No stepper movement with MKS gen2 v1.2

Howdy folks!

Just finished setting up this i3 with my neighbor. The board is acting...strange.

With 12v verified to the board, you get zero status lights/behavior. No LCD, no nuthin'. If you plug in the USB side (to PC), the LCD will come alive and you will get status lights on the board itself. You can navigate through the options menu on the LCD, and you can connect to the unit (Repitier) and see indicator lights flash when you toggle settings.

However, the steppers fail to move. Any of them. From either software or LCD, same behavior. Voltage on the drivers all show ~0.8v.

Tested the actual stepper motors on my mega+ramps from other printer, and they move just fine. Also tested another set of NEMA motors on the MKS board just for grins, no joy.

Very weird issue. I first suspected garbage firmware, but the whole no-lights-on-12v makes me second guess it.

Thoughts?

So -- Firmware wise, she detects and responds like a champ. Did the marlin 1.1 upload again - no change, and no change for using the test cycle code (although I get lots of pretty blinking lights LOL).

I suspect that 12v for the motor side isn't making it to the steppers. I tested the drivers last night, but only tested the one side (logic side) but completely derped out and didn't test the motor side. Either way... I think this board is shot.

[forums.reprap.org]

Thought: Does this little sucker have serviceable fuses? Could have popped one side but not the other, since they're using a single 12v input for both 5a and 11a draw

Hi,

The MKS Gen is a great card. Probably one of the best Atmega 2560 money can buy.
Don't be that quick to bash it. Maybe the issue don't come from the board.
Of course there's electronic automatic fuses, hold on the reset button for a couple of seconds to unlock them.

Did you read my link ?

++JM

Edited 1 time(s). Last edit at 02/05/2016 03:18AM by J-Max.

I'm not bashing the board, but it doesn't work out of the box. I can repro the failure easily. Your link doesn't have any info on voltage or fuse issues...so what exaxly am I looking for in that thread? I didn't find any fuse reset procedures documented, holding reset doesn't change behavior.

Open to ideas, going to RMA thee board anyway so I have time to tinker