Diagnosing Dim Nav Lights
- Bad switch itself on nav light circuit, or bad lighting switch.
- Some other cross connect; on our boat the lights to the instruments are cross wired into the running lights, so when the running lights come on (via the running lights switch) the instrument backlighting comes on, neat idea, probably done everywhere elsewhere, but requires good wiring and understanding of both panel and instrument wiring requirements
- Leaking ground somewhere - try checking the wiring to and from with a digital meter for continuity
- Check the voltage at the running lights when they burn "weakly" and trace the wiring - could be something like the "other side of the coin" from David Aucella's recent answer to "no cabin lights" on a newly posted FAQ - could be that somewhere along the parallel route that the lighting ground wire takes all around the boat (like, 100 feet!!) there's a connection that shouldn't be there. Look for the blue triple connectors that "make" the branch circuits. There could be one there that's improperly connected to your nav lights. As Dave suggested, look up under the nav station storage compartment for the first of many of these big blue meanies.
- Stu Jackson, Aquavite #224, San Francisco
- The battery positives of the running and cabin lights are touching each other somewhere. The simplest and most obvious is to check the back of the main electrical panel for touching spade connectors. Every production year C34 electrical panel is a little different and in 1988 production Catalina stopped using fuses and went to circuit breakers. I'd attempt to trace both the cabin and the running light positive wires as far as I could. I wouldn't waste many, many hours or contact an electrician. What I would do is go ahead and re-wire the bow and the stern running lights with marine grade #16 gauge wire pair and use the old positive wire as a tracer to pull the new wire through. That way you know that you've got the most important circuit rewired properly. If you have a problem with the cabin lights, at least you've only got one circuit to chase down. Ron Hill, Apache #788