Hello guys, I feel uncomfortable by asking (as per understanding) quite stupid question, the thing is that I bought Arduino MEGA from KeyStudio, now when I connect 2004 screen and switch Arduino on, I am getting messages "Testing 5.0V M Error" and "Testing 3.3V L Error". I attached screens with the error. Same happens when I connect Arduino with USB or 5V power supply which came with breadboard and same when I use 7,5V adapter...
I tried to figure out what the pro lem is by myself but I couldn't find any topics or information with same issue 
After I load sketch I don't see this message anymore, but I am not sure if problem does not exist anymore
Can you guys please help to figure out what is the problem?
That's not an Uno; please post a link to what you bought. It looks very much like a Mega. That however should not be the problem. Please post a link to the board that you bought,
Please post your code and the instructions that came with it. If the text did not change, upload might have failed.
The messages displayed on the LCD have nothing to do with the Arduino environment…
They are generated by the user program running on the Keyes board.
To understand why they’re being displayed, you need to know what that program expects.
By re—flashing the board with a new sketch, you have replaced the original ‘problem’ code with ‘your own’, hence the original program and it’s messages are ‘gone’.
Hi,
What control board did you set the IDE to, to upload your cvode?
Thanks.. Tom... 
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