Ultimaker 2+ heatbreak fan not working

Hello, I recently installed klipper on my old Ultimaker2+. At first all seemed to work fine but then I noticed that heatbreak fan is not spinning. Even when i preheated the nozzle to 200c.
Based on this UMO / UMO+ Firmware - Page 8 - 3D Printing Forum it seems like Ultimaker doesn’t have pin assigned to the heatbreak fan connector (j34) and have to be set up in firmware.
Do you think this could be in deed firmware issue or something else?

Thanks.

In the end i figured it out. Heatbreak fan is connected to pin PJ6