"they" means the indy shop who specialize in BMW repairs, they have all the eqp and SW to troubleshoot BMW. I have used them in the past and they were very reliable so far with their diagnosis with my other problems in last 4 yrs . They saw codes thrown from the solar sensor " I did not ask them what were the code # and they did not tell me either" . Indy shop think its due to solar sensor that aux fan keep running high. ( my personal logic is they are wrong and after reading everything about the solar sensor its hard to believe that can control the aux fan speed. I dont believe they will pay for the sensor if that didnt fix the issue, I did ask them and they told me they are very confident thats the issue. They asking me ~$400 for the complete job part + labor. Part is ~$212 plus tax from the Dealer rest is 1.5 hr labor and they will warranty the work. If i do myself I can get the same part for ~$150 from 2 Dealers in USA with no Tax. If its just popping the sensor out it wont take me more then 20 min to finish the job.

But I am still not convince this will fix the issue and so still reluctant to buy the part.
I was thinking to remove the sensor and see if fan stop running that might be a clue if sensor sending some wrong signal to the IHKA.

I agree dosent seems like solar sensor is causing it.. The SAV is running good, cooling is good, no lights for engine heating, not going in any limp mode, 40+ speed I dont hear the Fan and car runs very smooth with all its V8 power. It has 4 zone climate control system..