As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING START, RIGHT ISOLATION VALVE DID NOT OPEN. TRANSFERRED TO MDDR 128880 AS PER MEL 36-11-06, CAT 'C'. DISP: GTC 09:27Z, ITEM M1: REMOVED AND REPLACED RIGHT ISO VALVE IAW AMM 36-11-04, OPS CHECK NORMAL. PLACARDS REMOVED. THIS CLEARS MDDR 128880.