Well you can just bypass it. It has 4 terminals 24v battery, 24v load, 12v battery, 12v load. It replaced the original polarity protection device and still has diodes between the battery and load terminals.
The LBCD added the function of monitoring the alternator output voltage and RPM to determine load and alternator status. It will disconnect the batteries by activating the disconnect relay over by the manual disconnect switch if it detects an overload condition. It will also light the charge trouble light in the dash if the alt does not achieve normal voltage over 1500 RPM. It added a capacitor bank to the normal polarity protection diode function to try and catch the massive voltage spike created when you disconnect a loaded alternator from its load(batteries). I have never seen a system used like this on any other vehicle I have ever worked on. I believe it was a band-aid to try and save the very expensive alternator from the grossly oversized battery bank…
If you are experiencing power interruption, it is just some diodes, are you sure it is not a corroded/bad connection at the LBCD? It is out in the weather and this is quite a common problem(have had one myself). I don’t seem to recall anyone actually having a diode go bad…
it has 6 main wires attached. Battery, alternator and cab cables for 24v and for 12V. The battery and alternator cables attach to the battery terminal for their respective voltage. If i recall 24v battery is on top, then 24 load, then 12v load then 12v battery at the bottom. there should be a placard/label on the side identifying terminals. The cab cables to the power panel connect to the load terminals For their respective voltage.
To bypass it place all 3 wires for a respective voltage(batt, alt and load) on a single terminal. Then disconnect the cannon plug which will keep it from activating the disconnect relay…
you can move that cable that was on the broken load stud and put it on its associated battery stud and you should be back operational…