As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE IN LEVEL CRUISE FLIGHT AT 29,000 FT THE (WING TANK O'FULL L-R) AMBER CAS MESSAGE ILLUMINATED. BOTH WING TANKS OBSERVED TO BE DUMPING FUEL FOR 2 MINUTES. - TROUBLESHOT AND FOUND BOTH WING VENT VALVES INOP. REMOVED AND REPLACED LEFT AND RIGHT WING VENT VALVES, OPS CHECK AND LEAK CHECK GOOD. WORK PERFORMED I.A.W. 750 M.M. CHAPTER 28-10-04.