Is my C3D LaserBoard a DOA?

Hi togehter,
I am still building my new laser cutter but I wanted to test my new ordered C3D LaserBoard.
Today I just connected it with the USB Cable and the PowerPlug to see if some magic happens. The only thing it did, was lighting up the VMOT LED (red).
I just checked one of the documentations and it said, that the 3v3 LED (green) should be on too… so is my board already broken before it did something?
Hope you can help on this… :frowning:


Can you show pics of the board, wiring, etc.?

I disconnected all cables and stuff and just plugged only the delivered power supply connector and the USB Plug.

Where’s the SD card?

wasnt in that picture… should i connect it now anyway?

Let it sit for a minute plugged in to see if the status LEDs begin flashing.

Without the SD in, the L1-L4 will not be blinking right away, but they should if you let the board sit on for 30 seconds - 1 minute.

Well - i unplugged it once more. And after I plug the power cable in its “sparkling” for a second. But no blinking on any of the LEDs.
The SD-Card is inserted but no L1-L4 is doing anything.
The board seems to be ok, nothing burned, or broken or something like that.
This is the first time i used it - and its not working at all.
Do I have to return it?

Hmm, these are tested before leaving the factory. I’m wondering if something else is amiss. Do you have a multimeter?

Yes I have one, but not here with me.
What do I have to test?

A sequence list to physically diagnose the board is currently being compiled by the developer and should be ready later. Don’t throw in the towel yet. When will you have access to the meter?

Tomorrow I have access to it (German Time).
Should I come back then, or do you send me some instruction.

I’ll check with the master engineer creator developer and see if the list is compiled by tomorrow my time. He has a lot going on behind the curtain, but is working on the list now. It is currently 16:36 on Sunday here.

So that means, the Board is not broken by now?

As soon as the list is compiled and you have your meter, we should be able to correctly diagnose the board to confirm if it is working correctly.

Hi Jamie,
here in Germany it is now 09:44 in the morning :smiley:
Just send me a message if you are Ready to go, then I will rush to my board and the meter and you give instructions, ok? :smiley:

? I need to go to bed now… I thought you send a quick response :frowning:

Thank you for your patience, I had to make the diagram and write the test instructions:

Please test voltages with the board powered on, and check continuity (if short exists) with the board powered off. Please have the SD Card remove from the board entirely.

In this diagram I show:

  • Ground (Gnd) with Black Square
  • VMOT Rail with Red Square
  • 5v with the Green Square. Touch it with the probe from the right so you do not touch any other pin, and be careful not to touch the SD card casing.
  • 3.3v with the Orange Squares - either on the SERIAL Header pin #2 from the left, or the head of the AMS1117 component - whichever you can access easier.

With the board powered on, and your multimeter in voltage measurement mode (mine has maximums of 2, 20, 200v and I choose the 200v mode for this) please place and keep the negative probe on Ground.

Place the positive probe on VMOT. You should see a steady 24v.
Place the positive probe on 5v. You should see a steady 5v.
Place the positive probe on 3.3v. You should see a steady 3.3v

For each of those, please tell me what happens.

Now, please power off and disconnect everything from the board.

Set the meter to continuity mode to check for shorts at the same 3 locations:

5v - GND
3.3v - GND

If there is a short between any of these 3 rails please let me know.

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Alright here we go.

Place the positive probe on VMOT. You should see a steady 24v. --> YES
Place the positive probe on 5v. --> NO I see 0.05v
Place the positive probe on 3.3v --> NO I see 0.02V

In continuity mode (I guess its the mode where my meter is doing sounds :smiley: )

Is it broken? :confused:

Please remove the jumper from the 5v Select Header (should be in the red position) and try to check continuity between 5v and Gnd again.

If there is still a short, please let me know.

If there is no short, move the the jumper over to the green position (right 2 pins).

Check for a 5v - Gnd short again now. Let me know.

If there is no short, plug in USB cable and see if any green lights turn on.

Also, if you put the SD Card into your computer, can see the config and firmware files on it?

I removed the jumper (completely) and there is still a short.
Should I test it anyway with the new green jumper position or is this obsolete?