Suzuki Alto A/C Complete Failure + Compressor Warning

Had the same issue on my 2018 Suzuki Swift last summer. The symptoms matched exactly, A/C stopped working completely with error codes present. Initial diagnosis revealed an undervoltage condition affecting the A/C compressor. The root cause was a failing pressure sensor in the HVAC system, which triggered a safety cutoff. These sensors prevent the compressor from running when refrigerant pressure is too low, usually due to a refrigerant leak. Once the pressure drops below the threshold, the system shuts down completely. In my case, the fix required: Testing the pressure switch functionality, Checking refrigerant levels, Replacing the faulty pressure sensor, Recharging the A/C system This was definitely a serious issue that needed immediate attention to prevent A/C compressor damage. The complete shutdown is actually a protective measure built into modern vehicles. Consider having it checked soon, these symptoms typically dont resolve on their own and can lead to more expensive repairs if left unchecked. A certified A/C specialist can properly diagnose using the error codes and pressure testing equipment.

Thanks for describing your experience with the Swift. My Alto had exactly those symptoms and I just got it back from the shop last week. The AC relay was completely dead and they had to replace the relay switch along with doing a full system diagnostic. The air conditioning works perfectly now. Great to hear the pressure sensor was the culprit in your case, I was worried it might be the compressor which would have been much more expensive. Mind sharing what the repair cost you? Also curious if youve had any other HVAC system issues since getting it fixed?

Great to hear your Alto is working again! Yes, after getting my Swift fixed with the pressure sensor replacement and resolving the undervoltage issue, the A/C system has been running flawlessly. The total repair came to 240€, which included the diagnostic work and fixing the voltage-related problems. The HVAC system has been trouble-free since the repair, no more compressor shut-offs or error codes. Regular maintenance has kept everything running smoothly, and the air conditioning performance remains consistent. Having a properly functioning pressure sensor is crucial since it protects the compressor from damage due to refrigerant leaks or pressure issues. Its definitely a relief when these problems turn out to be sensor-related rather than requiring a full compressor replacement. Proper diagnosis really makes the difference between a simple fix and an expensive repair.

Thanks for the helpful advice. Wanted to share how things turned out with my Alto. After reading about the pressure sensor issues here, I visited a certified A/C specialist this time instead of my regular mechanic. The total repair came to 180€, which included replacing the faulty relay switch and running a complete A/C system diagnostic. They found no refrigerant leaks or pressure sensor problems, which was a relief. The compressor itself was in good shape, it just wasnt getting the signal to engage due to the bad relay. The A/C has been working flawlessly for the past week. The shop also showed me what to watch for in case of future issues. Much cheaper than I expected and the cooling performance is actually better than before. Really glad I got it checked out quickly before any major components could get damaged.