As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SMELLED SOMETHING BURNING. APU GEN DROPPED OFF LINE. APU SHUT ITSELF DOWN. REPLACED APU CURRENT SENSOR RELAY (FOUND MELTED). FOUND WIRES AT APU STARTER GENERATOR TERMINAL BOARD MELTED. REPLACED APU STARTER GEN WITH SERVICEABLE STARTER GENERATOR. REMOVED DAMAGED TERMINALS AND TRIMMED OFF DAMAGED WIRE ENDS. SWEDGED ON NEW TERMINALS AS REQUIRED. PERFORMED OPS CHECK OF APU STARTER/GEN. OPS CHECK GOOD.