V70 Overheating Speed Sensor

I had a similar issue with my V70. Does this sound familiar? When did you last check the coolant level? I noticed that when the coolant was low, the fan wouldn't kick in properly, causing overheating. Also, does the fan spin freely when you try to rotate it by hand? Maybe the fan motor is failing?

Thanks for the quick reply. The coolant level is perfect, I checked it yesterday. The fan spins freely by hand without any resistance. If the speed sensor is bad, would that stop the fan from turning on, even when the engine is clearly getting hot?

For me, a faulty speed sensor stopped the fan from turning on. The fan motor was fine, but the ECU wasn't getting the right signal to start it. Given what you've checked, I'd suggest getting the sensor diagnosed by a professional. It might save you from chasing other problems.

Thanks for the advice. A mechanic checked it, and you were right: the speed sensor was defective. I replaced it, and the fan's running smoothly now. The repair cost 250€. I appreciate you sharing your experience!