2005 Mazda6 stereo display short

Hello! I have been trying to find an answer specific to my issue and have yet to succeed. The display was basically only show in maybe 50% of the characters so I ordered a new one on Ebay. I watched a video online and I took it out then swapped the new one in. I did not disconnect the battery as I didn't think it was a big deal... now, neither display works at all, the new or the old (50%) working one. I have checked every fuse under the hood and in the kick panel. I have no answer. I have checked the connections and everything seems fine. There's 1 group of cables that connects from the stereo to the display and the sound that occurs from pushing a button on the display is heard but it shows nothing on it. Does anyone here have any ideas or any tips I can try?! It's a 2005 Mazda6, 5 door / hatchback and has the boss sound system

Thanks!