As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
KDAY - FLT 13 - SMOKE IN THE COCKPIT UPON LANDING. UNABLE TO IDENTIFY SOURCE. SMOKE CLEARED QUICKLY ON TAXI IN. MAINTENANCE FOUND THE FIRST OFFICER'S HORIZON C/B OPEN AND THE FLIGHT DIRECTOR INOP. REMOVED AND REPLACED THE F/O'S INSTRUMENT AMPLIFIER AND HORIZON. NO DEFECTS NOTED ON GROUND CHECK. (M)