As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SMOKE STARTED COMING OUT OF THE CENTER OVERHEAD INSTRUMENT/SWITCH PANEL PRIOR TO TAKEOFF. IT WAS RAINING MODERATELY AND THE PIC WAS HOLDING THE WINDSHIELD WIPER SWITCH IN THE PARK POSITION. THIS CAUSES THE WIPERS TO MAKE A SWEEP ABOUT EVERY SECOND RATHER THAN A CONSTANT FAST ACTION. MAINTENANCE REPLACED THE WINDSHIELD WIPER SWITCH. AIRCRAFT WAS RETURNED TO SERVICE.