P1800 code on nissan quest 04 does not have power

Question

Have 04 nissan quest; getting P1800 code, cleaned terminal, checked hoses, tested valve, all is okay, power on hot side coming to valve, but no power or should I say, ground is dead. Where do I look for solution. Can it be bypassed or grounded elsewhere and still work? Car runs fine but once recently power steering had no power, fluid fine, then it in a few seconds to a minute, cleared up, did it once again for a minute but then fine again. Is it related? Wondering if the ground is shared somewhere.
Need to fix it so it can pass emissions or get a fine.