Ramps not powering with 12v only with 5v

Hello,

I recently bought myself a Ramps 1.4 with an arduino mega 2560 r3 rep but after installing the ramps and it components and running
it for like 5 hours it did shut down and now i cant get it running again with its 12v power supply only with the 5v power supply.

I am googling now for an hour and i just cant find the sollution..
I think its has something to do with D2 diode can anyone confirm this? or is it something else?

I hope someone can help me with it.

Greatings,
Darky112

Most likley the 5 volt regulator on the arduino has fried.

Hi,

Thats what i thought but it isn't.
These leds are on:
ON
RX
TX

[drive.google.com]
[drive.google.com]

And isn't reconised by my pc..
So i think my Mega 2560 is broken afterall...
is it fixable?

~Darky112

The mega has dual power supply for 5v

If its plugged into usb it will take 5v for there. Unless it has a better option
The dc jack and the Vin pin are a better option but go threw the on the mega voltage regualtor

To check the voltage regular you have to unplug USB and use the dc jack (or vin from a mega)


12 volts is feed into the mega vin line via d1 on the ramps (the diode under the polulu modules)

d2 is polarity protection, making sure you plug the power supply in the correct way

Okay i will try it at home, but why does my pc not see the arduino board? And why are led RX and TX on? It worked fine before for about 5 hours and now isn't doing anything... I did put marlin firmware on my arduino mega board so the board was connected before to my pc.. i juist dont know what o did wrong of do i have a faulty board or something? I hope someone can help me

Darky112

to many options... remove the ramps and power mega from a usb cable (this eliminates most possible external causes), can you still not see it? If not it is dead,


usb talks to the ATmega16U2 chip on the mega board. this acts as the usb/serial interface
or it could have a ch340 chip, does the same job.

Even if main chip was totally dead this chip would still identify the usb device to the pc.
Pc can't see anything but the usb/serial converter, talks threw it to the atmel2560 on rx0/tx0

I suspect its just a junk board from china that didn't last long.

These boards are also static sensitive... walking over a rug and touching the board could kill it.

Its not worth trying to fix, unless you do SMD repair daily and have the parts and expertise handy.

If your time is worth nothing to you, you could try re-flashing the ATmega16U2 with the usb/serial firmware.. you need a AVR programmer to do this (hardware)