What was found
CAPTAIN''S EFIS TUBES GO BLANK WHEN HYDRAULIC PUMP CYCLES. AIR TURNBACK TO SUX. MAINTENANCE REPLACED RT AND LT BATTERIES (P/N 4078-7), LT (S/N OFF F02021), (S/N ON B00680), RT (S/N OFF E02663), (S/N ON F00499). REPLACED PDU (P/N A2042C), (S/N ON CL-95661), (S/N OFF CH-12654). OPS CHECK GOOD.