A/C Issue, blowing hot air, FSR issue?
 

So I'm back! After the car running great, I noticed 2 things:

Well some backstory first, I have replaced the FSR 2 separate times in 1 year.

Last week the A/C stayed on after turning the car off. When I mean turned on, it showed the display with 16ºC instead of the 60ºF, and pushing the buttons on the display did NOTHING. The fan wasn't blowing at all when it did this. I removed fuse #45 and the display turned off. Replaced fuse and the following day the A/C started only blowing hot air. I don't think the clutch is coming on anymore either. I noticed the aux fan was not coming on either, and thought it might have gone out...again. I had the Aux fan and Clutch replaced last year for almost $1000 dollars at a mechanic with 1 year warranty (could have already passed warranty because it was in July when I replaced it). Anyways, the other night, I got out of the car and heard the fan spinning and saw it physically spinning. SO I jumped back in and turned it on and turned the A/C. Still hot air! I drove it around, still hot air. Came back and parked it and the fan had gone off! UGH!!

So I thought, well maybe the refrigerant was out. I went to autozone and bought a can of R134a with the gauge. When I plugged in the gauge, the needle did a complete spin and lodged itself underneath the 0psi starting point (there was a pin to hold the needle) So It seemed WAY over pressurized. I released pressure and got it down to 0 PSI. Started putting the can in. 2 short squirts and it was overpressurizing again. WTF? The can is full of refridgerant, I couldn't have put that much in already! I released the pressure and placed it to the recommended level. Still, hot A/C. At this point, I'm stuck. Where do I look for replacements?

Side note: the Thermostat appears to be stuck open, and I am in the process of purchasing a new one in a few weeks when I get paid again. Amazon has the Thermostat, Temperature sensor, Aftermarket complient coolant and shipping for about $120 total. I plan on doing it myself. But my question is, could the thermostat be causing the A/C problem? I notice my gauge on the temperature reads at the 1/4 mark, not the halfway mark very often, even after driving for a while. I took a roadtrip Tuesday night to Fresno (about 200 miles away) and the temperature only got up to halfway once in the whole trip.

Anyone have a clue? 2001 BMW X5 3.0i 06/2001 build date.

Thanks!

It might be the HVAC head unit. You might need somebody with the right software setup to get to the bottom of this problem.

Can you clarify, what is the HVAC head unit? Where is it located?

Was the engine running when you tried to put the refrigerant in? Are you sure you got the connector all the way in?

I know they make the new connector basically idiot proof, but there's always an idiot that comes along and some how manage to circumvent the idiot proof ideas of the best engineers.

The low pressure port is the one with the smallest fitting.

It's a bayonet fitting on the connector, you need to pull back on the outer ring and insert the fitting into the low pressure shraeder valve. Once it's fully seated release the outer ring.

Well thanks for that vote of confidence and that IQ bashing, but yes I did make sure the connector was firmly in place on the correct port. Like I said the system was way over pressurized, and I released pressure down. The gauge basically had a white, green and red section, and I released it down to the white section, pushed the button down for a total of .25 seconds and it filled all the way to the red. the system has too much pressure for some reason.

If you are getting that kind of reading on the low side I would say that your compressor valve on the low side has taken a dump.

I'm guessing I need a new compressor then?

Base on what you posted yes, but I would hook up a complete ac manifold gauge set and check the low side pressure and the high side pressure. If the compressor did take a dump you will need to flush out the evaporator and condenser or else you will ruin the new compressor. You will need to also replace the dessicant or drier in the system depending on what you have.

Careful with that reading on the low side because a can of refrigerant is not made to with stand 300PSI. That is why people caution diyers not to open the high side valve when they are charging the system

Can you post a picture of the bayonet fitting that you are using to refill the system with refrigerant? Does it have a knob that you can twist once the fitting is connected to the system? If you do have a knob you need to turn that knob clockwise to open the shraeder valve and before removing the fitting you need to turn it counter clockwise to close the shraeder valve.

Not to hijack this thread but, any update on your ac issue? My 2003 3.0i has the same issue blowing hot air and had high pressure.... It worked fine in the morning going to work and when starting up to go home, only hot air. I released the pressure to the green area on the gauge and nothing.
I was going to start with the least expensive trigger point and replace the high pressure switch. It's only $35 online and go from there.

Thoughts?

If you didn't add refrigerant to the system there is no reason to release refrigerant from the system because the low side reading is too high. The high side pressure switch is only there to disengage power to the compressor to stop it from building up too much pressure in the system.

Was the compressor running when you read the "Green" gauge? Compressor has to be running in order for the low side pressure to decrease because that is the "Suction" side.

Gotcha...no, the clutch was not engaged. The auxiliary fan wouldn't come either and I physically checked the fuses but, haven't with a meter. Will confirm they're condition with a meter this weekend. I suspect it's either the fan or compressor but, wanted to get input as to what possibly is the culprit. Its too damn hot down here to go without ac.

Thanks!

So you bled down the low side so that it match the "Green" Gauge mark without the compressor engaged. Hate to tell you but you are now low on refrigerant. The system could be so low that it won't allow the compressor to turn on.

If you have some BMW scanning software such as BMW 1.4 or Carsoft 6.5 or INPA, you can check to see if you have a fan fault or other problem with the HVAC system.

HVAC head unit...it's referring to either the IHKA or IHKR control panel...the unit in the dash that allows you to direct air flow & air temperature etc. :)

IHKR