VW Jetta TDI AC Compressor Failure Warning Signs

I had a similar issue with my 2014 VW Passat TDI last summer. As someone with moderate car repair experience, I initially thought it was just a refrigerant leak when the air conditioning stopped working. The symptoms were identical to yours, no cold air, warning lights, and the cooling system refusing to engage. After bringing it to my trusted workshop, they diagnosed a defective air conditioning control unit. The entire repair, including parts and labor, cost me 980€. They completed the work in about a day and a half. The car air conditioning has worked flawlessly since the repair. The technician explained that these control units can fail due to various factors, including electrical issues and general wear. To better assist with your specific case, could you share: Have you noticed any unusual sounds when trying to engage the AC? What error codes is your car showing? How long has the problem been present? Have you had any previous air conditioning repair work done? This information would help determine if your issue is similar to what I experienced or if it might be something else entirely.

My Jetta has 17438km on the odometer and was just serviced last month. The AC started making a loud clicking noise when engaging, then completely stopped working. The error codes I got were P0645 and P0410. I did notice some oily residue near one of the AC lines, which might indicate a vehicle HVAC leak. I have not had any previous auto AC repair work done on the car. The noise started about 2 weeks ago, and the system completely failed 3 days ago. Given the oily spots, Im worried this could be more than just a control unit issue, possibly pointing to a more serious refrigerant leak or compressor problem.

Thanks for providing those additional details about your Jetta. After seeing your description of the oily residue and clicking noise, this actually sounds very similar to how my compressor failure started developing. The clicking noise followed by complete failure is a classic sign of compressor problems, and the oily spots near the AC lines strongly suggest a refrigerant leak in the cooling system. While my initial issue appeared similar, the fact that youre seeing visible oil traces makes me lean more toward a mechanical failure rather than just a control unit problem. When my compressor eventually failed completely, the repair involved: Replacing the compressor unit, Flushing the automotive cooling system, Installing new refrigerant, Replacing seals and O-rings The total cost came to around 1450€, considerably more than just a control unit replacement. The repair took about 2-3 days because they had to ensure the entire air conditioning system was properly cleaned to prevent any debris from the failed compressor from causing future issues. The P0645 code typically relates to the AC compressor clutch circuit, which aligns with the clicking sound you described. Combined with the visible leak, you likely have both an electrical and mechanical issue with your compressor assembly that will need addressing. Would recommend getting this checked soon, as continuing to run the system with a refrigerant leak could cause additional damage to other vehicle HVAC components.

Thanks for the detailed feedback about the compressor issue. The clicking noise and oil residue definitely help explain why my symptoms differ from your control unit problem. Based on the error codes and your repair experience, Im preparing for a potentially bigger repair bill than initially hoped. Your case with the full system flush and compressor replacement makes a lot of sense given what Im seeing. The automotive cooling system in my Jetta will likely need similar treatment. At least now I have a better idea of the costs and timeframe, looking at around 1450€ and 2-3 days of shop time seems reasonable for such an extensive auto AC repair job. Think Ill schedule the repair next week to avoid any additional damage from the refrigerant leak. Really appreciate you sharing your experience, its helped me understand what Im likely dealing with and what to expect during the repair process.