What was found
FLIGHT 3867, CREW REPORTED THAT ON CLIMB OUT, AND PASSING THROUGH 6000 FT WITH LANDING GEAR UP "BRAKE OVHT" WARNING MESSAGE POSTED. LEFT INBOARD TEMP INDICATED 14 OTHER TEMPS INDICATED 2-3. CREW RAN "BRAKE OVHT" ABNORMAL PROCEDURE LEFT INBOARD TEMP DECREASED RAPIDLY TO 2-3, ALL OTHER INDICATIONS NORMAL. DECLARED AN EMERGENCY & LANDED WITHOUT INCIDENT. ON LANDING ALL INDICATIONS NORMAL. AIRCRAFT REMOVED FROM SERVICE. MDC INDICATED LIB BRAKE T SENSOR OPEN/SHORT/OUT OF RANGE. REMOVED AND REPLACED THE NR 2 BRAKE TEMPERATURE SENSOR IAW AMM 32-46-01. OPS CHECKED GOOD. AIRCRAFT RETURNED TO SERVICE.