As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ETOPS SIGNIFICANT SYS - UNABLE TO REGULATE MID CABIN TEMPERTURE WITH AUTO CONTROL. FLUCTUATED ENTIRELY HOT THEN SMALL ADJUSTMENT CAUSES IT TO SWING EXTREMELY COLD. REQUIRES CONSTANT ADJUST AND STILL CAN NOT CONTROL. CLEANED MID CABIN TEMPERTURE SENSOR INLET SCREEN, PERFORMED ZONE TEMPERTURE CONTROL TEST IAW AMM 21-61-00, ITEM P OPS CHECKED GOOD. OK FOR SERVICE.