Cooling fan continuously running at high speed?

2011 MERCEDES BENZ S550
130,000 MILES • 5.5L • V8 • AUTOMATIC
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LEAHD54321
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  • 1 POST
Fan continuously running at high speed and takes a significant amount of time to turn off after the car is off. Ruined my battery
Apr 11, 2025 at 8:15 PM
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STRAILER
  • ✓ASE Certified Mechanic
  • 54,832 POSTS
  • ASE Certified Mechanic
Yes, this happens when the fan control module goes out or the engine coolant sensor goes out.do you have a check engine light on? If not, here is the location so you can change the control module out to fix the problem. You might want to do a CAN scan to help confirm the failure.

https://youtu.be/u-4syLc-ifQ

Check out the images (below). Let us know how it goes.

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Apr 13, 2025 at 11:10 AM
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