As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) THE AUTO CABIN TEMPERATURE CONTROLLER FAILED, THIS WAS CONFIRMED TO BE A BURNED/DEFECTIVE CIRCUIT CARD INSIDE THE TEMP CONTROLLER. THE TEMP CONTROLLER IS EQUIPPED WITH A FAN AND DISTRIBUTED THE SMOKE FROM THE DEFECTIVE CIRCUIT CARD VERY QUICKLY. THE FLIGHT CREW DECLARED AN EMERGENCY DUE TO SMOKE IN THE COCKPIT FROM THE CABIN TEMP CONTROL UNIT.