If the code (as Lippert stated) is generated by current drawn by the pump motor then go thru your pump motor's wiring and clean/tighten all the connections. A bad connection can cause low voltage and as the voltage goes down the current draw goes up. Voltage drop can also be caused by a bad 50a breaker.
Hint: The usual suspect is the battery's ground connections. followed by the breaker.
Clif & Millie
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