We have a 1980's Globetrotter and the 12v lights were working fine. But now they keep blowing the fuse in the distribution panel, the sockets and pump work fine and fuses don't blow. As soon as you switch the lights on the little green light on panel briefly glows red then fuse blows. It has a brand new battery fitted.
The only thing I have done is taken the light down in bathroom to repair a section of the wall, do all the lights need to be fitted? Could it be this that has made fuse blow?
It sounds to me that the likeliest cause is that you've inadvertently caused a short circuit when you took the light fitting down. With the 12V disconnected check that the remaining cables are properly insulated from each other and no bare wires anywhere. Pay special attention to the area where you took the wall down - especially if the cable passes through it. If you've refitted the light fitting double check that you haven't accidentally switched the positive and negative connections as this would short the remaining lighting circuit directly to earth. Hope I'm not sounding too patronising but in my experience 99% of problems come from a very simple source. Always check the obvious first :D
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