Loud alarm and now the screen is blank

Hi there, first time poster but I read the forums time to time.

I bought a Makerfarm i3 Prusa, running RAMPS 1.4, three years ago and had it working well for some time. Then I moved to another state and brought my printer along, but on arrival I noticed the printer had stopped printing normally. The x-axis was drifting strangely towards home and it didnt seem like the z-axis was working either. Prints were coming out completely flattened and chaotic smears.

I assumed during the move maybe the x-axis had shifted quickly and applied some voltage to the board and fried something, although nothing appeared or smelled bad. Fast forward to just today, I hauled the printer out of my closet and decided to fix it somehow. I started by doing some basic travel tests, which went alright but not great, and then attempted a calibration test that failed horribly. The x and y axes stopped moving all together and the extruder went into overdrive so I shut it down.

Here is where it actually gets bad. I pulled off a few of the stepper drivers and had a look at the board, then plugged them back in, but the last board I accidentally placed in one pin lower than it was supposed to be. Powered it on, and heard a very loud alarm beep and the screen was lit up full. Turned it off, fixed the driver and rebooted to find the screen shows the regular homescreen briefly then goes blank.

I don't really have a clue where to start troubleshooting this board. Could somebody point me in the right direction of salvaging components off this board and fixing this issue? Also, please let me know what other information you need to figure out what the heck I've done to this poor machine.

Thanks

Edited 1 time(s). Last edit at 08/24/2017 04:16PM by Reyman.

pololu modules have both 12v and 5v on them. Plugging it in out buy one is very fatal for the electronics. Everything 12v touched that it shouldn't have is now dead


Consider the lesson learned and get new electrons. You can't repair the old and its not worth anyone's time or effort (including your own)

The ramps may be salvageable, but you will probably have to replace the mosfets, but is it worth it for $10-$15 saved vs hour of your time and the cost new mosfets?

Remove that last stepper driver and try the board again, if you are really lucky you may have only fried the stepper driver.