I changed out all my cabin lights for my 25.5 with the SS LED 4" Domes. Once installed, they all worked. On a separate trip, I switched on the starboard cabin light and it did not. I removed the unit and checked it out, works fine. Then I find the bathroom tube light does not work either, however the, Port, V-Berth and Rear Under Cockpit all work fine. They are all hooked up correctly. So I checked the connection at the panel and it is good. Dont understand it. Ed Godsey has the same boat, any help there Ed?
Robert,
In the off chance that my response may be useful to others I am responding to you in this thread rather than with a PM.
When I refurbished my 25.5 I reused the original wiring for the running lights and the inside (cabin) lights. And indeed I reused the original fixtures (both inside and out). I replaced the lens as required and also replaced the incandescent bulbs with LED “bulbs” from Dr. LED for the running lights and from SuperBrightLEDs.com for the interior lights. I also moved the two interior light fixtures in the main cabin (on the ceiling). I moved them forward as required so that the two forward opening port lights could be opened up against the ceiling. As originally placed the portlights hit the light fixtures first ... further minimizing clearance with the already low ceiling. While doing all of this juggling around I inspected (and disconnected/reconnected) each and every one of the original wires. The boat was NOT wired with multi-strand, tinned, copper wire as recommended by the current ABYC standards. But the wiring was done with what appears to be good quality, multi-strand, PVC insulated copper wire. Thus, unless the wiring has been stressed either electrically (short circuit, burned in two), mechanically (pulled in two or sheared in two), or chemically (corroded in two) ... it is very unlikely that the original wiring simple failed over time.
The most likely culprit is a connection at the end of a wire somewhere in the circuit. You mention that two light fixtures are non-functional: the fluorescent fixture above the sink in the head and the starboard fixture in the main cabin. I am reasonably certain that these are both on the same circuit (meaning they use the same +12VDC wire and the same return ground wire). You were less than clear on precisely what connections you checked ... or how you checked them ... so you may have already checked some of the things I am going to suggest.
Consider what you implied that you checked, I would say that the most likely culprit is the ground return from the starboard side inside lights. If I remember correctly, in my boat ALL of the ground turns (from everything in the boat) were all fasted together with an old fashioned, copper U-bolt w/ copper nut. And then one wire ran from this connection to the negative terminal of the battery. This rat’s nest was swing free behind the original switch/fuse panel that is on the bulkhead between the companionway itself and the ladder down into the cabin.
On my boat none of the ground wires were marked. This will make it very difficult to determine which ground wire is servicing the two starboard fixtures that are non-functional. But if you are confident that the switch/fuse panel and wiring is indeed delivering +12V to known good fixtures, then the problem has to be with the ground return.
To do any testing you are going to have to have clear access to the back of the switch/fuse panel AND to the point where all of the ground returns are fastened together. Thus before doing any testing with a meter, the first thing I would look for is a loose wire and/or evidence of a missing wire from the bundle of ground returns. If you find a loose wire you can use an ohm meter to see if indeed it is the ground return to the two non-Functional fixtures. If you find evidence of a wire missing from the bundle of ground returns then you need to poke around in the area behind the switch/fuse panel and find the wire itself. (This is where LED flashlights, LED headlamps and dental mirrors come in handy.) If you find a “loose” wire you can then use an ohm meter to determine if it is the ground return to the two non-Functional fixtures.
It is exceedingly unlikely that the ground return wire has somehow “gone bad” ... as in open circuit. It I most likely an open circuit on one end or the other ... and my guess it is somewhere behind the panel.
One last comment: I did have one the fuse holders in the original switch/fuse panel fail. The plastic simply cracked/failed from old age. This is an easy fix because the exact same fuse holder is still available. But since all of your interior lights are probably serviced (on the +12V side) by the same switch and the same fuse ... and since some of interior lights are still working ... it is unlikely that the fuse holder is your problem. I mention this only because I did have one fail ... even after carefully reworking the entire electrical system.
Hope this helps you find the problem on your boat.
Regards,
Ernest Godsey