Laptop fan is off?

Following problem: The fan on my laptop (Fujitsu Lifebook A Series, Windows 7) is always just starting to spin, so when I turn on the laptop. As soon as Windows starts up (or shortly before), it stops cooling and does not start anymore. The laptop gets very hot but the fan does not turn on. What can I do?

Probably this is normal… Man would have to give a stronger load on CPU and GPU to see if then the fan turns on with increasing temperature… Maybe you can also adjust the fan curve in the BIOS

I opened and cleaned everything. The problem is still there. Have BIOS settings reset, not synonymous. But what I found out is that when I did BIOS update, the fan jumped suddenly. When the BIOS update was done, the fan went off again and does not start, even if the laptop is running downstairs very hot.