Hi, I've fitted a 40mm fan to my Prusa i2 X-carriage and wired it to my Melzi board's fan terminals but Gcode commands such as M106 S255 do nothing. I've tested the fan by wiring it directly to my PSU and it works just fine. I've also tried swapping the polarity which did nothing. Is there something in the firmware or elsewhere which needs configuring to enable fan control on the Melzi board?
Thanks