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Based on some reading I did on here, I went out and bought myself a 'Tail-light converter' like they use on trailers to allow a brake bulb to also flash for a signal. The problem is when I wire it all up, I can get the running lights to work (2nd bulb), but the brakes don't, signal or no signal.

My question is; the flasher has always been a bit touchy, where I would have to give it a knock once in a while to work. Could this flasher be causing the converter to not give me brake or signal lights? A faulty flasher cutting out your brake lights seems hazardous, but it's the only thing that I can think of.

Thanks!


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What are you actually trying to accomplish? Turn signals for your truck or wiring for a trailer? If it's for the truck, you are on the wrong path.


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'Bolter
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I still have the single rear brake light and two add-on signal lights. I bought new rear lights and would like to merge them both into the new units.


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If I remember correctly the purpose of the trailer converter is for when the tow vehicle has two seperate systems for stop lights and turn sigs (seperate bulbs). The box takes those signals and allows the single bulbed trailer light to flash when you have the brake lights activated. I suspect if you are trying to combine a two light set up into a single bulb light fixture you have something wired wrong. You say "second bulb" is there more than one bulb in the new fixtures? Kind of hard to help trouble shoot with out seeing and knowing exactly what you have and how you are trying to wire it.


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So the new lights have two single-filament bulbs. Large one supposed to be for brake/signal and small for tail lights. Tail lights work, but nothing comes through for the brake/signal which the converter is supposed to combine.


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Originally Posted by Goach2
I still have the single rear brake light and two add-on signal lights. I bought new rear lights and would like to merge them both into the new units.

I am ready to help, but want to be sure of these things,

1. How many lights on each side in the rear?
2. How many bulbs in each light?
3. How many filaments in each bulb?
4. What model turn signal switch do you have?
5. Is your truck 6V or 12V?

Does not matter which are original and which are new. That has me confused. I see Dave has the same difficulty as I do. Just need careful answers to 1, 2, 3, 4, 5
Pretty sure you DO NOT need the trailer converter at all.

We can talk about front turn lights after we get the rear straight. I'll be watching this post for your answer.


Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
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"Hey! I sound like Darth Vader!!
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You don't need a converter. You need the correct turn signal switch. Sounds like your current set up, the switch controlled only the add on turn signal lights. So you first need the correct turn signal switch if you don't already have that. Eventually, you will end up with some wiring going to the back that won't be used, depending on which wires you want to use to power your turn/stop lights.

Then it will be power to the brake light switch, then brake light switch to turn signal switch, then the magic happens in there and out to the four corners for your lights. When you draw it out on paper, it looks like a spider.

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1 - There are now two light housings on either side of the rear.
2 - Each housing has two single-filament bulbs in them.
3 - See above
4 - Flash-All 999 (4 wire)
5 - 6v

One thing that I read is that I should have gotten myself a powered converter. If I wire in an additional set of incandescent lights AHEAD of the converter, I start to see some action. This may be a step in the right direction, however if I can get around using the converter at all, them I'm up for that!


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Originally Posted by Goach2
1 - There are now two light housings on either side of the rear.
2 - Each housing has two single-filament bulbs in them.
3 - See above
4 - Flash-All 999 (4 wire)
5 - 6v

One thing that I read is that I should have gotten myself a powered converter. If I wire in an additional set of incandescent lights AHEAD of the converter, I start to see some action. This may be a step in the right direction, however if I can get around using the converter at all, them I'm up for that!


OK, but here is what you said just now.

Two housings on each side= 4 total housings

Each housing has Two bulbs= 8 total bulbs

Please try to be careful. I can't go forward with this kind of communication.

I guess we can make the 4 wire flash all 999 work, but it's really adding to a goofy way to go.

It's probably too late to return to normal, but would you consider one light housing on each side with one dual filament bulb in each and a 7 wire Signal Stat 900 switch?

It's also time to go 12V, you are improving your truck lighting and etc. This needs 12V for a lot of reasons. Easy to do. You are buying too many band aid gizmos to compensate for things. Let's slow down and back up a few steps.

Don't get discouraged or take offence, we are here to help.


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'Bolter
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Crap, sorry 'bout that, I'm Canadian eh?

One housing on each side, two single filament bulbs in each. I have a 90th birthday this weekend that I'm trying to get this done for, so ideally I would like to try and stick with the 4-wire, even though it's not optimal...


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TAKE OFF NEGATIVE BATTERY CABLE BEFORE WIRING

1. You need a 535 flasher for 6V
2. Wire the switch per the diagram.

Green wire is split to go to Left Front and Left Rear
Red wire is split to go to Right Front and Right Rear
Blue and yellow go to flasher P and L .
The other prong is X and is the "power in" prong. Wire from X thru a fuse and to ammeter.
The green and the red mentioned above, rear portion, goes to one of the bulbs in the two bulb housing. Green to left and red to right.
That's the turn wiring.

Brake wiring: One wire from brake switch goes back to rear and splits to left and right (other bulb in the housing)

Tail Lights: This is the problem with this set up of a 4 wire turn signal switch and the four single filament bulbs. You need another bulb or two for tail lights at night. The above will be OK for daylight. If you wire the tail lights to the brake bulb, nothing will change when you hit the brakes. If you wire tail light to the turn signal bulb, it won't flash when tail lights are on.
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flash all.gif (7.39 KB, 145 downloads)


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So, this is the signal setup that I originally had, with dedicated lights in the back. I can definitely put the signal to one bulb in the housing and brake to the other bulb, but this doesn't account for the tail lights. As I was thinking about it and some reading from the HAMB, these devices were originally setup to be placed after the vehicle's lights and before the trailer. Perhaps I just need to add in some additional bulbs before the converter, under the bed, then maybe it will work as it should?


1948 Chevy Thriftmaster 3/4-Ton
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Starting in the DITY
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I was still typing about tail lights. Read my post again. I don't have a solution for you on that. I'm not into where you are going. You need a 7 wire turn signal switch. Period. The reason for a 7 wire switch is that it shuts off the brake signal to the bulb/filament that needs to flash. That's what the other 3 wires do.


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'Bolter
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Gotcha, sorry for jumping the gun. Looks like day-time travel for now and I will test the inline bulb theory to see if it holds water. Signal on the brighter bulb? I worry about the brake light drowning out the signal. Will post back, thanks!

Last edited by Goach2; 05/21/2020 7:37 PM.

1948 Chevy Thriftmaster 3/4-Ton
Poncho "farming" in Ontario
Starting in the DITY
Continuing in the Project Journals
More images

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Sir Searchalot
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Who is turning 90?


Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
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'Bolter
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Great-Uncle Louie. I can't give him a ride at the moment, but I'll be driving by in something he would've driven back in the day.


1948 Chevy Thriftmaster 3/4-Ton
Poncho "farming" in Ontario
Starting in the DITY
Continuing in the Project Journals
More images

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Nice gesture.


Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn

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