Air Con not cold - Advise required
 

Guy's i've only had my X5 a week and with the weather we have had today noticed the AC wasn't cold. Decided I would take the X5 to have the AC re gassed. the job is all computer driven and no room for engineer error however the engineer I has was very informative and knew what he was doing.

Anyway after 30 minutes the re-gassing was completed but unfortunately the temp did not go down, on the up side they did not charge me as this is their policy if they can't bring the temperature down.

The result are that I don't have a leak, the car was holding 270g gas and 2ml of oil before th regass and the machine inserted 440g gas and 12ml of oil. Unusually the reading given was that the low pressure reading was high at 7 bar and the high pressure reading low at 6 bar.

The AC control in the car operates fine, it blows hot or ambient, controls work as far as I can see. I can't say I've seen the AUX fan operate, now from reading what I can find on this forum I've narrowed down the issue to either the final stage relay, the compressor it's self or the Aux fan. What I'm not in a position to do it purchase these items from BMW to find some of the parts are not needed.

Has anyone any ideas on how the diagnose this issue, ie a step by step guide on what I should be doing to identify what and where to look, I don't even know where to locate the compressor. are there drawings on the internet?


The car is a 2004 4.4i with 62k miles.

I've checked to day, when I press the AC button the AUX fan does not spin, the revs do not drop.

I do have one question though, which is the power to the fan out of these two pictures to guage a voltage from?
http://lh5.ggpht.com/_eDzc-YGUk7o/S8...2/IMG_0450.jpg

or
http://lh4.ggpht.com/_eDzc-YGUk7o/S8...2/IMG_0451.jpg

Lastly should there be a cable connected into the other side of the connector seen in the first picture?There are 4 cables in one end and I can feel the other end is a plug type but no cable visable. Could this be my problem?

Lastly where is the AC compressor if I'm facing the engine? Should I be able to see it and the belts?

you may want to pickup a Bently which will give you a better idea of what goes where. You also can try to use the parts diagrams on realoem.com to get the same idea. Sorry could not be of more help.

Anyone able to help with my questions?

Answer these two questions . . . Is the compressor clutch engaging when your A/C button is pushed? Does the vehicle blow cold air near the end of a short highway trip?

If you compressor clutch is not engaging, the DME will not allow the AUX fan to run. Also, if the AUX fan is out the DME will not allow the compressor clutch to engage. Kind of a catch 22 for diagnosis but easy to figure out.

Answer the above 2 questions and we'll move on to the next step in your diagnosis.

check your fuses?

Cheers guys, the first thing I checked was the fuses and there all ok.

Is the compressor clutch engaging when your A/C button is pushed? Does the vehicle blow cold air near the end of a short highway trip?
I guess not, however I don't know where in the enigne bay the AC compressor is located to check, the revs don't drop when the AC button is pressed. The air does not go cold when driving at low or high speed.


Would an independent BMW garage be able to indetify which item is at fault?
Could it be the FSR, the temp controls work fine as does te auto button.

The compressor on mine (3.0L) is located on the bottom left side on the front of the engine as you are looking from in front of the car. It will have two metal pipes that convert to rubber hoses connected to it in near vicinity to each other and of course a pulley on the front connected to a belt. The pulley will continuously spin while engine is on but the part inside of the pulley will only spin while A/C button is pushed.

It doesn't sound like it is engaging to me, need to find out if voltage is being supplied to the compressor clutch. If voltage is being supplied, then bad compressor clutch. If no voltage being supplied, probably bad AUX fan. Either one can be $expensive$! The fact that you don't experience a kick-down of engine rpm makes me think it might be AUX fan as you would still hear/feel a kick-down if compressor clutch is bad because that function is handled seperately from the compressor.

My A/C compressor clutch went out before on me and was looking at $500ish for a new compressor just because of that little crappy clutch on the end. I just replaced the clutch only with an aftermarket generic that seemed to be same dimensions and haven't looked back since. $39 by the way was my total cost for that fix.

Could you send me a link or contact for the clutch repair? Also how easy is it to get the AC compressor out? Assuming it's accessed from under the car.

When the shop recharged it did they vacuum out the existing contents? In climates where vehicles see hot-cold-hot-cold (like in Northern Indiana) oxygen and water can form in the AC system. Then when people buy the bottles of R-134 from Walmart and charge their systems nothing happens, and the compressor kicks in an out or not on at all. Adding a charge may not fix your problem. A full vacuum needs to be applied (this is when they do a leak test) then a full charge. Just got done doing this on my F-150 and will do the same on the X5.

is the temperature the same coming out of all the vents? mine wasn't and fixing the water valve fixed the issue. indy said water valves are common replacements for him.

http://www.xoutpost.com/bmw-sav-foru...failure-6.html

http://www.xoutpost.com/bmw-sav-foru...pressor+clutch

The first link is the link I followed to help me with my repair. The second link is my post while doing my repair. These were both on 3.0's I believe.
Getting the AC compressor out is standard for a BMW. First you have to remove everything else under the hood then you can get it out.:D I tried to make the swap with the compressor still on the vehicle but did not have enough room. Ended up having to remove it which included cracking open the system and then having to reseal it, vacuum it, leak test it and refill it.

Make sure your diagnosis is correct before you start replacing stuff or you could spend more than what the correct repair would cost. Do a several searches on "ac problems", "compressor coil", etc. and do some reading. That is partially how I figured out my problem. I was all set to order a $450 AUX fan when I was able to properly diagnose that the AUX fan was not the problem.

Repoman, thanks for your advise.

Just one thing I have noticed today, car is ideling, when I press the AC button the rev go up ever so slightly, press the AC button again to turn it off and the rev drop to normal. Would this suggest the AC compressor is coming on?

No, this does not mean that the AC compressor is coming on. What it does mean is that kick-down is working properly which is seperate from compressor function. Mine was also kicking-down everytime I pressed the AC button but no compressor lockup. It will still kick-down even if compressor is not working properly.

The only way to verify is to put your eyes on it. There's no other way I can tell you verify it and can't really help any further if you can't verify it.

Find the compressor, push the AC button and look at the part in the center of the compressor pulley to see if it is spinning or just sitting still. There's no other way to tell!

How do I see the clutch?
 

Hey all,

I am having the mysterious A/C slash Aux fan problem too. I am trying to see if the compressor clutch is engaging but I don't have an angle on it. I can see the top of the compressor but not the center of the pulley. I have a 2003 3.0i. AM I missing something here? Do I need to get under the car or use a mirror on a stick or something? My indy mechanic (who does a fair amount of BMW work) says the pressures on the compressor are really low (he says basically the compressor is not compressing), but it seems to me that this would be true if the clutch was not engaging, and I am not sure he knew to check for that. He believes my aux fan is shot too, so I don't want to replace the compressor ($1200 from dealer) if the problem is the aux fan anyway. Any hints on this?

You should be able to get your hand in to feel if the pully is free, Take off the air duct and air box if required.

My AC issue was resolved not by replacing anything but in fact plugging in the power cable to the AUX fan which had not been plugged back in by BMW!! when I had the waterpump replaced ealrier this year, I was going to take my X5 to a car electrical specialist as these faults tend to be more electrical than actual AC releated.

Yikes! Is that safe to do while the engine is running? (putting my hand in?) When I get home I will try to look at the box and duct you are talking about and get them off.

Would it be easier just to get under the car, I wonder?

No, the engine will be off, once you have your hand in you should be able to manually move the compressor pulley, This will only tell you if the compressor is seized or not. There is plenty of reading on this forum for the 3.0i engines and AC issues and fixes. Also allot easier to get your hands in to check things compared to the 4.4i lump, might be worth unplugging the AUX fan power lead, cleaning and reseating. It might be this, if not check it has 12v going to the AUX lead.

Were can I find the AUX fan power lead on a 06' 3.0 ?

picture one in this post shows the socket. If looking into the engine bay it on the top right of the innner fan. The picture shows the cable missing, unplug the cable and test the voltage when the AC is turned on and off from the temp controller in the dash.

BMW X5 3.0 Air Conditioning issues
 

Ok guys, I have a slightly different problem with my A/C. When I start the car in a hot day and the climate control is set to AUTO, the fan blows at the highest setting, as it should, but no cold air comes out while idling. The cold air comes out five minutes into driving, specifically when the engine/car speed picks up. In the highway, the air feels really cold as it should. I checked the refrigerant levels, and it is normal/to almost high pressure levels. While measuring the refrigerant pressure, you can definitely see when the compressor comes on and the pressure drops. Although, this happens without cold air coming out of the vent (just that sort of humid air that is charecteristic of no cooling happening). The RPM does drop when the compressor comes on. Do you have any ideas what could be causing this?
Thanks

Hi,

I drive a BMW X5 E53. My problem is the vent blows only warm air (depending on the outside temp). When I checked usig the knowledge what i got from reading different posts I found that the Clutch doesn't get engaged. When I unplug the sensor from the high pressure line (i have a 3 wire sensor) the Aux fan starts and as soon as i plug the sensor back it stops. But could never get the clutch engaged. Also what I would like to check now is to find the relay which switchs the clutch on/off and short it as per the video attached. (How To Make AC Ice Cold, Recharge air, and Force the Compressor Clutch to Engage - YouTube ).

Does anyone know where is the relay for the E53 located? And how to get to it. And is it the Final Stage Resistor in a BMW's case that acts as a relay?

Any help is much apprecieated.

Cheers

My money is on the compressor - either it has shat itself or the clutch is not engaging.

And from your original picture question, the first plug is the only one that connects to the aux fan. If you jiggle the second one around you'll find it pops out and has no electrical connection to the aux fan at all - it is a sensor and is only clipped into the aux fan by plastic tabs

If you could hook up one of those refill can of refrigerant with the gauge you can see what type of pressure you have in the system. I think that your system pressure is low thus activating the low pressure switch to prevent the compressor clutch from energizing. If the system pressure is below 1.5 bars the switch will be activated. You will connect the refill can to the low side of the system (Blue Cap). Search youtube video for refilling a system before performing this procedure.