Audi A3 AC System Failure: DIY Check Before Repairs

Had a similar issue with my 2015 Audi A4 2.0 TDI. The symptoms matched exactly, no AC activation and lack of cold air. The problem turned out to be a combination of issues that required professional diagnosis. The main culprits were a faulty AC pressure switch and a significant refrigerant leak from one of the system valves. The pressure switch was preventing the compressor from engaging as a safety measure. When checking the refrigerant levels, the system was completely depleted. The repair involved: Replacing the defective pressure switch, Pressure testing to locate the exact valve leak, Replacing the faulty expansion valve, Full system evacuation and recharge, Testing AC efficiency after repair This was definitely a serious repair requiring specialized AC diagnostic equipment. The issue would have caused permanent compressor damage if left unattended. After the fix, the AC performance returned to factory specifications. For your A3, strongly recommend getting a proper diagnosis with specialized AC testing equipment. The symptoms suggest either a pressure switch failure or refrigerant leak, both requiring professional attention.

Thanks for sharing your experience. Having the exact same headache with my A3 right now. Our AC problems sound really similar, especially with the compressor not engaging. Getting it checked next week since I want to avoid any permanent damage to the system. Can I ask how much the total repair cost you after all the AC diagnostics and parts replacement? Also wondering if youve had any cooling system issues pop up since the fix?

Since having the AC diagnostics and repair work done, the cooling system has performed flawlessly. The full repair cost me 1000 Euro, which covered fixing defective valves in the air conditioning system. While it wasnt cheap, avoiding permanent compressor damage made it worthwhile. The blower motor runs quietly now and the AC maintains perfect temperature. No refrigerant leak issues or strange AC noise have occurred in the months following the repair. Getting a proper professional diagnosis definitely saved me from more expensive problems down the road. The comprehensive AC service included pressure testing and refrigerant recharge, which helped identify all the failing components. If your symptoms match what I experienced, investing in proper repairs now will prevent more costly damage later.

The mechanic visit went much better than expected. After dealing with the AC diagnostic tests, they confirmed it was indeed a faulty pressure switch and low refrigerant, just like your case. The total repair came to 950 Euro, which included replacing the AC relay and pressure switch, plus a full system recharge. The AC maintenance was completed in one day and the cooling has been working perfectly for the past month. No strange AC noise or efficiency problems since the fix. Really glad I didn't wait longer, as the technician mentioned the compressor was at risk of failing completely. Thanks again for sharing your experience. It helped me understand what to expect and avoid getting overcharged for unnecessary repairs. Sometimes paying for proper AC diagnostics early saves much bigger headaches later.