VW Polo AC Compressor Issues: Costs & Warning Signs

Had the exact same auto AC repair situation with my 2016 Golf TDI last summer. Based on my experience with several vehicle HVAC systems, these issues can be tricky to diagnose correctly. Initially thought it was a refrigerant leak when the AC stopped working and got the warning light. The workshop ran a full diagnostic and found the AC control unit was completely dead. No response from the controls and the compressor wasnt getting proper signals. Got it fixed at a specialized automotive cooling workshop. Total cost was 980€ including: New control unit, Programming, System test, Refrigerant check and top-up The repair took about 4 hours. Since then, the AC has worked perfectly with no issues. What diagnostic codes are you getting? Also, does your compressor make any noise when you turn the AC on? This info would help determine if youre dealing with the same control unit failure or a different AC unit issue. Before spending money on parts, get a proper diagnosis. These systems are complex and symptoms can be misleading. Would you mind sharing: Exact error codes from diagnostics, Whether the compressor engages at all, Any unusual sounds, When the problem first started, If refrigerant levels were checked

Thanks for sharing your repair experience. Got my latest service done at 135000km, just weeks before this car air conditioning failure started. The error code I got was P0645. The AC compressor does engage but makes a loud rattling sound for 2-3 seconds before shutting off. When checking the auto refrigerant levels, the workshop found them normal but noticed metal particles in the system. Sounds like my issue might be mechanical rather than electrical, unlike your control unit problem. Did your compressor make any unusual noises before the complete failure? Just trying to understand if I should prepare for a full compressor replacement or if there might be a less expensive solution.

Thanks for those details. Your symptoms definitely point to a different issue than what I experienced with my Golf TDI. While my car air conditioning problem was electrical, those metal particles you mentioned are a classic sign of internal compressor wear. My compressor never made rattling sounds, it just stopped responding completely due to the control unit failure. The noise you describe, combined with metal debris in the system, strongly suggests mechanical failure of the AC compressor internals. Unfortunately, this type of auto AC repair typically requires: Complete compressor replacement, Flushing the entire system to remove metal particles, New receiver drier, Fresh refrigerant charge Based on my research when dealing with my own vehicle HVAC issues, leaving metal particles in the system will damage any new compressor you install. A proper air conditioning repair in this case needs to address both the failed part and system contamination. Cost was around 1200€ for my control unit fix, but compressor replacement with system flush typically runs 1800-2500€ depending on parts availability and labor time. Would strongly recommend getting this addressed soon, those metal particles circulating through the AC unit issues can cause additional damage to other components if left unchecked.

Thanks for the detailed response. After reading about automotive cooling system repairs, I think I need to accept this will be a significant repair job. The P0645 code plus metal contamination really tells the full story. I called a few workshops that specialize in car air conditioning repairs. Most quoted between 2000-2300€ for: New AC compressor, Complete system flush, All required fittings and seals, Fresh refrigerant charge, Labor costs Booked it in for next week since I want to fix this before summer hits. The rattling has gotten worse over the past few days, so waiting longer probably isnt smart. At least now I know what to expect cost-wise and understand why the entire system needs attention, not just the compressor. Just hoping this repair will last and the auto AC system will work reliably afterward. The cooling system problems are definitely more complex than I initially thought. Really appreciate the information about system contamination, helped me understand why a simple compressor swap wouldnt be enough.