As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE ADJUSTING PANEL AND INSTRUMENT LIGHTS BRIGHTER, A LARGE STREAM OF SMOKE CAME FROM THE AVIONICS CIRCUIT BREAKER PANEL AREA. SHUT OFF MASTER AND SMOKE STOPPED. FOUND 'PANEL LIGHT' CIRCUIT BREAKER TRIPPED, WAS THEN DETERMINED THAT IT WAS OKAY TO TURN MASTER ON. FOUND A FAILED LAMP AND ASSOCIATED CIRCUIT BOARD MELTED AND CHARRED, SLIGHT RESIDUE OF GYLCOL AND POSSIBLE WATER.