OK so it's not the power supply. I would open it up and see if anythings out of place connector wise and make sure the sled and transport look right. Once mine would not read anything, just four dashes on the display (I think). I just moved the laser back and forth a couple of times and it came back (knocking on wood now) That was a year ago. I'm sure you've unplugged it from AC for a few hours and then retried it right? Good luck.
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