T-Cross AC System Dead: Relay vs Compressor Issues

Had similar issues with my 2016 VW Tiguan last summer when the AC system failed completely. The symptoms matched yours, no response when pressing the AC button and zero cooling. A diagnostic scan revealed the AC relay was failing to engage the compressor due to an undervoltage condition. The pressure sensor was sending incorrect signals, causing the system to shut down as a protective measure. This is actually a common failure point in these models. The repair involved replacing both the AC relay switch and the pressure sensor. While not the most expensive AC repair, it requires proper diagnostic equipment to verify the exact cause, as multiple components can trigger similar symptoms. The fix restored full functionality to the air conditioning system. Important to address this promptly, as continued attempts to run the system with a faulty relay can potentially damage the compressor. The pressure sensor issue tends to develop gradually over time rather than fail suddenly. If you notice the cooling becoming inconsistent before complete failure, this often points to the sensor/relay combination rather than a major compressor problem. Consider having a specialized AC diagnostic performed, unusual parts replacement without proper testing often leads to unnecessary expenses in these systems.

Thanks for sharing your experience. This sounds exactly like what happened to my T-Cross. The AC system suddenly stopped working and I had similar error codes showing up. In my case, the mechanic first suspected a refrigerant leak but after proper testing found it was indeed the relay switch causing the HVAC system to malfunction. The A/C compressor itself was fine, which was a relief since that would have been much more expensive to replace. How much did the repair cost in your case? Also wondering if youve had any cooling issues since the fix? Mine has been running perfectly for about 6 months now but I keep an eye on the cooling performance just in case.

The complete repair including parts and labor came to 240€ for fixing the undervoltage issue affecting the A/C compressor shut-off function. The air conditioning system has worked flawlessly since the repair 18 months ago. Like your case, the pressure sensor readings were initially misleading and suggested a refrigerant leak. But proper diagnostic testing revealed the real culprit was the relay switch causing an undervoltage condition. This is why specialized A/C system testing is so important before replacing parts. Regular maintenance has kept everything running optimally since the fix. The cooling performance remains consistent even during peak summer temperatures. No error codes or compressor engagement issues have returned. You made the right call getting it properly diagnosed rather than attempting quick fixes. These voltage-related A/C problems tend to stay resolved once correctly repaired, unlike temporary fixes that mask underlying issues.

Glad to share how my AC repair journey ended up. After getting those helpful replies, I took my car to a different shop that specializes in A/C system diagnostics. They confirmed the belt tensioner was also worn, which contributed to the AC relay issues. The total repair came to 320€ including the new relay switch, pressure sensor replacement, and belt tensioner work. More than the previous response but my system needed that extra fix. The cooling now works perfectly after 8 months. The A/C compressor engages immediately and maintains consistent temperature. Such a relief compared to the headaches with my previous mechanic who just wanted to recharge the refrigerant without proper testing. Really appreciated the advice about getting proper diagnostics first. Saved me from potentially expensive compressor damage and helped me find a shop that actually fixed the root cause.