What was found
THE CREW RECEIVED EICAS MESSAGES, NOSE GEAR AIR GRND, RT PROBE HEAT, ANTI-SKID, RECIRC FANS AND HYD PUMPS AND EMERGENCY LIGHTS ILLUMINATED IN FLIGHT. THE AIRCRAFT WAS RETURNED TO IAH WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND RT DC BUS SEC 1 C/B TRIPPED. THE CIRCUIT BREAKER WAS RESET AND ALL SYSTEMS CHECKED NORMAL. THE BUS POWER CONTROL UNIT WAS REPLACED. BITE CHECK SHOWED RT GCU SERIAL LINK FAULT. THE RIGHT GCU WAS REPLACED, AN ENGINE RUN WAS ACCOMPLISHED AND ALL SYSTEMS CHECKED NORMAL.