What was found
ON FLIGHT 4161 DURING THE CLIMB AT APPROXIMATELY 4000 FEET THE FIRST OFFICER REPORTED THAT THE PITCH TRIM SWITCH WAS STUCK IN THE UP POSITION. THE CAPTAIN’S SWITCH WAS WORKING OK AND OVERRODE THE FIRST OFFICERS SWITCH. THE CREW ELECTED TO RETURN TO ORD. THE AIRCRAFT LANDED WITHOUT INCIDENT. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED THE HORIZONTAL STABILIZER PITCH TRIM SWITCH IAW EMB AMM 27-40-03. THE OPERATIONAL CHECK WAS GOOD. NO DEFECTS NOTED. THE AIRCRAFT WAS RETURNED TO SERVICE.