know.

however once the fan is replaced then i can assess the thing further.

Checked the signal coming from the black wire on the fan with an oscilloscope and found it very eratic. It is showing a square wave PWM signal but it was between 3-5volts while the fan was turning and when it was stoped it was all over the place .44V to 2V.

I also have another spare new fan here that I plugged in and it did the same thing, stops after about 10secs.

Does anybody know where the signal comes from? or have and schematics.

I am pretty sure it is directly related to the pressure switch coming from the AC system. Not sure where it comes from, but you are not the first to report the same findings. Please go to another AC shop and get them to evacuate and refill the system. It should not cost much, but it will, at least make sure that is not the issue.

That voltage level seems ok. There is a power transistor in the fan box that is driven by this low voltage signal. There should be also a 12V and GND wire (bigger wires) that have a potential of 12V between them while the fan is running.
Check to see if there is still 12V between the 2 big wires when the fan stops. If not, either the ECU decided to turn off the fan, or there is a bad contact somewhere. If there is still 12V but no PWM signal, I would check the signal wire to make sure everything is normal.

ok my replacement fan arrived last night and i plugged it in while sitting on top of the motor cover, turned the a/c on and away it went, so next challenge get it fitted.

Yarno when fitting yours did you have to remove the intercooler?? i cant see the two mounting bolts, it seems that the lower part of the fan assay. disappears behind the intercooler, can you confirm???

so after work today im getting stuck into it, ive printed out twin poppas (thank you) instructions and am ready to roll ( i hope)


on my car the two thick wires have constant 12v even with the car off, with the car off i placed the new fan on to of the motor and connected it to the loom and just for an instant the fan new fan kicked on, then off.

turned the car on and the a/c on and away it went.

once i have the new fan in i plan to run it for a few days to see the results, if the a/c is still slow coming on then i will take it to get regassed

No , intercooler stays in. Just remove the plastic bumper and then the metal bumper. Fan will come out.

thanks, im on to it this afternoon, i get home early on fridays so head down tail up and in to it

ok its in, took me 2 hours and it works perfectly, now i just need a couple of days to see if the slow start is cured.

i bought an after market fan and i could only get one to suit the petrol engine cars, the seller said most people just take the fan and controller and fit it to the old shroud.

the turbo diesels have the intercooler below the radiator and this protrudes in to the space there the fan sits on petrol engine cars.

however my original parts felt brittle so i decided to modify the new shroud to suit my application, and it worked well, i also took the opportunity to blow compressed air through the radiator and intercooler to clear out any debris.

didn't loose a single fastener, although i did manage to break one clip on each side where the bumper wraps around to the wheel opening

oh one other thing, on diesels you have to remove the steel bumper as well otherwise the fan will not come out

so many thanks to those who do write up on these sort of things its much appreciated, i wish i had the patience to take the time and do the same

So doess the fan stay on?

the fan does stay on while the a/c is running, obviously i cant tell if this is the case when the car is moving.

only bummer is that it hasn't fixed the slow coming on problem.

so now as i have the electrical working i guess its time to take it back to the a/c repair shop to get gas levels checked, however from reading around i,m of the opinion some one is going to be replacing the compressor

Ok I have just been to the Auto electrician that does a lot of euro cars. I told him what was happening and what I had done (replaced Compressor and fan). He says mmm I think you have the wrong fan. I told him then that yes it was a fan from a petrol model. He said that that would 100% be the problem.

So now I am confused as to what to do, Bigwave's seem to work with the petrol fan, but mine definitely does not.

I have looked at the schematics on here
Engine cooling - BMW WDS
Electric fan - BMW WDS

And compared them, the look a little different.... not to sure.

What to do, another fan is $521 from Schmiedmann

Are you sure yours works Bigwave? No warming up when sitting at the lights?

Hi Yarno.

mine works fine with the petrol engine fan, i was led to believe that they are all the same, the only difference is in the diesel cars shroud, its trimmed down at the bottom to accommodate the intercooler, it sticks out past the a/c condenser (??)

my fan works when the a/c is working, however my a/c is still taking about 10 minutes to kick in when the car is first started or if its been sitting all day, however if im using the car running around then the a/c works immediately, and when working is super cold.

i reasonably sure i had two problems, 1/ that the fan had died and 2/ that the thing is slow on,

i also have to add what while i don't know if my original cooling fan is the original BMW fan from manufacture, the replacement fan is different in that the controller on the original fan was part of the fan motor whereas the replacement after market fan has a separate controller, the 3 wires go to the separate controller and then the 2 heavy wires continue on to the motor.

the separate controller also has a dirty great heat sink on it, and the heat sink is positioned in the upper rh corner of the shroud ( looking from the drivers position lhs if standing in front of the car) and facing towards the front of the car

this was another reason i chose to modify the new shroud to fit , as it was not possible to easily mount this separate controller within the original shroud.

i really cant see how your fan could be at fault, and from all i have read the fans are all the same its just the shroud for the diesels that is model specific

so now i have to sort out only why the a/c is slow coming on

Fan needs to be on when the compressor is on or the pressure on the high side will build up so much that the high pressure switch will turn the system off. When you are driving and not stopped there is enough air flow that the fan isn't really needed to cool the refrigerant in the condenser.

yep, correct.

OK got my new fan from Schmiedmann, ended up about $540USD delivered. Plugged it in and away it went. Installed it this morning and it is all working fine. Thanks everybody for the help.

Well for me, the link file were unable to open, but as a guy who like to figure out stuff
I ended up removing the two screws that held the aux fan in the bottom, and also pulling
the entire bumper half way down. But unfortunately I still Not able to see how the aux
fan will come out (It is from the back or coming out from the front bumper??

Otherwise I have similar symptom as described above like Not having enough A/C
when stopping/or car blowing hot air inside. And I went and bought a new fan on ebay.
I set the new aux fan on top of the engine, unplugged the old one while still on the car, plugging the new one in the same plug, now I went to start the car and put the A/C on

After 3second, Boommmmmmm the new Auxiliary fan kicks in while sitting on top of the engine cover. So, this was a good sign showing me that the old culprit wasn't working.
and I plugged the old one back, but the culprit wasn't spinning at all.

Now I just wanted to ensure where the aux fan comes out. front? or back?
(2001 BMW X5 4.4i)

The pulse governs the speed of the fan. The faster the pulse the longer the fan is engaged so it will spin faster whereas the slower the pulse the shorter the fan is engaged so it will spin slower. This eliminate the use of resistor packs and everything is controlled by the DME.

If the fan is not working the computer will know that it is not working and store a code for a fan failure, but that type of failure will not trigger a CEL or SES or MIL. Get the X scan to see if there is a problem with the fan instead of throwing parts at it.

If the fan is in front of the bumper it comes out from the front. But you must also remove the actual metal bumper that the bumper cover covers. Why? Because there are two plastic shrouds that are located in front of the fan and the only way to remove them is with the actual metal bumper off. The shrouds are held in place with 2 plastic rivets on each shroud.

Aux fan removal
 

Thinks upallnight:thumbup: for the info
However I got through half way there, but I hate thinking that I had also
to remove the metal bumper in the back of the plastic cover. Unfortunately I was unable to finish the job yesterday because of this. So now I know what
to look for and I will get through it eventually.

01 x5 4.4i

Pulse signal for the fan comes from the DME. DME only provide a signal when the ac switch is activated and the system is running. If the system is not running due to low refrigerant, the DME does not pulse the fan. Not sure if the DME detects a bad fan if it will turn on the compressor for the ac system to work.

Yarno! Happy that you've got your aux fan working now, but do you remember
how and where you got the auxiliary fan out? Did you slide it out from the front
after entire bumper was removed, or it came out from the back.

Thanks for any input you may have in regards...

(01 X5 4.4i)

Fan defiantly comes out the front.

http://www.xoutpost.com/articles/x5/...r-removal.html

http://www.xoutpost.com/bmw-sav-foru...ditioning.html

Once you remove the two bolts that secure the fan housing to the radiator frame, you can pull the fan down.

Very Appreciated Upallnight!!! What's a good confidence you give me...
I'll keep you guys posted on the outcome and possibly taking a few pics.

Auxiliary fan fixed!!! (01 X5 4.4i)
 

Thanks to all your helps outhere specially Upallnight!!!:thumbup:
I just wanted to make an update on the A/C Not working due to
dead auxiliary fan, and keep pushing Hot air inside the cabin.

Unfortunately I did Not have pictures coz I was trying to get done as quickly
Well, I don't know for other year/models, but after several attempts to get
the Old fan out of the car, I discovered that the auxiliary fan comes out from
under the bumper, meaning sliding under the car. But it is much easier to have someone with you like I did, otherwise the bumper just needed to lay down
a little bit, :damn:not completely remove. Once you locate all the screws and
remove them, the bumper just need to slightly lay down so you can remove
the two sides plastic peaces one on each side that holds the air around and
remove the two screws that support the aux fan, you're good to go.

I just did the same reverse procedure by sliding the new auxiliary fan under the front bumper about 5 minutes, the new fan already installed.
I quickly connected the aux fan and start the car, put my A/C on to see
the effect and Booommmmm Aux fan kicks in, and now I immediately noticed
that my cabin filled with cold air like never before and say bye bye:nanana:to hot summer time coming.
(2001 X5 4.4i)

Updated!!!
 

Thanks to all your helps outhere specially Upallnight!!!:thumbup:
I just wanted to make an update on the A/C Not working due to
dead auxiliary fan, and keep pushing Hot air inside the cabin.

Unfortunately I did Not have pictures coz I was trying to get done as quickly
Well, I don't know for other year/models, but after several attempts to get
the Old fan out of the car, I discovered that the auxiliary fan comes out from
under the bumper, meaning sliding under the car. But it is much easier to have someone with you like I did, otherwise the bumper just needed to lay down
a little bit, :damn:not completely remove. Once you locate all the screws and
remove them, the bumper just need to slightly lay down so you can remove
the two sides plastic peaces one on each side that holds the air around and
remove the two screws that support the aux fan, you're good to go.

I just did the same reverse procedure by sliding the new auxiliary fan under the front bumper about 5 minutes, the new fan already installed.
I quickly connected the aux fan and start the car, put my A/C on to see
the effect and Booommmmm Aux fan kicks in, and now I immediately noticed
that my cabin filled with cold air like never before and say bye bye:nanana:to hot summer time coming.

Congrats. You'll enjoy that cool air come this summer.

Your description sounds just like the Calsonic variable displacement control valve problem outlined by g300d. http://www.xoutpost.com/bmw-sav-foru...-ac-delay.html
http://www.google.com.au/url?sa=t&rc...45645796,d.aGc

yeah it does, ive just been putting up with it , and now as we move into winter ( australia)
its not such an issue,

however one thing i have noted is that the a/c will kick in sooner the cooler the weather is,

its on my short list for repairs over the winter, i originally took it to an a/c repair shop but they wouldn't look at it till the electric fan was working, so i replaced the fan and haven't had time to get them on to it again

I have the same problem, and I've noticed the same thing, but I think it's because in summer as soon as I switch on the X5 I want A/C, and after a while it kicks in.
So the solution would be 1) replace the compressor ,2) replace the control valve, or 3) modify the control valve so that its on as soon as the compressor engages, so locked in position, with some relief mechanism if necessary. Modifying seems the best choice, because replacing the compressor, it could just happen again at some stage. Just got to find someone who understands what needs to be done, and can do it...