As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CONT CAB ZONE TEMP LIGHT ON EXTINGUISHES ON RECALL. GROUNDED - YES. REF B737-800 FIM 21-61 TASK 861. NO FAULTS ON #1 OR #2 PACK TEMP CONTROLLERS. OPERATED PACKS FOR 1 HR, NO ISSUES DETECTED. TEMP INCREASED AND DECREASED AS COMMANDED. TEMP FAN OPERATED NORMAL. CONTROL CABIN FILTER WAS DIRTY. CLEANED FILTER, SENSOR AND FAN. OPS TEST NORMAL.