As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
POWER AND GROUND WIRES ROUTED TO APU STARTER THROUGH FIRE WALL WERE ROUTED 180 DEGREES OUT OF SEQUENCE AND SUBSEQUENTLY CONNECTED TO WRONG SIDE OF APU STARTER. THIS CONDITION EXISTED FROM THE MANUFACTURER. ADDITIONAL WIRE MARKINGS DESIGNATING GROUND AND POWER CABLES SHOULD BE UTILIZED.