[SOLVED]Ramps 1.4 connecting but unresponsive motors

As i wrote in the subject my ramps 1.4 is behaving strangely after a power on/off/on, i should mention that the printer worked totally fine, i just did a 20 hour print and some minor prints in the last days.
The board connect fine with the PC, i get the normal reads at the boot, i can load eproom value, the extruder/bed thermistors read the temperature and i can heat up both, i can power up the fans, i can't however move any motor, i can't home the printer or move the extruder motor (after heating up the extruder).
When i issue the home command from the lcd controller it freezes up and nothing happens, from repetier (PC) it does not freeze but nothing happens, i can issue other command but no one is executed and no command queue appears.
This is not my first printer and i'm quite experienced but my knowledge in electronics is not that good, i've done the obvious attempts, i've disconnected the power and the usb, restarted the PC (to reset any possible arduino connectivity problem), resetted both ramps and mega, flashed the my last rom and visually checked both mega and ramps board, there aren't any evident circuit problem but like i mentioned i'm not that good in this field, i have a tester but i don't really know what to test.

Obviusly i could just buy a new ramps and mega, the price from china is ridiculously low, or i could make the most of the situation and switch to a smoothieware board since i'm running a delta, still i'd have to wait some time and if possible i would prefer to avoid it.
So here i am, asking for help, anyone had a similar problem or have any idea what could have gone bad?
(Thanks in advance for any help you could give me)

Update: E motor started working again, moves in both direction and at various speed. i still cannot home the other axes therefore the only command i can issue is a move UP, when i do that the printer move DOWN and crashes into the plate, since we are talking of a delta this means XYZ stepper and motor works fine.
I am now thinking that the problem lies in the mega2560 since it appears as a bad logic to me, any idea?

Update: The problem was in the Eeprom, resetting it to stock worked, Thanks to o_lampe for suggesting it!

Edited 3 time(s). Last edit at 08/01/2016 02:12PM by Nova.

Did you check your endstops? Might be a stuck switch that keeps the motors from moving?

You could also check the voltage between Vmot/GND pins on the driver chips.

Quote
o_lampe
Did you check your endstops? Might be a stuck switch that keeps the motors from moving?

You could also check the voltage between Vmot/GND pins on the driver chips.

All endstops work fine (3 endstops and the probe), I'm going to check if the driver chips get any current asap!

Update: E motor started working again, moves in both direction and at various speed. i still cannot home the other axes therefore the only command i can issue is a move UP, when i do that the printer move DOWN and crashes into the plate, since we are talking of a delta this means XYZ stepper and motor works fine.
I am now thinking that the problem lies in the mega2560 since it appears as a bad logic to me, any idea?

@o_lampe, all stepper read 12v at Vmot/GND, obviusly since i now know they can move.

Edited 1 time(s). Last edit at 07/31/2016 04:15PM by Nova.

That leads me to the idea, you might have wrong EEprom Settings or the Eeprom chip died.

You wrote, you've flashed the latest Firmware to be sure, but did you send "M502" and "M500" afterwards to refresh the Eeprom?
Also try M503 to see, if anything is wrong with the Eeprom.

Quote
o_lampe
That leads me to the idea, you might have wrong EEprom Settings or the Eeprom chip died.

You wrote, you've flashed the latest Firmware to be sure, but did you send "M502" and "M500" afterwards to refresh the Eeprom?
Also try M503 to see, if anything is wrong with the Eeprom.

You my Friend are a lifesaver, resetting the Eeprom with M502 working perfectly! I I hadn't thought of doing that because I thought I had reverted to a firmware build with Eeprom disabled.....
It was two scary days, Thank you o_lampe

Edited 1 time(s). Last edit at 08/01/2016 08:39PM by Nova.