Audi S3 Fan Failure Causing Critical Engine Overheating

I experienced identical symptoms with my 2006 Audi A4 2.0T. The car radiator was reaching critical temps, especially in idle, and the cooling fan remained inactive regardless of temperature. Initially suspected the thermal switch, but diagnostic testing revealed a failed fan motor assembly. The fan noise had gradually disappeared over weeks before complete failure. The temperature control module was still functional, but the fan motor itself had burned out. This is a serious issue requiring prompt attention as sustained overheating can lead to head gasket failure or engine warping. The repair involved replacing the complete fan motor assembly including the shroud. The temperature sensor and fan control module should also be tested since they work as a system. Worth noting that a failing speed sensor can sometimes create similar symptoms by sending incorrect signals to the control unit. These symptoms on Audi models from this era often point to electrical issues in the cooling system rather than mechanical failures. Having it properly diagnosed with specialized equipment is essential to avoid replacing parts unnecessarily.

Thanks for the detailed reply about the fan motor issue. The same thing happened to my S3, and replacing the complete cooling system fan assembly solved the overheating problem. The engine cooling is now perfect, even in the worst traffic jams. Quick question, can you remember roughly how much you paid for the repair? Also, has everything been running smoothly since the fix, or have you noticed any other cooling-related issues? Just want to make sure I wont face any surprises down the road with my repair.

Had the same fan motor issue fixed last month. The mechanic found the speed sensor was defective, which explained why the fan blade wasnt engaging properly even when the car overheating warning appeared. Total repair cost came to 250 Euro for parts and labor. The temperature control system has been working flawlessly since the repair. No more overheating issues, even during extended idle periods. The fan noise is now normal and consistent, activating exactly when needed. My previous symptoms of rising temps in traffic completely disappeared after the fix. Looking back, the progressive failure of the radiator fan was probably sending incorrect signals to the control unit for months before complete failure. Getting it fixed was definitely worth the investment to prevent potential engine damage.

The mechanic diagnosed and fixed my overheating issue last week. The radiator fan assembly replacement cost 380 Euro including labor. Turns out the fan motor was completely burned out, just as you described. Since the repair, the engine cooling system has been working perfectly. No more temperature spikes in traffic, and the new fan kicks in exactly when needed. The car running temperature stays steady now, even on hot days. Really glad I asked here first instead of going back to my old mechanic who probably would have replaced unnecessary parts. This targeted fix saved me both time and money. The cooling system is working exactly as it should, and I can finally drive without constantly watching the temperature gauge. Good to know these Audis from our generation share similar cooling system patterns. Thanks again for pointing me in the right direction with the fan motor assembly.