VW Transporter Fan Not Working, Overheating Issues

I had a similar issue with my 2006 VW Touran, sounds exactly like what you are describing. With some experience working on VWs, I can tell you this type of cooling system problem needs proper diagnosis. In my case, the main culprit turned out to be a defective speed sensor that was not properly triggering the radiator fan. The fan would not engage even when the engine was clearly overheating. There was zero fan noise which made me initially think it was the thermal switch, but the workshop found the speed sensor was the actual problem. The repair cost me 250€ including parts and labor. Since then, the cooling system works perfectly, the radiator fan kicks in exactly when needed and the car maintains proper temperature. Before suggesting specific fixes, it would help to know: Have you checked the coolant level? Does the temperature gauge show accurate readings? Are there any specific error codes showing? Has the car had any recent cooling system work done? Getting this information would help determine if your issue matches what I experienced or if there might be other factors at play. Car overheating issues can have multiple causes, so proper diagnosis is important before replacing parts.

Last service was at 118602km and they found nothing wrong with the cooling system. Just did proper diagnostics today and the fan motor draws no power when tested directly. No resistance readings either, so seems totally dead. Makes sense since there is zero fan noise. The thermal switch tests fine with proper continuity and the coolant temp sensor shows correct values on the scanner. Checked all fuses and wiring, everything looks good there. Really points to just being a bad fan motor in the cooling system. Going to order a new radiator fan assembly tomorrow. The complete unit is 180€ which isnt terrible. Should be a straightforward swap once the new part arrives.

Just saw your update about the fan motor testing, that definitely confirms what I suspected based on my experience. Having gone through a very similar situation with my Touran, replacing the radiator fan assembly was exactly the right call. The lack of power draw and resistance readings matches the symptoms I initially had before replacing my fan unit. The price you found at 180€ is actually quite reasonable, I ended up paying a bit more for mine. Since your thermal switch and temp sensor tested good, and you already verified the wiring, you can be confident the fan assembly is the culprit behind your car overheating issues. The cooling system should work properly once the new unit is installed. One tip from my repair experience: when installing the new fan assembly, double check the electrical connections are fully seated and secure. Poor contact can sometimes mimic a failed fan motor. Also worth inspecting the connector pins for any corrosion while you have everything apart. Let us know how the repair goes once you get the new part installed. The temperature control should return to normal pretty quickly after the replacement.

Thanks for the tip about checking the connections. Makes total sense to inspect everything while I have it apart. The parts should arrive next week. I will definitely report back on the fix. The cooling system issues have been really annoying, so I am looking forward to having proper temperature control again. At least the diagnosis was clear, when the fan draws absolutely no power and shows no resistance, it is pretty obvious the motor is dead. Good thing I did not waste money replacing the thermal switch or other parts first. The complete lack of fan noise was a big clue pointing to the fan motor itself. Will update the thread once I get the new radiator fan installed and confirm it solved the overheating problem.