The fan of my Surface Pro 5 stopped a while ago. I noticed something was wrong when the machine became extremely sluggish every time there was a program using a lot of CPU.
Yesterday I received a replacement device and the fan stopped working right after installing the firmware update from the Windows Insider Release Preview (after I updated to v.1809).
This time I knew exactly what to look for, since last time I didn't make the connection between the firmware update and overheating issues I had from that point on.
Using the USB recovery image procedure to revert back to v.1803 did initially offer the older drivers and firmware updates through Windows Update, however the older firmware isn't installing over the (newer) beta firmware.
The firmware versions on a Surface with fan issues:
System UEFI: 234.2344.769
SAM Controller: 239.104.139
ISH Controller: 56.747.12
Intel Management Engine: 11.8.50.3448
Touch Firmware: 2.429.0.1.113.10
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