What was found
SUPPLY DUCT GAUGE READS INTERMITTENTLY HIGH. CONT-50/AFT 55-70, FWD-40. ALL ARE INTERMITTENT. F/A'S REPORT TEMP A LITTLE COOL, BUT NO WAY TO TELL ON SUPPLY GAUGE. ACFT GROUNDED. SUPPLY DUCT TEMPERATURE GAUGE DOES NOT INDICATE CABIN TEMPERATURE. REF CABIN TEMP POSITIONS FOR ACTUAL CABIN TEMPERATURE INDICATIONS. RUNG WIRING FROM D90 CONNECTOR FROM PIN 3 TO GROUND ON ALL AIR TEMP SELECT SWITCH POSITIONS. CONTINUITY CHECK OK. INSPECTED CONNECTOR D11838 AT AFT TEMP SUPPLY BULB AND AT P5-17 D90 CONNECTOR FOR DAMAGE AND CONTACT SECURITY. NO DEFECTS NOTED. R & R CABIN TEMPERATURE PANEL, TEMPERATURE INDICATOR IAW AMM 21-61-32. OPS CHECK NORMAL. R & R AFT SUPPLY DUCT TEMPERATURE BULB IAW AMM 21-61-31. OPS CHECK NORMAL.