MacGregorSailors.com

I have a frustrating mystery on my hands and need your electrical/LED expertise!

I ordered these LEDs to replace my interior incandescent bulbs on my 09' 26m:

http://www.amazon.com/gp/product/B00EKK ... UTF8&psc=1 (White lights)

http://www.amazon.com/gp/product/B00IJI ... UTF8&psc=1 (Red lights)

Upon trying a single bulb of each type in my lamps, none worked. I had read on here that sometimes the polarity needs to be reversed with the LED bulbs. On my boat's lamps, the tip was positive and the base was negative. I have a main battery, leading to a circuit board, and on this circuit I have a stereo and the 4 interior lamps. So I switched each lamp's wiring attachment clamps from one to the other with the circuit off...after reversing them all, I turned on the circuit, checked to make sure the stereo still worked (unmodified) and then tried a different LED in each lamp...nothing. I then tried the incandescent bulb in each...they all worked. I then took a voltmeter to each lamp to ensure I hadn't made a mistake when I switched polarity (in case they were sequenced)...all of them now had the tip negative and the body positive (opposite original). The stereo never wavered in it's functionality with switches on/off or bulbs in/out.

So I think I have tried every possible electrical configuration and used different bulbs in every case (in case I blew one out) and I've tried all 6 bulbs at the end to detect just a bad bulb...nothing.

The only unknown at this point is that the packaging for the white bulbs says "GRV Ba15s 1156 1141 High...right Cool White Pack of 2 New"...and I don't know what the 'high' and 'right' refer to (car signals?)?

I'm perplexed...and yes...evidently, it does take this Floridian several hours to order and replace a light bulb!!

Please help if you have any thoughts and thank you in advance!

Weird...
What did the voltmeter say? If the voltage is above 13 V, that'll burn out the bulb, according to the specs. A well-charged battery can easily go above `13 V.
The bulb may not "sit" snugly in its socket. Has happened to me before with some LED's made in china.
I would try to attach one directly to the battery, by using two wires, just to make sure it works and the metal part is not coated in plastic or something...

March,

Thank you for your ideas...it is weird? The voltmeter was showing 12.4 volts in both pre/post modification. I also tried pushing the LEDs down further into the socket in case the pins were slightly different...nothing. Then a took a pencil eraser to the side and point of the LED connector to rub off any coating or buildup...nothing.

Odds of having 6 bad LEDs are pretty slim...but at this point, I'm wondering if it is something in the specs of these 2 bulb types??

Thanks again...keep the ideas coming...I'm perplexed!

Maybe the bulb doesn't reach all the way down to the base? If it's the "bayonet" type, pushing it all the way down won't do diddley. The little indentations on the side would prevent it from going all the way down.
That's why testing it with two wires would not be a waste of time

I'll have to check the bulb pin placement again, but I think they looked identical or at least not different in a meaningful way when I first checked them coming out of the package. This is an area to investigate though. Can you elaborate on the basic bayonet design and what happens as the center pin is depressed into the socket?

I noticed, when switching the polarity, that the pin was just attached to the wire within a spring housing to retain the bulb in place? I would think that any contact by the body of the bulb to the casing and by the pin end to the pin would complete the circuit?

That said, I will try to wire directly to the battery the bulbs...it would eliminate the obscure chance I have 6 bad bulbs. And I'll check pin locations again too.

In any case though...my incandescent bulbs are 1141's (stamped into casing) and the LED's are supposedly replacements (says 1141 in prior quoted description) and I understand Ba15s and 1156 are common replacement bulbs for 1141's correct??? Or are there finer points to the number differences?

Thanks for your help.

yes, I think "newton's method" might be useful here, . that is to say that you keep choping you problem in 1/2 until you find a solution.


I like the next step, could it be the bulbs?. Since your testing .. I would see if they work both way , or only one way. likely the "hot" end is the nub at the back ( most electical things are designed so that hte "hot stuff is the least exposed , hence the reason house plugs have the "hole" part, not the "prong" part.).

now, once you figure this out -- also reconcile this information with a multi meter, keep note of where the red, and black prongs are, and weather you get +12.5 volts or -12.5 volts. Then, you can ensure this same specification is happening at the other end. Once you have this information it might all became clear that the issue exists at the fixture itself, as has already been eluded to.

I wish to propose a slightly different issue you might have however. IF these 2 bulbs are linked in series, such that if one is on they are both on. AND the wire between them is revered. It will make it appear to be a dead circuit. when the bulbs are installed, Either bulb A, or Bulb B is backward, stoping the flow. When you reverse the wiring, what ever bulb was not working before, will now work, but the one that was working will now not and you still will not have a working system.


Kevin.

Did you reverse the polariy before trying the bulbs?
I don't know the bulbs but wouldn't the active terminal be positive or centre pin of the bulb?
You may have reversed the fittings for no reason

Allan

As suggested, simply it. Check bubs first. Then check fixtures for polarity and voltage. Then check for problems with contacts.
My guess is the bulbs aren't making contact with fixtures.

--Russ

"yes, I think "newton's method" might be useful here, . that is to say that you keep choping you problem in 1/2 until you find a solution."

That is until you realize that continuously halving something will ultimately go on to infinity.

I'd try the battery method as well. Don't think its the bulbs.

Definitely try directly testing with wires directly to the bulbs. I bought my LED bulbs twice - first from the low dollar Chinese importer and then from an established business like DrLED. I bought the second time since the first were so bad.

Ok...tested the bulbs on a battery...bulbs work...the tip is positive and the body negative (as original fixtures were wired and tested with no result?). They are identical in pin positions to the 1141 incandescents coming out and same diameter. I agree it must be the fixture, but all the measurements say it shouldn't be? Any thoughts on fixture modifications to create a better contact (foil wrap the body of the bulbto tighten contact?)?

I will try an eraser on the fixtures...maybe there is a film?

Thanks again!

Solder wires to the LED's to make them hard wired. Problem solved!

FYI you plant bulbs in the ground to have pretty flowers in the spring.

LOL

Thanks grady...I'm ready to bury these LED's!!

I thought about soldering them, but I want to be able to interchange white for red (for passages) though, so I'd prefer to not have to go that route...but then...I may never want to touch these LEDs again!

grady wrote:Solder wires to the LED's to make them hard wired. Problem solved!

As weird as this sounds, that's what I did. Contacts are a place for failure. Solder makes a solid bond that is corrosion resistant if not proof..
All my LEDs are soldered in for the most part. They last forever so permanent means 50 years + ....I'll be dead.


--Russ

Problem figured out.

When I thought I was reversing polarity originally, I was really only playing with the switch (other half of wiring was hidden behind the fixture whereas I thought the switch was playing with pos & neg). Once I pulled the circuit board and tested correct polarity there...and then pulled the stereo and traced correct polarity there...and then pulled the light fixture and traced the wires there...I found all the light sockets were wired with the hot lead to the casing vs the pin end (backwards to any conventional wiring I and some of you thought likely, but figured out by some of those reverse polarity gurus here...just not fully realized by me until tonight ) ...and, in addition, there were a mixed set of pin end configurations to the switches.

So...rather than rewire the circuit at the board and make it inconsistent with the rest of the board/electronics aboard (visually)...and rather than reverse the stereo polarity and risk a more expensive piece of equipment...I'm going to re-wire the light fixtures...truly reversing polarity (versus what I thought in the beginning).

Crazy. But I do now know my electronics/wiring configuration on board better!

Thank you all for your thoughts and ideas...any one of them could have been the answer!

I appreciate the resource this site is to me and I appreciate all of you...it's part of what owning a Mac makes it the best boat ever!

Fair winds!

PS...once I re-wired the fixture...those LEDs worked fine in case anyone else wants to mix red/white