The fuse and relays are all OK, but both fans are just running with a key that has not even been started. You can only stop if the relays are removed or locked. Please help me find a solution.

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    Either the AC sensors or the cooling system sensors are causing the controller to turn the fans on or the controller has failed.
    – Solar Mike
    Jan 22 at 9:51
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    Welcome to Motor Vehicle Maintenance & Repair! What is the vehicle in question? Jan 22 at 14:43

First make sure coolant is full and purged from all air. If temp sensor is surrounded by air and not coolant it will not read correctly. Then make sure all A.C. and defrosters are turned off. Then switch relay with another known good relay. Is your temperature gauge on dash always hot, even when first starting? Check with a scan tool to see if the computer is receiving accurate readings from the temp sensor(s).

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