Prusa i3 Hephestos LCD Screen doesn't work

Hello,

I have a Prusa i3 Hephestos and the LCD screen is not working (it turns on but it shows nothing). I have tried changing the LCD screen and other components like the Arduino and checking all the connections but the problem still persists.

Thank you

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.