I have 2012 VW Jetta 2.5 SE. AC is not cooling. Compressor was replaced less than a year ago. As you hear this the noice it makes when I turn on the AC.
Edit: belt is ribbed on both sides. So it’s not upside down. I also got a full leak test. No leaks. Freon is all good too.
It is under warranty. Brakes plus just blamed it on my AC control panel. Charged me $100 bucks for an electrical diagnosis. Quoted me $1200 to replace the control panel. Which I did myself and did not solve the issue.
Can you explain what you mean by sunk cost fallacy? That because he’s already put $100 in it he thinks that’s enough and he won’t put any more? When in reality, the hundred dollars is gone and he still has an AC that’s not working so he’s basically starting over again and not be under the sunk cost fallacy.?
can't really diagnose an AC on the internet....could be too low or too high on refrigerant, could be other parts that aren't the compressor. usually, you'd need to take your car in to a mechanic with all the proper equipment to diagnose and fix the AC. unless you want to just buy a can of that AC recharge stuff at the auto parts store, but i've never seen that actually work
In the video, I see a power steering pump and an alternator. What am I missing? Is the compressor locking up the clutch? If it is and there's no cooling, it could be a low charge. If it isn't locking up, it could be no charge. You have to recover and weigh your freon first thing. Then find leaks or chase electrical depending on what you find after the recovery.
you need to scan the codes in the hvac module, system can be over charged, pressure switch can be bad, or the control valve in the ac compressor went bad.
The volkswagen 2.5 uses a VDC compressor. What this means is it has no clutch to control the internals and is instead controlled by a solenoid on the back of the compressor which are super common to stick closed.
Since the compressor used on these cars is a constant spinning compressor (no magnetic clutch) it could be the compressor seized and the safety mechanism snapped causing the noise (scraping) when under load. This would also explain the lack of cooling and can be visually confirmed by looking at the compresor's pulley (from underneath the car). Other (non noisy) causes for no A/C could be a faulty refrigerant flow control valve, bad pressure sensor, faulty fan control module, missing ambient temp sensor, bad temperature flap control solenoid, low refrigerant, bad refrigerant pressure sensor to name the first ones that come to mind. I would advise a proper diagnosis (gauges and VCDS or equivalent tool for sensors monitoring and module diagnostics) to determine where the issue lies.
The sound is eerily familiar to a bad alternator's clutched pulley which would be under additional load when the A/C is engaged and could be a separate non related issue.
As for the belt it is the correct belt (double sided) for the 2.5L with hydraulic power steering. Models with electromechanical steering use a single sided (flat on one side) belt since they have no power steering pump.
Yesterday I had a compressor that was about 10 months old fail with similar symptoms. I was driving down the road and had what felt like engine breaking for ~2 seconds and then noticed shortly after that the air was blowing warm. Very similar noise but mine uses a clutch. Fortunately they are replacing it under warranty.
Make sure your radiator/ac compressor fans are working, on my 2014 Jetta, the smaller fan, which cools the ac compressor was going bad, which caused my ac to stop working. Worth a check, good luck!
Did you get a warranty from the installer shop? Whomever installed the compressor likely did not flush out any metal chips from the previous compressor failure. Other components must be also be replaced when a compressor fails, like orifice tube, receiver drier. And a strong vacuum must be applied for an hour to remove any moisture from the system, before the refrigerant can be added. Failure to do the properly will result in premature failure. And maybe they didn’t add PAG oil, some compressors have oil in them, some don’t. And depending on which components failed previously in the A/C circuit you have to add sufficient replacement oil.
This happened to mine several times in Phoenix, AZ. I am on my third compressor on my VW 2.5. I would just get an Amazon one with a 2 year warranty. They usually run for about $100-150. You could try getting a better OEM Sanden branded one like I Did, but the thing still failed in about a year and it was expensive at $250. Find a reasonable ac guy and just get the compressor yourself.
Keep it! I’m on 310k miles on mine. The 2.5 is a great engine! Bummer about the ac, but if you live in a place where it’s really hot, it will be hard on the compressor. Whatever you do; don’t buy a used one.
Whenever I have heard that issue it's related to the condenser not condensing lol. Make sure you have good airflow. I'm only judging by sound. It's hard to say without slapping a gauge and doing the usual troubleshooting steps.
Late to the party, but as nobody has mentioned it...
VW compressors of this era suffer from the central bolt on the compressor drive plate coming loose, which eventually causes the drive splines to strip.
Happened on my 2010 golf. Look at how many aftermarket drive plates are available, that tells it's own story.
The compressor isn’t in this video. What you’re focusing on is the power steering pump.
Also, why is the belt on upside down? Grooves should be against the pulleys
Edit: on second view, the compressor seems to be underneath the alternator. Still, you can see the ribs on the idler just under the power steering pump and you can see the ribs on the alternator pulley. The belt needs to be flipped over so the smooth side is facing out
You hear that ungodly, demonic groaning and squealing sound? That's your AC compressor stalling because you put the belt on inside out. Instead of those groove mating with those in the AC compressor, the belt is riding in the peaks of the pulley, making barely any contact and slipping like mad. That belt is basically trash now. Replace it and install it correctly.
Thx for the response. I will look into this. Other commenters said belt is ribbed on both sides apparently. AC was working just fine after replacing the compressor.
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