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Cooling fan won't turn off...shuts down temp sensor and AC compressor

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8.4K views 2 replies 3 participants last post by  Jtoepf  
#1 ·
2015 SLE, 52k miles. Engine cooling fan comes on...loud...full blast and won't turn off. When this happens, coolant temp sensor stops working, and AC compressor also stops working. If I turn off the car, and restart...all is fine...until it happens again. Thoughts? (ps: even happend in early spring when it was 40 degrees out...but granted it was at idle. Now happens usually under load, and when idling)
 
#2 ·
Had a similar problem with my 2021 AT4.

Fan stayed on with the car off and almost drained the battery in a few minutes while I was trying to figure out what was happening.

Had to disconnect the power to the fan, temp gauge was bellow cold. Heater hose was hot.

Pulled code P0128, turned out to be the thermostat.