ODI became aware of a fire involving a Washington Metro Area Transit Authority (WMATA) bus.A WMATA contracted vehicle inspection identified the failure of a tapped hydraulic fitting to have caused the fire. Orion VI buses were built from 1994 to 2002.This investigation is specific to 1995, 1997-2000 production.Daimler Bus informed ODI that 1994 & 1996 model year buses were either prototypes or sold only in Canada; buses built after 2000 had a tee fitting in lieu of the tapped fitting in question.On October 20, 2010 Daimler Bus informed ODI that an internal meeting was planned to discuss the same concern as the one that prompted this investigation.ODI agreed to delay formally requesting information; an IR letter was to be mailed on November 9, 2010 if needed. On November 2, 2010 ODI received a 573 Defect Report (Recall 10V-538) that addresses the concerns of this investigation.This investigation will be closed.There is no associated IR letter.A copy of the defect report is attached.