What was found
DFW - FLT NR 3596 - SMOKE IN COCKPIT AND CABIN, AIRCRAFT EMERGENCY EVACUATION. 1B MULTI FUNCTION COMPUTER FAULTED AND WOULD NOT RESET. GROUND RAN AIRCRAFT FOR 10 MINUTES, FOUND NO SMOKE IN COCKPIT OR CABIN, 1B MULTI FUNCTION COMPUTER DID NOT FAULT. AFTER RESET NO DEFECTS NOTED, AFTER FURTHER TROUBLESHOOTING RAI P2.5/P3 SWITCHING VALVE INNER HOUSING AND PISTON RING. GROUND RAN AIRCRAFT AND WITH NO DEFECTS NOTED AND AIRCRAFT WAS RETURNED TO SERVICE. (M)