What was found
AIRCRAFT WAS GROUNDED: PILOT REPROTS AC EXPERIENCED A LARGE CABIN TEMPERATURE OVERHEAT FOLLOWED BY A PACK FAILURE. WENT THROUGH THE QRH AND DETERMINED UNABLE TO PROCEED THROUGH MOUNTAINOUS TERRAIN. CREW CHANGED DESTINATION TO LAS AND THE FIRST OFFICER DECLARED AN EMERGENCY WITH ATC. MAINTENANCE CLEANED CABIN TEMP SENSOR FILTERS IAW AMM 21-61-06, PERFORMED BITE CHECK ON PACK TEMP CONTROLLER IAW AMM 21-51-00. OPS CHECK GOOD OF RH PACK IAW AMM 21-00-00. NO FAULTS AT THIS TIME.