What was found
AIR TEMPERATURE INDICATION FOR CONT CAB SUPPLY DUCT IS INTERMITTENTLY INDICATING FULL HOT 100DEG C. DISPITE TURNING TEMP CONTROL TO FULL COLD. DUCTS ARE BLOWING FULL COLD DESPITE MAX TEMP INDICATION. TEMP WILL OCCASIONALLY SHOW COOLING AND THEN BOUNCE BACK TO FULL 100 DEG. C. GROUNDED - YES. ACCOMP INSP OF CONN. D3924 VERIFIED TIGHT. CLEANED ALL 3 CABIN TEMP SENSOR FILTERS. REPLACED TEMP INDICATOR WITH SERVICEABLE ONE. ACCOMP CABIN TEMP IND TEST, TEST PASS REF B737-900 AMM 21-61-32-400-801, 21-61-06-100-801 & WDM 21-61-51.