As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON ARRIVAL AT GATE CREW REPORTED A PUNGENT ODOR IN COCKPIT AND CAPT HSI BRIGHTNESS FLUCTUATING. ON INSPECTION NOTICED SIMILAR ODOR FROM CAPT FWD CONSOLE AND E/E EXHAUST AREA. REPLACED CAPT HSI AND CONFIRMED COOLING FLOW GAINED ACCESS TO EQUIP. COOLING SUPPLY FAN FOUND INLET GRILL CLOGGED. CLEANED GRILL AND INSTALLED NEW SUPPLY FAN PER MM. RETURNED A/C TO NORMAL, NO ODORS IN COCKPIT, OK FOR SERVICE.