UPON RETURNING HOME AND PARKING MY VAN AFTER RUNNING AN ERRAND OF ABOUT 5 MILES, I SAW SMOKE COMING FROM THE ENGINE COMPARTMENT, RAN TO GET A FIRE EXTINGUISHER, THE FIRE WAS PUT OUT WITHIN 60 (SIXTY) SECONDS AFTER SEEING THE SMOKE. REMOVING THE AIR CLEANER AND OTHER COMPONENTS, -- THE WIRE HARNESS ON THE PASSENGER SIDE OF THE ENGINE COMPARTMENT WAS FOUND CHARRED BY THE FIRE. NO IMMEDIATE REASON WAS FOUND FOR THIS INCIDENT TO OCCUR.