You can check these:
1.The motherboard 5V led work or not
If it work then it should be the LCD issue.
2.If the motherboard 5V led won't work
It means the motherboard has the issue.
I can't start printing!!
Re: I can't start printing!!
-Keep your mind and try to test it. 
-Everything will be fun！-Support all Getech printer.
-You can ask me the questions and I will kindly reply.
-Respect others is the best way you can get help!
-Everything will be fun！-Support all Getech printer.
-You can ask me the questions and I will kindly reply.
-Respect others is the best way you can get help!