I am testing Printrboard rev D with Merlin firmware installed on it.
The communication is fine except an extruder fan is not getting on. I tried using command M106 S255 but didn’t help.
The fan is working condition otherwise.
Can somebody advise me?
Thanks in advance!
You may have burned out the rectifier or otherwise have a bad one. I had a bad Printrboard in which the fan couldn’t be controlled - it was on 100% all the time. Replacing the board fixed the problem. Check whether you’re getting any voltage off the header pins. (Dumb question: you’re using the right header pins, right?)
The command was a bit hit and miss when I tried to use it so I set the initial state in code to on and left it at that. So the fan is on when the printer is on and change the speed if I need to there after.
You can find the initial setting at about line 199 in the Marlin firmware file Marlin_main.cpp.
At least if the fan turns on by default, you’ll not forget to turn it on like I often did and jammed the hot end.
Thanks Patrick and Mark!
I checked potential difference between pins on board and it was not 12 volts.
However, I reconnected the board 6th time and somehow it read ~ 12 V this time and the fan is working. Fan speed is changeable!
Now, I need to figure out whether it is due to just loose connection on board or something else.