Wow, I didn't have to any fabrication. Took less than 3 hours from unpacking to all done. I don't see any need for an on/off/auto switch. If the fan is rated high enough, it just runs two to three shorts bursts in the hottest part of a Texas summer. The fan I have is rated for 600hp. The stock fan on the X5M runs much longer. Battery drain is not a problem on either one.

https://xoutpost.com/bmw-sav-forums/...ctric-fan.html

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X5 4.6 2002 Black Sap, Black interior. 2013 X5M Melbourne Red, Bamboo interior
Dallas