What Causes the Engine's Low-Speed Fan to Not Rotate?

[CassandraDella]

Reasons why the engine's low-speed fan does not rotate: Relay malfunction: If the coolant temperature meets the requirements but the car's radiator fan still does not operate, the issue could lie with the fan's relay. A faulty relay can prevent the radiator fan from functioning. Coolant temperature not reaching the threshold: Modern car radiator fans typically operate using electronic temperature control. Therefore, the fan will only start rotating normally when the engine's coolant temperature reaches the required level. Thermostat switch failure: If neither of the above issues is present, the thermostat switch should be inspected. This component can sometimes develop faults, which may affect the operation of the car's radiator fan. Hence, it is important to check this as well.

[JonathanMarie]

After all these years as a mechanic, I've encountered countless cases of low-speed fan failures. There are several common causes that need to be checked one by one. It could be a faulty temperature sensor failing to send signals when the fan should activate; or a seized/burnt-out fan motor due to aging causing rotation issues; poor relay contact failing to control the circuit; blown fuse cutting off current; short circuits, broken wires, or corroded/loose connectors may also be factors. During inspection, start the vehicle and observe the fan status after engine warms up. Simple checks like replacing fuses in the fuse box might help. If still not working, professional equipment is needed to test sensor voltage and motor resistance. Non-functioning cooling fans are extremely dangerous as they can cause engine overheating and cylinder seizure, leading to costly repairs. Regular maintenance like radiator cleaning and proper coolant replenishment can prevent many such issues.

[CassandraLee]

Recently, my car's low-speed fan stopped working, which is really annoying. It could be that the fan control module is broken and unresponsive, or the air conditioning-related sensors are falsely triggered and not sending signals. I opened the hood myself, checked the fan connector for looseness or overheating, and also looked to see if the fuse was blown, trying a new one. Aging wiring or a seized fan bearing could also be the root cause. A friend suggested going to the 4S shop to scan for fault codes with a diagnostic tool to avoid misdiagnosis and unnecessary disassembly. If the fan doesn't work, the engine temperature can skyrocket in summer traffic, posing safety risks and increasing fuel consumption. Make it a habit to blow dust off the radiator during car washes to maintain ventilation and get timely repairs—don't delay.

[Madelyn]

If the fan doesn't rotate at low speed, it's mostly caused by signal interruption from a faulty temperature sensor, preventing the fan from receiving the start command. Worn brushes or carbon powder buildup inside the fan motor can also cause it to jam. In terms of wiring, poor grounding or corroded connectors may lead to unstable current. Quickest check: Observe the fan's behavior after the engine warms up. If it doesn't move, first replace the fuse and check the relay. Handle minor issues yourself to save time; for major ones, visit a shop to test voltage. Ignoring this may cause the fan to stop, leading to engine overheating, cylinder seizure, and costly repairs.

[DelCharlotte]

As a car owner, I'm very concerned about the risk of the fan not spinning at low speeds. Possible causes include aging sensors sending incorrect data, loose fan belts causing poor transmission, or deformed fan blades obstructing rotation. Checking the fuse in the circuit is the easiest first step. For routine maintenance, it's recommended to replace the coolant and clean the system before summer to prevent critical failures. A malfunctioning fan not only causes engine overheating and component damage but also compromises driving safety – breaking down on the road would be a real hassle. Visit a repair shop immediately to have technicians test the control module and wiring for quick fixes to ensure safe travels.