turn ff the printer and unplug from all power (mains and usb)
With a multi-meter check there is continuity from ramps gnd pins on power supply plugs to scard slot metal cover on the back of the lcd.
These should be connected.
if its not it is very likely you have the wrong lcd connector. There are two types.
With the foot down, you can either have the cable key on the left or the right
eg of left
eg of right
In this case you need to turn your cables around at one end.
The other option is you simply need to turn the contrast potentiometer on the back of the lcd to see the text (above sd card holder on image below)
Edited 2 time(s). Last edit at 04/26/2021 09:51AM by Dust.