What is the reason for the Citroen C3XR fan not stopping after turning off the engine?
2 Answers
There are several reasons why the fan of the Citroen C3XR does not stop after turning off the engine: 1. Insufficient coolant causing high water temperature, leading to the fan running continuously. 2. The thermostat fails to open, preventing water circulation and causing high water temperature. 3. The water temperature sensor is damaged. 4. The fan relay is damaged. The functions of the cooling fan include the following: 1. It is part of the car's cooling system: The radiator in the engine's water cooling system consists of three parts: the inlet chamber, outlet chamber, main plate, and radiator core. The coolant flows inside the radiator core, while air passes outside the radiator core. The hot coolant cools down by dissipating heat to the air, while the cold air heats up by absorbing the heat from the coolant, making the radiator a heat exchanger. 2. The radiator also serves as a water storage and heat dissipation device: The car radiator cap is equipped with an air steam valve and a common vent hole connected to the atmosphere. When the water temperature rises, the coolant in the car radiator expands, and the steam pressure increases, opening the steam valve to release air. When the water temperature drops, the pressure decreases, and the air valve opens, allowing outside air to enter the radiator through the common vent hole, thus maintaining constant pressure inside the radiator. 3. The radiator protects the engine from damage caused by overheating: The principle of the radiator is to use cold air to reduce the temperature of the coolant from the engine inside the radiator. The radiator has two main components: the radiator fins made of small flat tubes and the overflow tube (located at the top, bottom, or sides of the radiator fins).
I also experienced the fan running wildly after shutting down my Citroen C3-XR. Later, a mechanic found it was due to a faulty coolant temperature sensor. This component monitors the engine temperature—if it gives inaccurate readings, the car may think the engine is still hot after stopping, causing the fan to keep spinning like crazy. Also, check if the fan relay is stuck. The relay acts like a switch; if it gets jammed, it can't break the circuit. By the way, if the engine has overheated previously, the smart system might keep the fan running longer to cool it down, but if it doesn’t stop after five minutes, that’s definitely abnormal. My advice: don’t ignore it—check the circuit and sensors ASAP, or your battery might drain, making it hard to start next time.
