I am currently using an Elegoo mega2560 starter kit to make this and my LCD screen won't display anything. I use duino because my school Chromebook won't allow the actual Arduino software but I followed a guys tutorial on yt and now the screen won't display anything meaning The screen turns on but it won't do anything.Please Help!!
Im going to add a picture of my wiring in the comments.
Tutorial I followed: https://www.youtube.com/watch?v=nAv5pmGzqsk
Sorry the pictures are to dark to follow. You could post an annotated schematic showing exactly how you have wired it. If you do not feel like doing that right away adjust the contrast trim pot I did not see.
What exactly do you have hooked up to Vo (pin 3) on the LCD? Normally that's connected to the wiper of a 10K potentiometer hooked up to 5V and Ground. It almost looks like you have it hooked up to Vin on the Mega; yikes!
Do yourself a favor. Read and follow post #2 of the below link. Install the hd44780 library, restart your IDE and test your setup by trying the provided example.
You should have a 470 ohm resistor between V0 (LCD pin 3) and gnd.
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Contrast control is not the issue.
Look a the display in the photo in post #2,
You can see 1 row of blocks.
If contrast was an issue, you would either see no pixels at all or all pixels on.
In this case, the contrast seems just fine.
The most likely causes of an issue like this is wiring issues or connectivity issues:
- the pins defined in the constructor don't match the way the wires were connected to the LCD pins.
- the wires themselves have connectivity issues due to breaks or soldering issues.
Usually is it something quite simple like something overlooked or accidentally miswired.
--- bill
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Hi,
I would suggest you reverse engineer your project and post a copy of your circuit, a picture of a hand drawn circuit in jpg, png?
Hand drawn and photographed is perfectly acceptable.
Please include ALL hardware, power supplies, component names and pin labels.
Tom.... 
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