According to RealOEM the X1 DOES have a solar sensor. Its the little plastic bit sticking up in the center of the dash. I've noticed that when on auto mode my X1 does a great job of varying the fan speed to compensate for outside temperature vs interior temperature as well as direct sunlight. My E38 740iL was the first car I owned that had this feature and it also worked well.
http://www.realoem.com/bmw/showparts...=64&fg=45&hl=1
And you can see it here on my dash:
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- Scott
Current Cars: 2019 X5 xDrive40i M-Sport, 2018 Camaro ZL1
Past BMWs: '16 528i, '00 M-Coupe, '14 X1 sDrive28i, '00 740iL, '02 325i, '99 M-Coupe, '00 323Ci, '79 323i, '83 320i