As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK, BURNING ODOR IN CABIN AND FLIGHT DECK. SLIGHT BURNING ODOR NOTICED IN CABIN AND FLIGHT DECK AFTER TAKEOFF. RETURNED TO PHOENIX. FOUND GASPER CIRCUIT BREAKER POPPED. REMOVED AND REPLACED GASPER FAN PER MM21-24-21. OPERATIONAL CHECKED GOOD.