As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED A BURNING ODOR DURING FLIGHT. CREW RETURNED TO FIELD AND LANDED WITHOUT INCIDENT. MAINTENANCE ISOLATED THE BURNING ODOR TO COOLING PACK 1. MAINTENANCE COULD NOT DUPLICATE THE BURNING ODOR AND OPS CHECKED GOOD WITH NO FURTHER DEFECTS NOTED.