BY LETTER DATED APRIL 29, 2005, GM NOTIFIED THE AGENCY THAT IT IS CONDUCTING ASAFETY RECALL ( NHTSA RECALL NO. 05V198 ) INVOLVING CERTAIN MODEL YEARS (MY) 2003-2004 ISUZU ASCENDER, CHEVROLET TRAILBLAZER, GMC ENVOY, OLDSMOBILE BRAVADA AND MY 2004 BUICK RAINER VEHICLES.THE RECALL APPLIES TO VEHICLES BUILT FROM APRIL 2003 THROUGH NOVEMBER 2003 FOR A TOTAL VEHICLE POPULATION OF 286,478.GM REPORTS THE DIRECTIONAL/HAZARD SIGNALS FAILURE IS DUE TO STICKING CONTACTS ON ROUTING RELAYS IN THE FLASHER MODULE.GM WILL REPLACE THE FLASHER MODULE ON ALL INVOLVED VEHICLES.BASED ON GM'S SAFETY RECALL ACTION, THIS INVESTIGATION IS CLOSED.