As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FOUND DURING PRE-FLIGHT - APU HOSE (FUEL FEED) WAS BURNED THROUGH THE PLASTIC SHIELD, AND THROUGH THE RUBBER INSULATION HALF WAY. CAUSE: LEFT ENGINE BLEED AIR AT MIXER VALVE IS BURNING THROUGH THE APU FUEL FEED LINE. NEED LINE ROUTED TO A DIFFERENT PATH.