Volt drop on starboard volt meter when the nav lights are turned on

[arcticspud]

Here is the background. Over the last couple of years, I have switched all my nav lights to LED nav lights. Not just the bulb. Each unit is specifically designed for this. If I recall, they are all Attwood units.

When I had just the bow lights and the "mast" lights as LEDs, everything was fine. The stern light was still the old incandescent light. When I switched the stern light to an LED, that is when the problem started.

The starboard volt meter shows a drop of about 1-2 volts when they are switched on now with normal being 14-14.5. I am curious why this would happen and how to fix it? Could a connection in the stern light be bad? :huh:

Thanks

 

[Lazy Daze]

Are you judging this by the gauge - or actually measuring right at the battery?

EDIT: Oh, pull the lightbulb out and try it again. Let's see if that really is what's causing the issue.

 

[arcticspud]

Are you judging this by the gauge - or actually measuring right at the battery?

EDIT: Oh, pull the lightbulb out and try it again. Let's see if that really is what's causing the issue.

I have to admit, I have only observed this from the gauge. I cannot pull the bulb as these are sealed units.

 

[Lazy Daze]

OK, then next step is get a cheap little voltmeter and put it right on the battery while someone flips the switch on and off.

If everything looks kosher there, then it's just simply a wiring/gauge issue. If you're still seeing that drop, then I would pull the fixture and repeat. The few minutes it will take to pull the fixture and then reseal is well worth the time to try and narrow down your search. You'll either find out that "yes, something is wrong with the fixture" or "no, the fixture is fine and the problem must be elsewhere". Either way, you're eliminating variables and this seems like a good place to start.