hat brings me to how the governor controls the fans. I tested how well this works by placing the system probe between two ice cubes and keeping an eye on the fan. The monitor jumped down to 12 C, 4 C, 0 C then finally it settled on "LO". Apparently there are no negative readings. Checking the fan, it had completely turned off. The governor is doing its job. Removing the probe made the fan slowly start to spin again. It eventually got back to its normal speed and was working fine.