Printer dead after update?

i bought myself a vertex k8400 with two nozzles ,i started with one as re commanded a few adjustments en the first prints roll out so far so good .
now i want to update the firmware and did everything by the book but the last part i am not able to do because there is no more info on the little lcd screen.
i took out the shunt and and put on the power the nozzle heats up but no lcd screen ??
so can anyone tell me what went wrong? and better how to restore this problem.

i did all this action on a apple computer but used the right drivers and so on

is there anyone out there ho can and will help me with this issue

Ok he is alive again with the help of my reseller okaphone in groningen.
I used the wrong arduino i took the last update but i had to use 1.0.6 as in the text .
First prints are already made but need some adjustments the pla is not everywhere the same there are some week spot in the print i have figger this out.
If some one has an sugestion feel free to respond

There are a number of posts on the forum, from the more experienced users, describing more optimal settings for flow i[/i], temperature (190°C for most PLA colors), retraction distance (3 to 4 mm most commonly advised) & retraction speed (100 to 110 mm/s most commonly advised).

These settings are in the “Print” tab of the print configuration in the Vertex’s Repetier Host. You may want to save these settings under a new “Print” configuration name (make sure to then select this configuration in the slicer, afterwards).

I’d recommend looking the posts up: I’ve found their descriptions & explanations to be very helpful & these setting recommendations would most certainly influence your results in a positive manner.

Hope this helps?

Harry D.