We recently had a A300-600 with a problem unnoticed by both the pilots and maintenance. 1/3 of the overhead cargo lights and all the courier lights did not work on ground service. Everything operated normal when the ship was on full power.
We tracked back from the cargo lights three-phase circuit breaker, one leg was dead. Power traveled through a couple relays and we had no power "in" on either one. We ended up in the power contactor area (power distribution) near the back of the E&E. After locating the feed contactor we found this.....
We installed a new terminal per Airbus procedures, but we noticed this.......
before we closed up........... Look at the upper right yellow terminal. A previous lug had broken off. This might be a growing issue on Airbus aircraft. This is not a high vibration area and all the wire bundles are securely tied down. These terminals should of been good for the life of the aircraft.
This problem was just dealing with interior lights. What if the busted lug was on a bigger contactor with flight safety items on the user end????
A300-600, ATA 33-30, Cargo Lighting