As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE SMELLED A BURNING ODOR AND SLIGHT SMOKE IN COCKPIT WITH CABIN HEAT TURNED ON. OPENED COCKPIT VENTS AND SMOKE WENT AWAY, RETURNED TO CDB AIRPORT WHERE MAINTENANCE FOUND HYDRAULIC LINE FOR BRAKE RES. LEAKING ONTO HEAT DUCT, REPLACED LINE AND GROUND RUNUP NORMAL.