Posts made by lei261

Been using USB as 5V source, and printer has been printing for >20hrs without any issues. Thanks again for the advice.

@phaedrux @nightowl999
I initially had some errors reporting with 24V and 5V USB, that's why I wanted to look deeper and fix the problem.
Now I think about it, maybe I had some other loose wires, I will reconnect everything and try again.
Thank you again for the prompt reply!

@nightowl999
Haha, and yes, after seeing ur signature, I dug really deep in my junk box and did some quick testing xD. The statement itself has some truth in it, so i will shut up and listen

I'm going to try printing with 24V and 5V USB again, maybe the error was just onetime bad luck. But in an ideal world I'd like to fix the problem. I'm currently hesitant to solder an Ext5V onto the board, as I don't have a schematic. Not sure where to solder is the best way to go for a more permanent setup....

But you raised an interesting point regarding CNC, cuz I've been thinking about building a desktop CNC for a couple years. Current plan is to do it next year

@phaedrux
Was able to find some parts and wired up 5V and GND like below.

I was able to see 5V and 3.3V leds and the blue wifi led was also blinking. Is this how far I'd test it? Or should I do a print test with this setup? A little hesitant to do a print test because I have a "very temporary" setup.

@nightowl999
Hi nightowl, Thank you for the input.
I haven't thought of a good way of doing this at the moment due to limited wiring and soldering capabilities at this moment. Had to get ride of some stuff after I moved

Really not trying to disregard your input, can you pls explain the rationale?
I was able to measure 5V on the rail after I connected USB, on the output side of the inductor after the buck converter. I mean, if I solder a 5V PSU onto the 5V rail, I think I would get the same/similiar behavior as the USB, right?

@phaedrux Thanks for the input.
I looked around, I didn't really see any burn marks. There's only this buck converter that has something on it, a dent or scratch. I'm not sure if this qualifies for a visible damage.
After 5-10min of powering via 24V, I didn't feel anything hot with my finger, even the buck converter. I wish I had some of that "spray" thing that could immediately show you what gets hot...
I only have some 75% alcohol with me, and I'm not sure it's a good idea to spray that on the board. I've ordered some 91% IPA online, but will take some time to arrive.

I did some further measuring; if I connect the USB cable, I can measure 5V on the output side of the inductor. Since this IC doesn't have enable signal and most of the pins are connected to gnd, I'm suspecting it's the problem.
Edit: I just realized there's a DISABLE PIN, after setting Int5V jumper, I measured 0V on the Disable PIN.

Hi fellow 3D printing hobbyists,

I was finishing up my debugging and I accidentally shorted Fan0- and 5V with jumper wires.....See diagram below.

The fuses are electrically okay, and I didn't see any obvious damages on the fan mosfets.
Now when I power up the board (internal 5V mode), only Vin LED is on. No 5V/3.3V.
I'm able to turn on the machine using Ext 5V, meaning a USB for 5V/3.3V, and 24V PSU for other stuff. Ofc, the jumper is set to EXT 5V. However, it would print for 10min and report some extruder/heater error.

How can i diagnose the problem and to see which component is burnt?
I'm currently suspecting the A4403GEUTR, which is the buck converter next to the fan pins. I did some measurements around the IC. I got 24V on the input, but 0V on the output. Before I go ahead and order the IC, is there anything else I should look for? I hate to jump to a conclusion only to find out I've been chasing the wrong tail...

Thank you for any input !
Lei