I fried a v3.0 board & bought a replacement that isn't acting right

[mr_fosi]

William! Where are you when I need you, buddy? :^D

So, I fried my A10's stock v3.0 board by shorting to the heater. Here's what I did after that:

- I bought a pack of new heater cartridges and installed one.
- I ordered a v3.1 board (and accompanying LCD) from Geeetech's store.
- I bought a set of new stepper drivers from Amazon.
- The board was out of stock, so I waited a month to get it.
- When it arrived today, I got everything plugged in and turned the machine on. There was a quiet snapping sound from the enclosure followed by the smell of burning electronics. The LCD screen turned on and displayed very strange characters, even for the Marlin boot screen.
- I turned the machine off and unplugged it then opened the enclosure to inspect the board.
- I flicked the power on for a split second and then off. Three lights lit on the board, so it's ok. <i>*WHEW*</i> However, a small amount of smoke emanated from from the Z stepper.
- I decided to pull the drivers back off the board. A sniff test indicated that all the chips except the one associated with the extruder were all fried.
- I turned the machine on without the drivers installed and the machine appeared to boot normally until I tried to navigate the menus. There was no response to the turning of the knob, though it would respond to the knob push-button.
- I found that when I had 1-3 of the drivers installed, the boot would initially look fine, then the display would start showing up the strange characters. The fewer drivers were installed, the long it took for the strange characters to show up.

So this is where I am. A nonfunctional printer, fried steppers, but a board that seems to be ok.

So what do I do now? I have the old drivers but I don't want to plug them in and fry them too (assuming they are functional).

I'm out of ideas.

PS: I have a video but I can't seem to attach it.

[William]

Hello, it may be that the drive direction is inserted reversely, causing the drive to burn out.
It is recommended that you recheck all connections and try again after replacing the good drive.
Here you can upload compressed files.

[mr_fosi]

I double-triple-checked that I installed the new drivers in the same orientation of the old ones.

Here is the link to my vid: https://www.youtube.com/watch?v=cTOilhIChX0

In the vid, I provide a clear view of the bottom of the driver with the pin labels. Could you tell me how I can ensure that my drivers are installed correctly?

Also, what about this weird LCD character behavior?

Thanks for your help as usual, William! :^D

[William]

Hi, the knob on the drive and the capacitor on the motherboard are in different directions, as shown in the figure:

微信图片_20200616092627.png (970.36 KiB) Viewed 7584 times

Are there three lights on after the main board is powered on? Can you provide a picture of the power supply?
Sorry i can't view your video.

[mr_fosi]

I see your orientation.

I think you're right: I had 3/4 in backward.

Regarding the motherboard lights, I get there lights like I stated in the OP. I'm pretty sure the board is ok.

The power supply hasn't been altered and is still set to the 110 V setting.

I'm going to try the old drivers in the proper orientation and see how it goes.

Thanks again for all your help. I'm glad that you are faithful to come here and answer questions.

[mr_fosi]

I got the old drivers in and no smoke!

However, the LCD still isn't responding when I turn the knob. It's also still doing the weird characters if I let it sit for a couple min.

What do you think?

I've got the LCD_2004_VC.

[mr_fosi]

See the photo

[mr_fosi]

So... I decided to hook the machine up to my Octopi to see if I could send it commands.

I discovered:

1) It took a loooong time to connect to the printer. Very odd.
2) Once connected, I could cause the Z-axis to home but I could not move it incrementally.
3) The X & Y-axes were unresponsive. I could move the Y-axis with no resistance and the X-axis felt frozen solid.
4) I was able to heat the hotend and the heated bed.
5) After turning the machine off, the X-axis would move freely.
6) I checked all the connections outside the board and the axes are all plugged in as are their stops.
7) The connections are the board are all solidly in place.
8) The strange characters from the above pic did not appear when the Octopi was connected though the knob still didn't work.

Could this be a driver issue (I'm using the old ones off the fried board)?

If not, what could it be?

[William]

Hi，once the driver is inserted reversely, it will be burned out, it is recommended that you replace the new driver

[mr_fosi]

Right. :^)

I've still got two new, unfried drivers.

What about the LCD and knob?