As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TRANSPONDER WAS SMOKING AND SHOWED FAILED. VERIFIED AND CONFIRMED THAT THE ATC PANEL FAILED AND THE SMOKING WAS CONFINED TO THE PANEL ITSELF. VERIFIED NO ASSOCIATED CIRCUIT BREAKERS POPPED. WIRING AND ELCTRICAL CONNECTORS THE ATC PANEL VISUALLY INSPECTED AND FOUND TO BE OK. REMOVED AND REPLACED ATC/TCAS CONTROL PANEL, OPS CK' OK. A/C OK FOR FURTHER SERVICE.