Replacement LED bulbs don't work

[liveaboard60]

My little 1988 Hunter 26.5 uses standard automotive 1141 12vdc light bulbs for cabin lighting.. While nice enough, I wanted to replace them with LED bulbs for 2 reasons. The power savings is the obvious choice, but also so heat the incandescent bulbs don't dry out and disintegrate the plastic cover.

A quick search on Amazon and in a day or two I have a bag full of replacement bulbs designed to replace the 1141 automotive bulb. However when I place the LED replacements they remain DED (Darkness Emitting Diodes) or in other words just don't light up.

Checking the voltage at the socket I see 11.63 vdc - ok, the battery is a little low because I forgot to turn it off and had left the radio on.. But when I tested the LED bulb directly on the battery (also putting out 11.63 vdc), it lit up like nobody's business..

So I am totally baffled why it doesn't work in the socket but does so when connected directly to the battery.. And yes I verified the socket does work (at least with the standard bulbs) and I tried the LED replacements on 2 different sockets.. Also the bulb does match the original bulb.

I am going to play with it some more this evening, but I wanted to see if anyone had similar problems.. flk k

[Sandero]

polarity?

[skipmac]

Originally Posted by Sandero

polarity?

That would be my guess. Test the voltage in the light and see which contact is the hot side and make sure the new LEDs are oriented correctly. The light fixture could easily be wired backwards. Doesn't matter with incandescent bulbs but LEDs care.

[liveaboard60]

When Sandero mentioned polarity, it set off a lightbulb in my head (sorry, I just couldn't pass up that opportunity)..

You know, one of those "Ah ha" moments..

But then I got to thinking, it isn't polarity because when I checked the voltage at the socket last night, I had the positive lead connected to the center contact on the socket and the negative lead on the housing.. And when I tested the bulb on the battery, I connected the center contact on the light bulb to the positive terminal on the battery.. Damn, and I thought for a moment that was the answer..

Good suggestion though.. Still worth double checking since it is possible (though not likely) I didn't see the little "-" (minus indicator) on the display.. I've been working with electronics for over 40 years, and I would like to think I would have seen the "-", but my main focus was on the voltage and holding everything in place so I could check it.. flk k

[skipmac]

Originally Posted by liveaboard60

When Sandero mentioned polarity, it set off a lightbulb in my head (sorry, I just couldn't pass up that opportunity)..

You know, one of those "Ah ha" moments..

But then I got to thinking, it isn't polarity because when I checked the voltage at the socket last night, I had the positive lead connected to the center contact on the socket and the negative lead on the housing.. And when I tested the bulb on the battery, I connected the center contact on the light bulb to the positive terminal on the battery.. Damn, and I thought for a moment that was the answer..

Good suggestion though.. Still worth double checking since it is possible (though not likely) I didn't see the little "-" (minus indicator) on the display.. I've been working with electronics for over 40 years, and I would like to think I would have seen the "-", but my main focus was on the voltage and holding everything in place so I could check it.. flk k

Yes, holding a meter in one hand, two leads in the other hand (like eating with chopsticks) and trying to read the display with one eye while watching the leads with the other eye and trying not to short something... easy to miss that little minus sign.

Have you tried just holding one of the LEDs loose and testing it with a couple of alligator clips to see if it works that way?

[SteveSails]

Do your lamps have a single or double contact on the base? The 1141 should be single contact but do the replacement bulbs match? If so maybe you missed the "-" on the meter display, easy enough to do.

[liveaboard60]

No the two lamps are the same in that they are both single contact in the center.

Well I went down to the boat this evening and put the meter back up to the socket and yep, the fool who wired the lamp fixtures wired them backwards.

At first I thought I may have been in luck since the negative side connected to a spade lug, but my hopes quickly faded when I noticed the positive side was soldered in place. Still I checked to make sure the LED bulbs would work if the fixture was correctly wired, and it did.

Now I get to re-connect 4 light fixtures. Thanks ya'll. flk k

[Sandero]

Maybe not... Perhaps the are on one wire run back to the batts and you can reverse the wires at the batts and do all the lights at once... Maybe.

[liveaboard60]

Originally Posted by Sandero

Maybe not... Perhaps the are on one wire run back to the batts and you can reverse the wires at the batts and do all the lights at once... Maybe.

Well the hot wire coming to the fixtures is a blue wire, with a black being the ground. I haven't traced back either wire at this point yet, but at the switch panel the wire coming off the hot side is blue as well..

I did think about switching it, but then the wire color designation would no longer follow code. And I am one of those fools who does things the hard way just to keep it all code compliant. OCD maybe, but also I don't plan on keeping the boat that long, and I sure don't want the next guy to be posting about the fool who took the lazy way out <grin>..

But at least I get to spend a couple of hours "piddling" on the boat..

flk k

[skipmac]

Originally Posted by liveaboard60

I did think about switching it, but then the wire color designation would no longer follow code. And I am one of those fools who does things the hard way just to keep it all code compliant. OCD maybe, but also I don't plan on keeping the boat that long, and I sure don't want the next guy to be posting about the fool who took the lazy way out <grin>..

Yes, take the short cut and the next owner of your boat will be on Cruisers Forum besmirching your good name to the world.

In my case I would keep the wire color code straight because six months from now when I had to do something else with the wiring I wouldn't remember I had switched the wires on the light circuit, short something out and set the boat on fire. Well maybe not set the boat on fire since I'm obsessive about fusing but I might melt some insulation.

[basssears]

Originally Posted by liveaboard60

Now I get to re-connect 4 light fixtures. Thanks ya'll. flk k

Some of the higher end LED bulbs are tolerant of reversed polarity where some cheaper ones aren't... you might be able to find some (more expensive) bulbs that would keep you from having to rewire.

[Ted and Relinda]

I had that problem and just pulled the fixture and swapped the wires. Works great now...

[Cadence]

Originally Posted by liveaboard60

When Sandero mentioned polarity, it set off a lightbulb in my head (sorry, I just couldn't pass up that opportunity)..

You know, one of those "Ah ha" moments..

But then I got to thinking, it isn't polarity because when I checked the voltage at the socket last night, I had the positive lead connected to the center contact on the socket and the negative lead on the housing.. And when I tested the bulb on the battery, I connected the center contact on the light bulb to the positive terminal on the battery.. Damn, and I thought for a moment that was the answer..

Good suggestion though.. Still worth double checking since it is possible (though not likely) I didn't see the little "-" (minus indicator) on the display.. I've been working with electronics for over 40 years, and I would like to think I would have seen the "-", but my main focus was on the voltage and holding everything in place so I could check it.. flk k

It may be far fetched? But from what you have said, I might look for a bit of corrosion in the sockets. The LEDs with there reduced draw my be more sensitive to some resistance?

[sailabroad]

The automotive LED bulbs have the negative (return path of the circuit) connected to the ground on the car - so the outside metal part of the 1141 bulbs are wired to negative, while one of the two( sometimes both - was there any burning smell?) pins will be the positive...while in your boat it will expect one of the contact pins to be positive and one negative.

Option (1) pull apart bulb and wire + and negative to each of the contact pins as it is wired in your boat. Inside the LED s there are often very short thin wires soldered to different parts of the bulb its not too difficult to replace these and wire them as for a boat.

Option(2) pull the negative wire from the socket for the bulb and attach it to the metal part that comes in contact with the "ground" part of the bulb= the silver metal outside part.( all the sockets on my boat have this metal bit that makes contact with what would normally be the bulb s ground but yours might not)

[Cadence]

Originally Posted by sailabroad

The automotive LED bulbs have the negative (return path of the circuit) connected to the ground on the car - so the outside metal part of the 1141 bulbs are wired to negative, while one of the two( sometimes both - was there any burning smell?) pins will be the positive...while in your boat it will expect one of the contact pins to be positive and one negative.

Option (1) pull apart bulb and wire + and negative to each of the contact pins as it is wired in your boat. Inside the LED s there are often very short thin wires soldered to different parts of the bulb its not too difficult to replace these and wire them as for a boat.

Option(2) pull the negative wire from the socket for the bulb and attach it to the metal part that comes in contact with the "ground" part of the bulb= the silver metal outside part.( all the sockets on my boat have this metal bit that makes contact with what would normally be the bulb s ground but yours might not)

Come on, it appears as though the OP knows what he is doing.