LED replacement problems

[DBBRanger]

I just bought replacement LED's for the cabin ceiling lights in my R25 - 6 for the "cabin lights" and 2 for the "Dining/Galley" (Thanks to Rich on Roam for the eBay link!). However, of the 8 fixtures I'm working on, four do not work with the LED bulbs. That is, all 8 work with the standard G4 bulb, but when I replace them with LED's, only 4 work. I know the LED's are OK since I can swap them into a good fixture and they all work. It turns out the ones that don't work are the two "Dining/Galley" lights and the two "Cabin" lights that are the closest to them - but each pair is on a separate circuit. Has anyone had this problem? The best reason I can come up with is maybe Ranger combined the ground wires for those fixtures and only installed one ground wire back to the circuit breakers and thus the LED's don't like that. That's a stab in the dark (pardon the pun), but I know LED's being an active electrical element may be bothered by such. Anybody have a pay grade higher than mine that can suggest if that is a possible cause or have their own suggestions? I'm not looking forward to tracing down those wires!

Thanks

Doug

 

[Levitation]

The MarineBeam LED lamps are non polarized - you can plug them in any old way.
Other makes may be polarized.
So, the pins on the LED light either are not making contact in those 4 fixtures - or you have LED lamps that are polarity sensitive and 4 fixtures are wired backwards compared to the others

Push a short piece of solid strand wire into each contact on the lamp socket and use your VOM to measure the voltage across them and the polarity. If you have voltage then touch these wire stubs to the leads on the led light and it will light up. Try the polarity both ways on your LED lamp.
A side issue is that I have noticed that the square pins on the LED lamps are tough to get into the socket at times. I file an angle on the end of the pins before I insert them.

 

[DBBRanger]

- or you have LED lamps that are polarity sensitive and 4 fixtures are wired backwards compared to the others

That was it! They all work now.

Thanks

Doug