Blank MD4 SCreen at start-up

Jean-Marc Zanni 5 years ago in Master modules / MD4 updated by Gustav Widén (System support) 5 years ago 1

I am using an MD4-7 screen on a test bench. 3 out of 4 starts I get either a White Screen or a black screens with some colored dots. Once I saw what seemed to be blocks of black and white.

Looks like the video driver is not starting properly. The application appear to be running since the canbus messages are being generated.

Can this be caused by the regulated switching power supply during start-up or do I have a defective MD4 screen?

Thanks for your inputs.

For older MD4 units, it is possible to get a similar symptom if you ramp up the supply voltage slowly. Perhaps taht could be the issue? There was a hardware update to make it more robust against this situation: