2006 BMW X5 3.0I AC Condenser and Aux Fan Cause Overheating
 

Hello,

I saw a couple of your posts and I am hoping you can answer my question. I have a 2006 bmw x5 3.0i. It over heated the other day while I was stopped with the ac on. The AC was not blowing cold at this time. It takes 10+ minutes sometimes to kick on. I let it cool down, turned the ac off and drive it home with no problems. When I got home I tried the ac again and noticed the condenser was not engaging nor was the aux fan. I let it run at idle for already 10 munchies with the ac selected and no changes. The air was still warm, the condenser wasn't on, aux fan wasn't spinning and it was at normal running temperature. I took it to the local shop and they told me that the aux fan needs to be replaced. They said that the condenser won't kick in if the fan is bad and they have no way to test the condenser. I just want to make sure the condenser didn't burn up and waste $800 to fix a fan and still have no ac. Is it true that if the fan is bad it will prevent the condenser from kicking on and could I have burned the condenser up by trying to run the ac with the aux fan not working? Thank you in advance for any help you can give!

The first part is true. I'm not sure about you burning up your condenser however.

Ok thank you for your response! I just want to know
before I spend all of that money to fix the fan.

^You can fix it for much cheaper than that if you do the work yourself. If you are unable, or it's not worth it to you though, I understand that as well. I find that the older I get the more I'd rather someone else turn the wrenches... unfortunately that is seldom an option for me with how expensive labor is.

I was under the impression, and someone else who has experienced this can chime in (I think Trader had, or has this issue with his fan), that the compressor will still function provided the charge is where it is supposed to be. The only reason your compressor would not engage is if the pressure switch is tripped or the clutch failed I believe.

So the condenser should still function even though the fan is bad?

I just bought this car. I put maybe 50 miles on it and already sunk $2000 into it on top of the purchase price between tie rod ends, tires, alignment, oxygen sensors, oil change, brakes, detailing etc. I don't know if I could've broke the condenser by running the ac with a bad aux fan causing Overheating. Thank you everyone for your any advice

First off lets get the terminology correct. It's the COMPRESSOR that turns on Not the Condenser. Only way that you can burn up a compressor if you ran it low on oil and it suffered what is know in the industry as the Black Death.

There's one member on this board that will tell you that he still get ac even with a fan fault. It depends on how the fan failed. You can test to see if 12 volt DC is still available at the fan connector. It should be present whether the key is on or off. No 12 volts will indicates that the fuse has blown. Only reason why that 50 amp fuse will blow is if the aux fan shorted out. If this is the case you need a new aux fan.

Here's a post from another forum member with the same problem and his fix:

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

Oh, I thought you meant the compressor. The condenser is basically just a radiator for your AC system. It does some other stuff, but is just a mechanical device. Running without an auxiliary fan will not damage the condenser.

Oh, and spending $2000 after purchase price on a used BMW is pretty standard fare. Only way to avoid that is to pay top dollar to an enthusiast who has already done the work that 99% of used BMW's need. Most owners don't do the maintenance they are supposed to on time, or decide to live with check engine lights, clunking suspensions, etc until they trade the vehicle in or sell it to pass on the problems to the next guy. Sad, but true.

There is power to the fan but the fan does not come on. That's what I was told by the shop. They said once I replace the fan the compressor should function normally. There is no way for them to test the compressor. Thank you for classifying the terminology!

BTW I am referring to the ac compressor not condenser

Crystalworks, I am referring to the compressor. Also I am guilty of diving my last 3 series with the ses light on for a while before I traded it in to lol

Compressor is the right terminology, the op is using condenser instead of compressor. If a shop is telling him that his condenser doesn't turn on because the aux fan is bad, I would run not walk away from that shop. Most likely because the owner is new to BMW he probably confused condenser for compressor.

Wow $2000 after buying a BMW???? Even enthusiast don't always keep up their BM Trouble U. I use to belong to the local BM Trouble U club and many members once the warranty was over they stop bringing their cars in for work and just drive them until they buy a new car.

Lol I want to make sure it's safe for my family and don't want to break down. Will the compressor not come on if the fan is bad? The belt spins the pulley but the clutch does not engage. Could this be because of the fan being bad?

YES!

I all ready said this. If the fan is bad the compressor will not come on unless you modify something.

Ok great. Thank you for your help!

Yeah, I didn't mean ALL enthusiasts maintain their BMW perfectly... but the way to get a good one is to buy from one of the enthusiasts who do. :D LOL or buy a really good aftermarket warranty... which usually still costs $2k - $3k based on the quotes I was given for my wife's e83 mtech X3.

OP, I'm not sure why your compressor isn't turning on. A bad aux fan alone will not cause that I don't think, unless the pressure is building up and tripping the pressure switch. Even if that were happening, you would still get cold air while you were driving at highway speed when air is moving over the condenser.

That is what is confusing. The shop told me the compressor will not engage if the fan is bad. Some of the posts that I've read said that is true and some say it is not true. Member B-M-W says that is correct. I am hoping he is right because I gave the shop the go ahead to fix the fan.

Don't hope that I am right.

Your vehicle is programmed to disable particular items when a fault occurs and this is one of them.

What you should be doing is taking the fan apart yourself. This is a very easy DIY.

Thank you B-M-W!

I wish I knew how to do it. I read some other posts that say the front bumper has to be removed.

Good to know. I guess all the modules are tied together and communicating faults and the like. I am used to diagnosing older BMW's I must admit... :D

OP, perhaps your shop diagnosed your problems with software which told them the compressor was not engaging due to a failed aux fan. That would make sense.

I'm not sure how they came up with that conclusion. When I asked them if they can test the compressor they said they couldn't and that the fan was the culprit. It didn't make sense to me either but I'm used to the older systems as well.

Well lets hope the shop just doesn't throw a fan on the vehicle because its not coming on.

Here's a post on fan fault:

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

And why the AC didn't work.

Here's another post on a bad fan preventing the compressor from turning on:

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

Wow! That post describes and explains my problem perfectly! Thank you upallnight!

We ran for 3 weeks without the AUX fan but had AC while driving. When we bought the CPO X5 we had 11 service visits in the first month. It would seem the CPO pre-sale inspection was never performed. The last thing I went in with was the suspension clunk. Told it needed $1600 - $2000 worth of steering/suspension bushes. The SA was a nice guy who had just come over from a Ford dealership. I explained to him that it might be better for his boss and the dealership to "eat" the repair bill as I was sure the legal fees they would pay would come to more. In the end they agreed as their tech had "missed" the suspension/steering problems during the CPO inspection that never took place.
The SA went back to Ford the next week because he could not cope with so many disgruntled customers!
I might add that this was the dealership that provided Toyota loaners because "they never break down".

I just talked to the mechanic again and he said there is power going to the fan and it is not kicking on. He guaranteed that replacing the Aux fan will fix the Overheating and ac problem. I will post the outcome on Monday evening after I pick it up.

That makes sense. Before the overheat and no more ac. It sometimes took a long time of driving for the ac to kick on. It never kicked on right away. It was at least a 5 to 10 minute drive most of the time but when it finally kicked on it was immediately cold. On the day it overheated I just picked it up from the mechanic who cleared an o2 sensor code, changed the tie rod ends and did an alignment. After picking it up I drove it about 20 minutes and the ac was not coming on. I left it on in hopes of it finally turning on. On my way home I stopped to grab some dinner for the kiddos. While I was at a stop for a couple of minutes with the ac button on (note still no cold air) I noticed it was Overheating. The needle was in the red and it warned me that the coolant was hot. With that said I am thinking even though there was no cold air coming from the vents the compressor was still functioning which caused the Overheating.

If your mechanic is not using BMW specific scanners to troubleshoot the BM Trouble U I would look for another mechanic.

He says he is familiar with the bmw so we will see. I will post the outcome tomorrow

I agree.

Though on another note, I've never understood why people refer to BMW's as BM Trouble U's. I've had over 10 and not had any unreasonable failures. Three of my BMW fleet has over 150,000 miles... and one has just under 400,000 miles. All are still very good cars. :dunno:

I understand they are not on the level of Acura, Toyota, and Honda "change the oil and forget it" type of maintenance, but they drive/handle about 4 classes above those cars as well.

My FORD Ranger was known as Fix Or Repair Daily

Lotus is an Acronym for Lots Of Trouble Usually Serious.

Ah, I've heard the Lotus one as well. That particular Ford one is new to me, I had heard a much more negative version. LOL. So it's more a "term of endearment" than an actual derogatory label. Gotcha. :thumbup:

It's been my experience that BMW's suffer the same kind of failures as most marques, and usually dependent on how well the vehicle was maintained by the owners (as with any brand car).

OK that's a really good point you make. I will mention the mechanical fan as well to them and post the outcome later today. Thank you for your advice!

I've seen all of those failures on other vehicles, minus the FSU resistor. At the shop we routinely saw failed regulators on just about everything... though admittedly more prevalent on BMW's. I've had 3 regulators fail on me as well throughout the BMW lineup and age range... luckily no broken glass though.

The valve stem seal issue I agree with completely... but they were redesigned so BMW at least updated the parts to not fail again. Too bad they won't repair the failures or at least good will some of the labor.

I also agree with trader OP... get that aux fan replaced and go from there. Maybe have them evac and refill the A/C system (after verifying the fix did the job) while they are there as it is probably due anyway.

OK I'll ask them if that is also due to be done. This particular shop has done all of the work on this car for years. They'd probably know if it's due. Thank you for the advice

Update: while the mechanic was changing the fan the condenser was damaged. It had gotten a hole in it. Anyone attempting to change the fan be conscious of how tight the fan fits. I'll post more when I get the car back with an update

I changed the fan on my X without damaging the condenser. Appears you mechanic don't know what he is doing. Hopefully when he change the condenser he will put back in the right amount of PAG oil. Any time a system is opened it is also a requirement to replace the drier/receiver.

I hope he knows that. I'll ask them. If you don't replace the drier/receiver what could happen?

The receiver/drier is to trap any water moisture in the system. If you have moisture in the system, the moisture will freeze and it may plug up the orifice tube. A clogged orifice tube will not allow refrigerant to pass through so in effect you won't have ac until the ice within the system melts.

That is a great bit of info. Thank you. I am going to call first thing in the morning

In this case the orifice tube is the expansion valve correct?

I am very surprised the condenser was damaged removing or installing a new aux fan. I'd be concerned about the quality of care my X was receiving. :dunno:

I am going to have to make a call tomorrow and see if they are going to replace the drier/receiver. If they say they aren't going to, what do I do? Is it mandatory that it be done? Meaning are they obligated to replace it being the condenser got punctured in the process, or can they say I have to pay for that if I want it done?

If he doesn't replace the receiver/drier, have him vacuum the system for an extra 30 minutes. The longer he vacuum the system the more moisture is boil away since water boil at a lower point when it is in a vacuum.

I contacted them and they planned on replacing it

Thank you for the advice

Congrats. Good step in the right direction. We all hope everything works out fine.

Now we have to get you into DIY more...

Thank you again everybody for all of your help!

I don't want to talk to soon but I picked it up and all seems well. They replaced the aux fan, condenser and drier. I drove it about 40 miles after picking it up and no overheat, no check engine light and ice cold air! Thank you everyone for all of your suggestions and advice! You are absolutely right I definitely need to get into more diy. It's expensive to fix these cars but they truly are a pleasure to drive. This is my 3rd bmw but first x5 and I love to drive everyone of them!

Update: I drove it for a little while yesterday and the service engine soon light came on. I called the mechanic and it's set to go in on Tuesday. I got in it today and started it up to run down the street and the service engine soon light wasn't on anymore. Is it normal for the light to go on then turn off? If so what can cause that?

Get yourself a scanner and do some of these work yourself or you are going to regret the day you brought that BM Trouble U.

A misfire will turn on the light after x number of misfires had occurred in the cylinder. Turning off the engine just reset the counter for the misfire and the light will go off until the number of misfires has ocurred again.

If you are an Android person and didn't drink the Apple Cider, you can down load a free app Torque.

Or you can purchase Carly BMW which I've used with good results. It's $55 I think but was worth it for me. Torque is a good option as well.

I am an android user. The last time the light came on there was a code for misfire low fuel (I believe that's what it said) but it has never ran with low fuel. Could that mean something? Also what would cause a misfire if that's what it is? I'll look into Carly BMW. THANK YOU!

Any time the computer see a variation in speed after a cylinder fires, it count that as a misfire. The computer keeps track of all the misfires in each cylinder and when the misfires exceed a certain limit it throws up an SES light.

A misfire could be from a bad spark plug to low compression in a cylinder to a burnt valve, to a clogged injector or a dead injector.

Thank you upallnight. How can I narrow the problem down?

I think the mechanic mentioned one of the codes meant there was a compression issue. This was about 2 weeks ago. He reset the light and said it was a misfire probably due to running with low fuel. I know it never ran with low fuel though. There is no lack of power and I've never heard a misfire.

You are thinking of a typical old misfire situation when the cylinder is actually dead. In these computer controlled engine, the computer is able to detect the slightest variation in the power from each cylinder. The cylinder may not be dead, but it is weaker than the rest of the cylinders. The computer consider this a misfire.

Have you run an ac pressure check ? If there is insufficient coolant pressure than changing the aux fan won't fix anything. If the compressor is damaged changing the fan won't fix it. Is this shop specialized in AC repair? I changed out my pusher fan for less than 200 drove from FL to ME 4 months ago and everything was perfect. However, because the fan wasn't working properly the temp in the system rose and released refrigerant. My shop evap and filled the system and then I changed the fan.
DON"T spend a dime until you know for sure if your compressor is good.