Need more clues, the port side of my boat has seperate 12Volt runs to water pump, refer, macerator, cabin lites, shower sump pump and engine fuel pump.

Have you looked at the schematic in the owners manual either on board or here on our website?

Steve, I sent him over here from co.com, over there he was asking about lights.

Jake,
Catalina has always made improvements to their boats as problems or new ideas came up. What I am trying to say is that not all boats are exactly the same, even if they are the same model year. If it helps any, the electrical schematic for my '87 shows the cabin lighting wiring going forward along the hull on the stbd side, crossing over to the port side somewhere near the anchor locker, then heading aft along the port side. As Steve mentioned, other circuits followed different paths. As there is (normally) only one circuit for the cabin lights, I'd check the wiring at each light fixture. A faulty connection at any one of the lights might be a problem for the rest of the lights downstream of it. Sort of like Xmas tree lights. Also looks for frayed wiring and lose connections around the elec panel. Some of the wires might have been cut too short to reach the panel. Hope this helps.