As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HEARD AND OBSERVED SPARKS & SMOKE COMING FROM THE SIDEWALL AREA, JUST AT THE BASE OF THE F/O CHART HOLDER. SHUT OFF WINDOW HEAT ON RT SIDE. SMOKE & SPARKS STOPPED. IAW WDM 30-41-12. FOUND SAFETY WIRE ARCING NEAR TERMINALS 1 AND 2 ON TB5038. REMOVED THE SAFETY WIRE AND INSPECTED TB5038. NO DAMAGE FOUND. WINDOW HEAT CHECKED GOOD IAW AMM 30-41.