As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE CLIMBING OUT ON DEPARTURE CREW NOTICED BURNING ODOR, LOOKED BACK AND THE CABIN WAS FILLED WITH SMOKE. AFTER LANDING WE INSPECTED THE AFT EQUIPMENT BAY AND NOTICED A STRONG BURNING ODOR AND POTENTIALLY BURN MARKS ON THE ACM. ATC DECLARED EMERGENCY. REMOVED AND REPLACED THE ACM IAW AMM 21-52-13 OPS AND LEAK GOOD.