radiator fans
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radiator fans
Hello I have a 2011 f150 3.5 ecoboost with 150k miles. I have 2 coolant radiator fans. The only time the fans turn on are when I have AC on or temp reaches 215f. That is the only time that they both turn on. I have never seen just one turn on. I have left hood open and sat there to check it out. Is this normal? should 1 fan fan turn once in a while or is always Both? 215f and AC on is when it they both turn on only. thanks
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The fans should be both OFF, both in low speed, or both in high speed. Never only one operating. I posted the following in another thread just last week:
Sounds like your low speed switching circuit is malfunctioning. Could be as easy as a fan control relay that's failed. Also, check fuse F63 under the hood.
In low speed, they are connected in series so they work at half power. In high speed, they are switched to a parallel configuration and both receive full battery power. IOW, there is no low speed or high speed specific fan, they both should be working all the time (when activated).
Last edited by ProjectSHO89; Jan 26, 2023 at 12:14 PM.
Thread Starter
Junior Member
Joined: Jan 2022
Posts: 5
Likes: 0
The fans should be both OFF, both in low speed, or both in high speed. Never only one operating. I posted the following in another thread just last week:
Sounds like your low speed switching circuit is malfunctioning. Could be as easy as a fan control relay that's failed. Also, check fuse F63 under the hood.
Sounds like your low speed switching circuit is malfunctioning. Could be as easy as a fan control relay that's failed. Also, check fuse F63 under the hood.
5 Year Member
Joined: May 2019
Posts: 3,751
Likes: 1,117