What was found
PDX - FLIGHT 2462, DURING TAXI AND OVERSPEED GOVERNOR TEST, A WHITE MESSAGE AND YELLOW "ABORT" LETTERS APPEARED ON THE DISPLAY FOR NR 1 ENGINE. THIS WAS FOLLOWED BY A POWERPLANT MESSAGE. RETURNED TO THE GATE. MAINTENANCE CHECKED THE CDS SYSTEM AND FOUND A CODE 496. COMPLIED WITH THE OVERSPEED GOVERNOR TEST IAW TAKE 61-20-00-701-03. POWERPLANT MESSAGE WENT AWAY AND NO OTHER DEFECTS NOTED. AIRCRAFT RETURNED TO SERVICE. NO PARTS REPLACED.