Short Wire In Plug

A300-600 Right Outer Fuel Quantity Tank Spar Plug:

Quantity in cockpit inoperative. In-tank harness needlessly replaced over the weekend. I went straight to the aircraft side spar plug because 99.9% of the time...... that's where the problem is.

Removing the plug and looking for pushed back pins is the first step. Shit...... there's one not visible.

Time to gut all the orange tape and loosen up the back-shell. A slight pull on the questionable wire revealed......


This image shows the wire (in this case the Hi-Z signal wire) laying up against the wire bundle. It was "at least" 3/8 of an inch shorter than the rest. With it inserted fully in the plug, it would have a massive strain on it compared to the rest of the wires.

The only thing to do in this case is to use a environmental splice with a wire service loop to a new pin. One thing I checked for when inserting the pin was that the locking rings were still functional. If the pin would not hold...... it would require a new plug.

After our repair, the tank indication was normal.

Excellent find Mark! What is "...an environmental splice with a wire service loop...?"

rotate.aero/forum/wire-works/250-environmental-splices

A service loop is just an extra 3-4 inch section of wire looped around (like an oval) with the new pin and splice. There is no way to splice in a wire length to match the others. You'll just have the repaired one longer....... that's why you loop it around.

The only other option is to shorten and re-pin "every" other wire to match the length of the wire in question.

Now...... if you already have a few loops, maybe a complete re-do would be in order.