Passat Hybrid AC Failure: Compressor Warning Alert

Had almost the exact same issue with my 2021 Passat GTE. As someone with some experience working on cars, I initially thought it was a refrigerant leak or AC compressor problem, but it turned out to be the AC control unit. The cooling system completely stopped working, showing similar symptoms to yours. After the initial diagnosis, the workshop found that the control unit was the culprit, not the compressor itself. The repair took about 4 hours total, and cost me 980€ including parts and labor. The car air conditioning works perfectly now, but getting the right diagnosis was key. The AC unit issues in these hybrids can be tricky because of the integration with the electric powertrain cooling systems. Could you share: Any specific error codes you received? Does the AC fan still run when you turn the system on? Have you noticed any unusual sounds when trying to engage the AC? What is your current mileage? This information would help determine if your issue matches what I experienced and could save you some diagnostic time at the workshop. The good news is that once fixed, I havent had any recurring problems with the AC system in the past year.

Last service was just 2 weeks ago, and with 52486km on the odometer I can confirm I am experiencing the same symptoms. The AC compressor does not engage at all. The error codes I got were P0645 and P0562, which as you mentioned could point to control unit issues rather than a mechanical AC system failure. The vehicle HVAC fan does still run, but no cold air comes through. There is a faint clicking sound when engaging the air conditioning, followed by absolutely nothing. I will look into having the control unit checked first before assuming a complete automotive cooling system overhaul is needed. Did your workshop mention if this is a known issue with the hybrid cooling integration? Wondering if I should take it to a specialized hybrid service center or if any certified automotive AC repair shop can handle the diagnosis.

Thanks for the additional info. Those error codes definitely match what I experienced, P0645 and P0562 are typical control unit communication issues in these Passat hybrids rather than mechanical compressor failures. The clicking sound you described is identical to what my car was doing. Its the control unit trying but failing to engage the car air conditioning compressor. The regular HVAC fan operation with no cooling is another telltale sign that matches the control unit failure pattern. Given your low mileage and recent service, I strongly suspect youre dealing with the same AC unit issues I had. The hybrid cooling integration makes diagnosis trickier, but any certified VW workshop should be able to handle it, they just need the right diagnostic equipment for hybrid systems. My repair involved: Control unit replacement, System diagnostic reset, Auto refrigerant recharge as a precaution, Full system test cycle One tip: make sure they check the communication between the hybrid management system and the AC control unit during diagnosis. In my case, this connection was the root cause, not the control unit hardware itself. The repair should take 3-4 hours once they have the parts. Costs typically run between 800-1000€ depending on parts availability and labor rates. The automotive cooling system integration in these hybrids is actually quite robust once properly repaired. Mine has been flawless for over 15000km since the fix.

Thank you for clarifying those points. Those error codes combined with the recent service history definitely help narrow down the issue. Will schedule an appointment with the certified VW workshop this week since they should have the right diagnostic equipment for checking the hybrid system integration. The clicking sound followed by no response really worried me at first, but hearing that it matches your experience with the control unit failure makes me feel better about not needing a full auto AC repair job. I was concerned about facing a complete AC compressor replacement which would have been much more expensive. Based on your repair timeline of 3-4 hours and costs around 800-1000€, I can better plan for the service visit. The air conditioning repair should be manageable within my budget, especially if its just the control unit rather than major mechanical components. Will make sure to ask them specifically about: Testing communication between hybrid management and AC systems, Checking the control unit connections, Running a full diagnostic reset after repairs, Verifying refrigerant levels Really appreciate the detailed information about your repair experience. It helps knowing this is a fixable issue that others have successfully resolved rather than a major car air conditioning system failure.