My Ender 5 pro has the parts cooling fan go on when the printer is turned on and stays on until the printer is turned off. The heat sink fan is controlled by the G code as well as the control box. It's like the fans are switched. They are connected to the proper spots on the control board and would be hard to mix up since they have different connection methods. The printer has a 4.2.7 board and the firmware was downloaded from the creality site and it's the correct one for a BL Touch. I have changed the 4.2.7 board with another 4.2.7 and have redownloaded the firmware many times and still have the same problem. Does anyone have any idea as to what would be causing this? I have been using it this way for a long time and doesn't seem to be causing any issues with my prints but it absolutely drives me nuts. Unfortunately I didn't notice if this issue was present with the stock board in place before I upgraded and added the BL Touch.