I have a problem in my ramps 1.4 My ramps board dont work when

I have a problem in my ramps 1.4

My ramps board dont work when I plug in with the power supply, but it works when I plug in with USB at the mega!

someone can help me??

I will also send some pictures to better view

It sounds like the voltage regulator of your arduino is dead!

@Antonio_beta @Nathan_Walkner if that? how do I confirm?

@Michal_Prokes yes I already confirmed and current flows

@Nathan_Walkner the picture that the LCD is turned off is power by ATX
and When is turned on is power by usb

@Nathan_Walkner no is not connect

@Nathan_Walkner I 12v in the polyfuse when it is connected by atx. and I have checked the diode and it passes current

I’ve been to check the voltage of the mega board and is 5v

@Michal_Prokes @Nathan_Walkner i tested the voltage Regulator of the mega connected by usb and I got 5v reading, when i tested be the 12v input and i dont have any type of reading in voltage regulator! It means it is even damaged??

The regulator must be fried. You can still use the mega and the RAMPS if you remove diode 1 by stepper 3 and then
if using an atx PSU run a 5V line to power the mega
or…
if using a 12V PSU, power the mega and RAMPS both at the same time with different supplies, whether one is usb, and the other is your main PSU. This should work fine.

@Michal_Prokes Thank you. I’ve completely confused with other dev boards.

@Aaron_Spaulding @Michal_Prokes

thanks for the explanation. I have one more question!
if I connect only ramps 1.4 my ATX is supposed to work? exprimentei is that it and the LED does not turn on

@Michal_Prokes Thank you for your help!!

the problem is solved, I changed the voltage regulator and is now working well!!
Thanks for help

@Pedro_Pinheiro Cooool