What was found
AT 85 KTS, DURING TAKE OFF ROLL, HYD B ELEC PUMP LOW PRESSURE ECAM. B QTY BELOW RANGE AFTER REJECT. UPON RETURN TO GATE, PRESSURE NORMAL & QTY NORMAL SECOND REJECTED TAKE OFF IN 2 DAYS. ACCUMULATOR PRESSURE 700 PSI. PRESSUIZED HYD B SYS. ONLY GOT 700 PSI & FOUND HYD B SYS OVERSERVICED. PRESSUIZED HYD B SYS. ONLY GOT 100 PSI & HYD B PUMP MAKING NOISE. DRAINED HYD B SYS FLUID. FOUND HYD B ACCUMULATOR AT 550 PSI WITH TEMP 37 F. SERVICED HYD B ACCUMULATOR TO 1100 PSI. PRESSUIZED HYB B SYS & SLOWLY GOT UP TO 2900 PSI. TURNED OFF HYD B SYS & RE-PRESSUIZED HYB B SYS, GOT 100 PSI AGAIN. REPLACED ACCUMULATOR & NOW PRESSURE IS HOLDING. BLUE HYD SYS WITHIN LIMITS IAW AMM 29-12-00-710-001-A, NOW BTWN 2300-3000 PSI WHEN OPS FLT CONTROLS & AT 3000 PSI WHEN STEADY. PERFORMED IDLE RUN WITH NO DEFECTS NOTED. HYDS WITHIN LIMITS & NO MESSAGES.