VW Golf Hybrid AC Compressor Failure & Warning Light Fix

Having worked on my 2019 Golf GTE with a similar vehicle HVAC issue, I can share my experience as someone with moderate car repair knowledge. The symptoms you describe match exactly what happened with my hybrid, complete AC failure and warning lights. Initially thought it was a refrigerant leak, but the diagnostic revealed a failed AC control unit. The module was no longer communicating with the AC compressor. The repair involved: Full diagnostic scan, Removal of dashboard components, Replacement of the control unit, System reset and refrigerant pressure check, Final testing of all AC functions Total repair cost was 980€ at an authorized workshop. The whole process took about 6 hours since they had to partially dismantle the dash. They found the control unit failure was due to an internal electronics issue, not related to the cooling system components themselves. To better assist with your specific case, could you share: Any diagnostic codes showing? Does the fan still work on any speed? When exactly did the problem start? Any unusual sounds before failure? Have you had any previous AC repairs? This would help determine if you are facing the same control unit issue or potentially a different AC compressor problem.

Thanks for sharing your diagnostic experience. My car just had its 50000km service last month, so this issue is quite recent. After checking the error codes again, I get P0645 which seems to point specifically to the AC compressor circuit. The fan still works fine on all speeds with no unusual sounds, but the actual cooling just stopped working completely two days ago. The cooling system was working perfectly fine before this, no prior AC repairs or refrigerant top-ups needed. Given your experience with the control unit, I will definitely have them check both the electrical and mechanical components of the air conditioning repair. Based on the diagnostic code, I am leaning towards an electrical rather than mechanical failure of the AC unit.

Thanks for those additional details about your Golf Hybrid AC issues. The P0645 code does typically indicate an electrical control circuit problem, similar to what I experienced with my GTE. Since your symptoms mirror mine, working fan but no actual cooling, and considering the error code relates to the AC compressor circuit, I strongly suspect the control unit is the culprit here too. The fact that your cooling system stopped suddenly without warning sounds or prior issues also matches the electrical failure pattern. One key difference I notice is your car had recent service work. Worth checking if anything was disturbed near the AC control unit during that service. In my case, the auto AC repair revealed some corroded connections at the control unit, possibly from condensation buildup over time. A full diagnostic check focusing on the electrical components should be your next step. My repair costs might give you a rough estimate, but prices can vary based on parts availability and exactly what needs replacing. Just make sure they verify the refrigerant system integrity while they are in there, no point fixing the electrical without confirming there are no cooling system leaks. Let us know what the workshop finds. Would be interesting to see if it turns out to be the same control unit issue as my GTE had.

Thanks everyone for the insights. I called the workshop and scheduled a full diagnostic for next week. They mentioned checking both the AC compressor circuit and control unit based on the P0645 code, which matches what you experienced. The auto AC repair estimate they gave was around 850€ if it is indeed the control unit, possibly more if they find additional automotive cooling system issues. They quoted about 5-6 hours labor time, which aligns with your repair experience. Will update once I get the car back and know exactly what caused the air conditioning failure. Really hoping its just the control unit and not a more complex issue with the AC compressor itself. At least the fan still working normally gives me some confidence its primarily an electrical rather than mechanical problem. Thanks again for helping me narrow down the likely causes. Having your real-world repair experiences made me feel better prepared for the workshop visit.