As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLIMBING OUT OF SEA, ECAM ALERT - "EXCESS CAB ALT". DONNED O2 MASKS AND TRIED TO TROUBLESHOOT PROBLEM. SWAPPED REGULATORS FOR PRESS. TRIED MANUALLY PRESS AIRPLANE. NO SUCCESS. RETURNED TO SEA FOR LANDING. UPON BLOCK-IN, COULD NOT TEST EITHER SYS 1 OR 2. FOUND #1 SYS BITE UNIT ROTARY SWITCH OUT OF "NORM FLT" POSITION. RESET TO NORMAL POSITION AND #1 UNIT TESTS OK PER A310 MM 21-31-00-5-01. OK FOR SERVICE.