As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAKEOFF ROLL, RIGHT SEAT OCCUPANT NOTICED FIRE ON RIGHT FRONT FUSELAGE. TAKOFF WAS ABORTED. THE MECHANIC TROUBLESHOOTING THE PROBLEM DISCOVERED THE COMBUSTION HEATER AIR BLOWER WAS INOPERATIVE AND COMBUSTION AIR SWITCH WAS STUCK IN THE CLOSED POSITION. BOTH ITEMS WERE REMOVED AND REPLACED, AND AIRCRAFT OPS CHECKED GOOD.