No voltage on Ramps

Hi,

I just assembled the mechanical parts of Prusa i2 and am now struggling with the electronics. I am using Ramps 1.4 with Arduino Mega 2560. Arduino is working fine, but I am unable to get more than 1.3 V on stepper drivers. The voltage reamins the same regardless of whether the 12V power supply connected to Ramps board is switched on or off. This implies the 1.3v that I am getting on stepper drivers is coming from my laptop, and nothing from the power supply.

Can't understand why the 12V is not flowing down to the stepper drivers

Would highly appreciate your inputs.

Thanks,
Rohan

Edited 1 time(s). Last edit at 11/14/2014 03:06PM by ronnit2710.

first thing the 12v going into the ramps does is go threw a polyfuse the square yellow things. Check that 12v is getting past those.

There shouldn't be any voltage on the 12V rail if it isn't being fed from the power supply. You aren't measuring the voltage on the trimpot, are you?