I don't have any sealed beam headlights around to compare... Is the three prong connector on those the same dimensions as on the H4 (9003) bulb?
Thanks.
Thanks.
3-prong connector on H4 and sealed beams same?
- Thread starter BearZDefect
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Yes. However, on the old 165mm rectangular sealed beams, the pin out was different than on the H4 and 5.75" sealed beam. Same plug; different pin out.
Back when I got Cibie 165mm E-code replacements for the sealed beams in my 78 Olds, they actually came with an adapter cable that you plugged into the headlamp harness on the car and then plugged the other end into the H4 bulb base on the Cibie headlamp.
Thanks for your thorough reaponse, G-MAN.
I was concerned about the dimensional plug connection.
I was concerned about the dimensional plug connection.
No, they are different. The H-4 plug is like this |_| The sealed beam is like this \_/ When I installed H-4s, I broke the three prong plastic connector, separating the wires that already had crimped female blade terminals and plugged them into the male H-4 lamp terminals. If you do it this way you will need to identify the high/low/ground on the wires and lamp terminals.
Sorry, but you are wrong. There may be some sealed beam out there that has a plug like you describe, but if we're talking about std 7" round, 5.75" round, 165mm rectangular, and 200mm rectangular, then the plugs are identical. The pin out is different on the rectangular lights, but the plug itself is the same.
Try again G-Man. I bought these 165MM H-4s from Dan Stern for my Chevy S-10. The plugs on the stock sealed beam plugs do not fit the H-4s. Dan provided me conversion plugs that I did not use. I just plugged the female spades into the connector after I broke the DOT plugs.
You know, now that I think about it, you may be right. It's been almost 30 years since I put those Cibie lamps in my 78 Olds. My apologies.
I am right, however, when it comes to 5.75" and 7" round sealed beams. The plug and pin out for these is identical to that on the H4 bulb.
Edit: Wait a minute. If you have a S10 that uses a different sealed beam than my 78 Olds used. Maybe the plugs are different for those. Next time I go to the parts store I'll take a look at the 165mm sealed beams and see.
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Okay, I did a little online research and then rode up to Advance Auto (which is open 24/7 now) to look at some sealed beams.
The S10 uses the H4666 sealed beam, which is a 65w/55w hi-lo 165mm lamp developed strictly for use in two-headlamp applications. The standard 165mm sealed beam is the H4656, which is what came in my 78 Olds. The H4656 is 35w/35w hi-lo and was designed for use in four-headlamp applications.
The H4656 uses the exact same plug as the H4, only the pin out is different. (So I was right.)
The H4666 uses a modified plug where one of the pins is at an angle. This prevents this higher wattage sealed beam from being used in applications that call for the H4656. (So John was right also. We were just talking about two different 165mm headlamps.)
Here is an illustration of the two different pin types. The H4 and H4656 is on top; the H4666 is on the bottom. However, on the H4656 the ground and lo-beam pins are switched.
The S10 uses the H4666 sealed beam, which is a 65w/55w hi-lo 165mm lamp developed strictly for use in two-headlamp applications. The standard 165mm sealed beam is the H4656, which is what came in my 78 Olds. The H4656 is 35w/35w hi-lo and was designed for use in four-headlamp applications.
The H4656 uses the exact same plug as the H4, only the pin out is different. (So I was right.)
The H4666 uses a modified plug where one of the pins is at an angle. This prevents this higher wattage sealed beam from being used in applications that call for the H4656. (So John was right also. We were just talking about two different 165mm headlamps.)
Here is an illustration of the two different pin types. The H4 and H4656 is on top; the H4666 is on the bottom. However, on the H4656 the ground and lo-beam pins are switched.
I thought the sealed beams all had the same type plug whether they were round/square, large/small, etc. if they were Hi/Lo. I do not know if the High Beam only on the four headlamp setup is different like on your Olds. The S-10 uses only two lamps.
The only thing for certain is 165mm sealed beam Hi/Lo male spades are angled different than the H-4 male spades.
The only thing for certain is 165mm sealed beam Hi/Lo male spades are angled different than the H-4 male spades.
You're a tough nut to crack, aren't you? We're only talking about hi-lo lamps, so the hi-beams that were on my Olds are irrelevant. I just explained as plainly as I could that your S10 uses a H4666 165mm lamp, which has a unique plug. These lamps were developed for applications that would use TWO and only TWO 165mm lamps.
Four-lamp applications use the H4656 165mm lamp, which has the same plug as the H4 with a different pin out.
I went to Advance Auto and verified this with my own eyes.
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