What was found
DURING DESCENT, WINDSHIELD HEAT WAS SELECTED TO LOW, AFTER OPENING THE WINDSHIELD BLEED KNOBS. APPROX 1 MINUTE LATER AN ODOR WAS OBSERVED FOLLOWED BY THE -WINDSHIELD AIR OVERHEAT- ANNUNCIATOR. TURNED SYSTEM OFF, SMELL AND LIGHT WENT AWAY. RAN AC, RAN WINDSHIELD HEAT FOR SEVERAL MINUTES, OPERATIONAL CHECK OF WINDSHIELD BLEED AIR ANTI-ICE CHECKED GOOD. COULD NOT DUPLICATE ODOR OR -WINDSHIELD AIR OVERHEAT- ANNUNCIATOR. ALL WORK PERFORMED IAW CESSNA 560 ULTRA MM CH 30-41-00. NO OTHER DISCREPANCIES NOTED.