Input Voltage PWM fans not working
I had a controller fan cooling my stepper drivers which always worked fine, and since updasting to Ratos 2.1 Ive noticed it simply just doesn't turn on, even if in the Mainsail interface it says 100% when the steppers are engaged.
Ive added my printer.cfg and a picture of my setup. I have the fan on PD12 with a 12v jumper. My always on fans both work fine, I have J57 on a noctua cooling my pi, and I tested the fan Im using on my controller using that port and it spins fine. Also my 4028 is hooked up with PWM as per ratos guide and it works perfectly fine.
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Hm. Not sure how those ports work. I have my similar fan plugged in 4 slots above that, where you have something plugged in already. I'm also not using the pwm on it though, as it is quiet enough to always be running.
well theres a provision in ratos for a controller fan, which should turn on whenever the motors are engaged. I see when I home it goes to 100% for the controller fan but the fan itself isn't spinning, and no voltage is being measured across the pins.
Does it show up in the dashboard to manually control?
no manual control because I believe its either on or off, no actual PWM
reading klipper docs it looks like there is no manual control because it is a "controller_fan" as opposed to a "fan_generic"
But you're seeing the dashboard say it is trying to turn on and thats making sense so far. It just isn't getting voltage. hm.
and you don't have
pwm: true ...well it is a controller_fan, it should be on when the motors turn on, Its a simple 2 pin fan it doesnt have PWM really, its just a voltage thats on or off
for sure, I'm just reading through docs
Im not reading any voltage across any of the fan ports even if I turn "on" a fake fan I've created using a pin like PD13.
You said "no manual control because no pwm" but that isn't the reason. Was just chasing down that lead 🙂
you've got a F446 but thats the same pinout at least for that header as the 723 I was looking at at first
yeah 446
hmmmmm
I wonder could the mosfets be fried? Its weird its across every single fan except the always on ones
looking at the chips none of them look damaged, the board works totally fine
maybe? if you're good with the multimeter probes you could check for voltage change on the correct leg of the fet
yeah just wodnering which fet it is and where to check, Im thinking its these?
yeah, it'd be those. We have the schematic here https://github.com/bigtreetech/BIGTREETECH-OCTOPUS-V1.0/blob/master/Hardware/BIGTREETECH%20Octopus%20-%20SCH.pdf but not the gerbers so I'm not sure which leg of the fet it'd be
but its one of the two at the "top" in that image
would be Q9 for J52 PD12 fan Im looking at
either way the green LED is supposed to be on whe nthe fan is on, which is it not
yeah. And you've tested each of the fan outputs
yeah none of them seem to work
so either all of the fets are fried, or we've got something configured wrong :/
I gotta run and make some dinner, but good luck for now
would be wild if all the fets are friend, no clue how that could happen
huh I wonder if maybe theyre all donzo, my 4028 fan now has no PWM control, its either on or off now
so PA8 isnt working either
I think there must be something wrong, Im reading 20ish volts on some of my 5v rails
yikes
like my LED PB0 pin
and the 5V on J37
I think a regulator somewhere must be broken, but I cant pinpoint it 😦
time for a new control board I guess
Not the result we were hoping for 😞
That is what happened to me! exactly the same
It happened one day after working fine for a year, I cant remember the event that caused it, I update regularly but i doubt that could be the casue.
New MCU fixed all my problems.
20v on 5v rails
Wish we knew what triggered it but I'm glad the solution is "simple" if pricey
Its very strange, ive been browsing the forums and it would appear its happening more frequently as of recent. I doubt we are all making the mistake at the same time after the MCU´s working fine for a long time 🤷♂️
Could be as simple as having a 12V fan powered by 24V and it burns out the 24V supply to that section
If I had a bunch of dead boards, an oscilloscope, and a bunch of time I could figure out a common failure point but I have none of that lol