As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RETURN TO FIELD DUE TO ALL HYDRAULIC QUANTITY INDICATIONS SHOWING ZERO. FOUND NO POWER AT 1834GQ IND RSVR HYD QTY AT REFILL BAY. CHECKED FOR 26VAC AT CIRCUIT BREAKER 1831GQ, NO POWER. FOUND CIRCUIT BREAKER 5XN1 BUS 1-131XP A SUPPLY POPPED ON 123VU. RESET BREAKER AND CYCLED POWER BETWEEN APU AND EXTERNAL POWER AND BREAKER REMAINED IN. HYD QTY PG CHECKED OK. REF WD 24-51-01 PG 1.