What was found
(CAN) ON APPROACH, 5 MIN BACK, TO LAND, CREW NOTICED SOME SPARKS AND SMOKE COMING FROM RT C/B PANEL. C/B FOR PANEL LIGHTING POPPED AND SPARKS QUIT. CREW LANDED ACFT, AFTER SHUTDOWN INVESTIGATED PROBLEM AND CALLED MAINTENANCE. AME REMOVED C/B PANEL AND FOUND THAT THE TOP SECTION OF THE PRINTED CIRCUIT FOR THE LIGHTING HAD ARCING DAMAGE. WIRING BOARD WAS REPLACED.