Q: Radiator fans wont turn off unless I turn off the car, why?
Once the car reaches operating temperature, the radiator fans come on, they wont turn off untill the car is turned off, Why and how can I fix this?
Important details to note, I've replaced the radiator cap, thermostat, water pump, radiator, radiator fans, three fan relays, (coolant temp sensor oem) and (temp sender oem) sensor and I performed an coolant flush with the car tilted and many burping techniques to remove air. Recently, I've removed the battery for 15 minutes in an attempt to refresh the ECU to no avail, problem still occurs. On two separate occasions I timed the fans after driving to see how long they will stay on for, once was for 10 minutes straight, I turned the car off. The second time, the fans ran for 20 minutes straight, I turned the car off. It is my hope, this is enough information. Thanks in advance.
My car has 147590 miles.
My car has an automatic transmission.
It sounds like you have checked just about everything that controls the fans other than the fan power relay itself. As you may know the coolant fan relay turns the fans off and on by receiving information from the coolant temperature sensor at specific temperature thresholds. When this relay is not working properly, this can cause the fans to come on intermittently, stay on all the time or sometimes not at all. When this happens you will notice a temperature spike and drop occasionally as the fan comes on and off. I would suggest having an expert from Your Mechanic come to your home to diagnose your coolant fan.
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