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I am looking up the 30 error that is displaying on your Precor 556 V1 Elliptical. Please wait a few minutes until I post again...
That is an error that indicates a problem with, or between, two circuit boards. Specifically, it is often caused by a loose cable between the upper and the lower circuit boards.
Or by updating only one of those two boards, but not the other (If you have run no updates on either board, then you probably don't have this problem.)
Or, if the problem has always been present, it means both boards are the wrong revision level to work with each other (which I presume is not the case.)
Or, one of the two boards could be electronically 'broken'.
Let me know the immediately preceding history and behavior of the Precor elliptical in question, and I will interpret the error 30 further.