As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(EMERGENCY DECLARED) CLIMBING THROUGH FL 270 WE RECEIVE HYD Y RESVR LO LVL ECAM. ECAM LED UT TO SHUTDOWN PUT PUMP AND ENG 2 PUMP / FOUND YELLOW HYD RSVR LOW LEVEL SWITCH WITH LOW VOLTAGE. REMOVED AND REPLACED LOW LEVEL SWITCH IAW TSM 29-13-00-810-801-A AND AMM 29-13-41-000-004-A AND 29-13-41-400-004-A OPS AND LEAK CHECK GOOD"