Why does the Audi A4's fan keep running after the engine is turned off?
2 Answers
This is a normal phenomenon. Although the car has been turned off, the engine temperature remains high. The vehicle's computer will automatically activate the cooling fan based on the engine temperature sensor to perform cooling operations. Below is relevant information about the Audi A4: 1. Introduction: As the first model to introduce the long wheelbase and turbo concept, the A4L has enjoyed enduring popularity from the B5 to the B8 generations. The new A4 model has abandoned the "teardrop" headlight design and added the quattro all-wheel-drive mode, making its appearance more stylish and sporty, with even more outstanding power and handling. The interior craftsmanship is exquisite, featuring rich technological configurations and ample space, offering excellent practicality among B-segment vehicles. 2. Achievements: The Audi A4 produced by FAW-Volkswagen is the first B-segment sedan from an international luxury brand in China, filling the gap in the domestic B-segment sedan market and solidifying FAW-Volkswagen's leading position in the domestic luxury car market. This was quite significant at the time, and judging by the sales of the Audi A4 in China, it has indeed been successful.
My old A4 had the same issue before. Actually, it's the cooling system doing its job. After turning off the engine, the temperature remains high, so the electric fan keeps running for a while to help cool down the radiator—this happens more often in summer after highway driving. But if it runs too long or sounds abnormal, you should check if the coolant temperature sensor is giving false high-temperature readings, or if the cooling control module is malfunctioning. Also, low or degraded coolant can reduce cooling efficiency and trigger this situation. Last time I encountered this, it was due to willow catkins clogging the radiator gaps—cleaning them out fixed it. Short operation is normal, but if it runs over half an hour, it's best to scan for trouble codes.
