Cabin Lights: Where to look if they don't work, tips on troubleshooting
Collated by Stu Jackson; contributors: Art Bayer, David Aucella, John Nixon, Gary Wiseman, and Jim Moe
Art's question started this dialog:
When I arrived at the boat 2 weekends ago I found that the cabin lights would not come on when I switched them on at the control panel. All other lights, instruments and appliances are working when their switches are switched on at the control panel. The fuse looked fine but I changed it anyway to no avail.
David replied: I think I've got it! Same thing happened to me a couple of years ago. Solution: check the snap connectors (they are a small blue connector that snaps together and pinches through the wire's cover insulation and connects the "hot line" to the line for the interior lighting). They are located in the cabinet above the chart table right at the headliner. Unsnap, clean and reattach.
John added: Another thing to check is the spade connectors on the back of the fuse/CB for the cabin lights. On HARD TIMES ( #1170) I had several instances of poor connections there. You might also want to verify that the ground wire for the lighting circuit is still OK: it will be one of the wires in the ground terminal strip back behind the circuit panel.
Gary suggested: I go into the back of my panel each spring and, as regular maintenance, check the spade connectors, etc. Over the years I've found several loose connections and initially some bad wire runs and "additions" by the previous owner. Losing lights is not the worst thing that could happen from interrupted power "in the dark of night". I'd hate to lose instruments, auto helm, or radio due to a loose connection. Its worth checking regularly. The same applies to the engine panel. It's in the same category as checking thru hulls, etc.
Jim contributed: I've read with interest some of the comments Art's question has inspired. The connections from the dark blue (hot) wire and the black (ground) wire coming from the panel to the same respective color wires in the run that goes around the boat near the hull-deck joint on my boat were not so great and had some voltage drop so I redid them. Also used an additional run of #14 wire across to the starboard side of the boat to reduce the voltage drop to the lights. Catalina's scheme of "daisy chaining" the cabin lights with #16 wire results in too much voltage drop and subsequent light dimming as more are turned on. Also, when I was making some additions to the electrical panel I noticed several very warm electrical connections to the flag and spade connectors as noted by John Nixon. I found that many of the crimped connections on the wires at the panel were done very poorly, apparently using a pair of pliers, and quite a few wires came out easily when I pulled on them. Though I am the second owner of the boat (a 1989) it appeared that this was a factory job as there was little evidence of added circuitry and all crimps were the same. I replaced all the questionable flag and spade terminals (we make these terminals and crimping tools for the railroad signal industry) and eliminated a lot of voltage drop at the panel.
At the time, I felt this had to be an isolated case, but now wonder if it is more endemic after reading some of the other comments. On the other hand, the panel on our C-30 which we bought new in 1988, was done very professionally.
I would suggest you check all the connections, both at the "T" connection above the panel and on the back of the panel. There are only a six screws to remove to take out the panel and its an easy task. However, be careful as the shore power connections on the back of the AC breakers are very exposed. Suggest you ALWAYS disconnect the shore power before removing and working on the panel.
Art concluded: Thanks to all for the advice on my cabin light problem. I was able to solve the problem. David Aucella hit the nail on the head. The problem was caused by two ground wires that were poorly connected by a clamp type connector which when closed, pierces one wire and connects it to the other wire which had been partially stripped to make a better connection. I've seen these type electrical connectors in cars and on trailers. As David mentioned, these particular connectors are in the uppermost shelf above the navigator's table.
In 1987, instead of running a ground wire to the ground gang strip behind the navigator area electrical panel, Catalina used these clamp quick connectors to connect the cabin light ground wire circuit which includes the bow running light to another ground circuit wire which runs to a grounding panel. There are at least 2 other connectors like this one in the same area. When I pried open the closest clamp connector of ground wires, which were under tension and obviously shorter than they should be, corrosion was evident. To fix the problem I had to cut the wires and then splice in extensions and then reconnect everything.