Rad error code 24 and 30

[crustycrabber]

I own two large frame rad electrics with the big tires. One of them started flashing 24 or 30 error code so I switched out the LCD screen in the power switch from the good bike and put it on the one that is acting up and it still reads that. Anybody else got any more guesses. I did open the plug underneath the pedals and make sure it was clean and not moist.
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