A30 HotEnd Fan wiring?

[Sneakers]

Hi, I'm currently trying to replace the control board in my A30 printer with a new board from BIQU (SKR V1.1) and I'm a little confused by the wires that trace back to the control board from the PCB mounted on the Hotend. IF I'm reading the following diagram correctly, only the negative side of the Cooler Fan and Part fan can be traced back to the Control Board?

A30_Hotend.jpg (55.33 KiB) Viewed 8116 times

So if that's true, I've got a few questions.

1. Where are the fans receiving positive voltage from?
2. On the new control board (BIQU SKR V1.1), Do I only connect only the negative side of the fan?
3. If I only connect the negative lead to the new board, does this affect the PWM control of the fan?

[Macflame]

Did you ever get this sorted. I am in the same process of installing a SKR 1.1.
The motors and endstops were OK to sort and put new connectors on but the head extruder board has me scratching my head.
Plus I am unsure what wires go where from the filament detector.
I will have a little break on here and then see if I can fathom it out with your schematic.

[Sneakers]

Sorry, just now seeing this post. Did you still need help?

[Orion6909]

Hey there, when converting to skr 1.1 or 1.3 the 2 wires connected to the original control board are the negative leads one from each fan. So all you need to do is connect one to the negative fan pin on hot end fan connector, and the other to the fan 1 negative connector on the SKR board. No positive wires are necessary because the fans get their power from the small circuit board on the hot end. Hope this helps.