LED dash lights issue

Carmine

Old Man with a Hat
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I'm not really into the full LED conversions, so perhaps this is a known issue? I thought I would try a pair in my 69 Newport convertible because I knew I'd be driving late at night and I keep forgetting to fix the dash lights until I need them. Yes I'm sure I could have bought them cheaper online.

Anyways I picked up a set of the Sylvania blue lights at AutoZone. Wasted a whole bunch of time troubleshooting a blown fuse until the issue dawned on me. The OEM glass bulbs have contacts that fold in either direction against the glass envelope. For God knows what reason, the LED lights have contacts that wrap all the way around the bulb base. I can only assume there are models of the vehicles where the female end of the connector only has power on one side of the terminal, but that isn't the case on this design. ( I wish there were way too integrate photos into the text, so I'll just call this fig. 1)

Of course once you know there's power on both sides, you realize that inserting the bulb with contacts on both sides is essentially a dead short, blowing fuse immediately. Once you know the cause, the fix is simple enough.. simply Bend The Wire to contact only one side of the base, as on the OEM bulbs.

As for the lights themselves, a humongous Improvement although the dimming range is probably about 10% now, but I don't know who dims the incandescent bulbs anyways. At some point I will probably seek out some green ones, but it's low on my priority list.

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It looks like your replacement bulb is the Sylvania ZEVO super bright bulb, compatible with bulb types 194, 168 and 2825. Those retail here for $15 each (CAD).

I happened to have a spare 1967 Monaco instrument cluster handy, I pulled out one of the bulb sockets - here it is:
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The contacts are on the ends, not across the sides like yours. Strange.

These are known as Twist Lock Wedge bulb base for T10 / 501 / 168 / 194 bulbs.

And all the ones I see on-line have the contacts arranged side to side (ie left and right, not on the same side).
 
Sylvania is the WORST "brand name" light bulb maker bro. Check out Superbrightleds.com as an opener, though think twice and look thrice before you buy their wares. Some are excellent, others not. Once the weather cools down enough, I'm popping green LEDs into my '68 instrument cluster. I replaced the more specialized bulbs 3 yrs ago, to our joy, but didn't do the BA9 base panel bulbs themselves then. That's about the only Edisonian stuff left in the car, excepting only the headlamps, which I REFUSE TO REPLACE WITH DANGEROUSLY OVER-BRIGHT LEDS OR ANY EXOTIC HALIDES!!! I resent the **** out of bright headlights, and won't join in making things worse. But that's a different topic really.

There are hundreds of brands of Type 57 and for you, Type 158 LEDs out there. Remember that this modern stuff consists of Light Emitting DIODES, which only work one way, so polarity will be important. Forunately the Type 57 and other bayonet based lamps are usually made for negative ground, making things easy when those are the sort to replace. The 158s can aggravate one though. Test before insertion, always.

Light it up!
 
LED's are polarized. If you plug them in and they don't work, pull them out and reverse them.
 
But still everyone is missing the point - why are @Carmine 's bulb sockets strange? They don't seem to be correct.

At MoparFest I picked these up from a vendor (the outfit that refurbs instrument clusters and PC boards):

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Some are white, some are green. Going to experiment with the cluster backlight. $5 each.
 
LED's are polarized. If you plug them in and they don't work, pull them out and reverse them.

I've known that for a long time. Doesn't really have anything to do with my post. You can insert the bulb any way you wish, but if it contacts power and ground at the same time, it's not going to light up anything but the fuse. For a millisecond.
 
But still everyone is missing the point - why are @Carmine 's bulb sockets strange? They don't seem to be correct.

At MoparFest I picked these up from a vendor (the outfit that refurbs instrument clusters and PC boards):

View attachment 737226

Some are white, some are green. Going to experiment with the cluster backlight. $5 each.
Since you're getting the point, I'll include a bonus photo...

At the same time, this is one of the most unmolested cars I've ever owned. 69k miles when I bought it, original paint/top/seats. Not a single screw seemed out of place when I dropped the IP lenses. Factory wiring still in place.

I could picture connector designs where these Sylvania bulbs would never have an issue. And I could imagine bulbs where my (bad design) connector would work for 56 years, lol. But my connector + these bulbs? Zzzztt!

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Since you're getting the point, I'll include a bonus photo...

At the same time, this is one of the most unmolested cars I've ever owned. 69k miles when I bought it, original paint/top/seats. Not a single screw seemed out of place when I dropped the IP lenses. Factory wiring still in place.

I could picture connector designs where these Sylvania bulbs would never have an issue. And I could imagine bulbs where my (bad design) connector would work for 56 years, lol. But my connector + these bulbs? Zzzztt!

View attachment 737227

View attachment 737228
I think the big difference is that most of the dash lights just "screw" into the holes on a circuit board and get power from the face of the board.

What's different with yours is the socket is actually wired with both a negative and positive wire. That tells me it's most likely in an area that's not grounded. I don't know as I would call it a bad design, it's just a different design.

As you say, the conventional bulb that went in place 56 years ago would have worked well... The issue comes up with the LED replacement not being completely researched as to what it would fit. With all the junk I've bought over the years that was "supposed to fit", I'm not real surprised.

FWIW, I just changed the license light in my Ford Edge and it had that style bulb, but I replaced it with the cheaper (but still expensive) conventional bulb. I googled an image of the socket for laughs.

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Here's an inside look at the dark blue filter that surrounds the backlight in the '67 Monaco / Polara cluster:

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As dark as that is, I guess there is a blue hue to the light, to me it's not that much. Here's what the speedo looks like with a white LED bulb (the type shown above in post 5)

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And here's how that looks with a green LED (this is a green LED shining through the blue filter):

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The LED bulbs use 150 ma current at 12 volts (1.8 watts), the incandescent 158 or 194 bulb use 250 ma (3 watts).
 
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