5-wire tail-lights (for temporary mount) not plug-n-play

[achop]

Question:
I bought two LED taillights specifically because they include a Reverse/Backup Light function:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I want to use these as temporary-mount lights, when my hitch-mounted bike rack (loaded) obscures my Ford E350 van taillights.

Each light has a 5-wire pigtail, a few inches long where BLACK - Negative, RED - Brake Light, GREEN - Taillight, YELLOW - Indicator, WHITE - Reversing, with butt-ends on the 5 wires.

I was planning to use/customize a 5-flat trailer-side wishbone wiring kit (e.g., part # A25W5B) to wire up the taillights. I’d then use any 7-pole to 5-flat adapter to connect with my 7-pole vehicle outlet.

Main challenge: Most “wishbone” flat-wire trailer kits only send two wires in each “taillight bundle” [e.g., One tail light wire (brown) is bundled with left turn and brake wire (yellow), and one is bundled with right turn and brake wire (green)]. If I use this sort of 5-flat trailer wishbone kit:

1. Do I mate the appropriate functions from light to wishbone-bundle by splicing together, e.g. for the left light:
- Yellow (left turn/brake) from the wishbone bundle, spliced with …
- Yellow (indicator) and Red (Brake) from light pigtail?
What would be the best waterproof way to splice this? Can I connect all three wire ends in one spot?

2. Do I splice a second blue wire into the trailer side 5-flat connector, to create a blue wire “wishbone” (like the brown wire / taillight wishbone) to connect to the White (Reverse) wire on each taillight? (Why don’t any 5-flat trailer wiring kits make it easy to set up the blue-wishbone option for reverse lights?)

3. Would it be easier to just run a full 5-way flat wire out to each light, since the Light’s ground/negative wire also needs to go somewhere? Can I make the lights a little more “plug and play” with typical wishbone wiring by putting a connector of some kind on the 5-strand light pigtail?

4. Would it make more sense to install a 7-pole trailer-side wiring kit, in terms of fewer components/splicing/tweaks? Wouldn’t I have the same wish boning challenges?

5. Can I just crimp butt-end connectors and tape to splice, or should I solder these connections? This has to work for 2-3 weeks, but I could do a more permanent job later if they prove not waterproof enough.

Thanks for any tips!

[MadScience]

The separate turn signals aren't part of most trailer wiring. I'd just ignore the yellow bulbs on that setup and wire it like a normal trailer and then plug into the trailer plug.

Crimp, don't solder. It'll hold up better despite vibration. I've had very few problems with automotive wiring since I picked up some ratcheting crimps.

[achop]

Originally Posted by MadScience

Crimp, don't solder. It'll hold up better despite vibration. I've had very few problems with automotive wiring since I picked up some ratcheting crimps.

Ok, so i just looked up ratcheting crimp ... looks good.

[MadScience]

Looks like you edited, yeah ratcheting crimps are much more reliable. Normal ones work as well, particularly if you inspect the crimp carefully. However, it's not like ratcheting ones break the bank anymore.

[FXRQ]

Originally Posted by achop

Question:
I bought two LED taillights specifically because they include a Reverse/Backup Light function:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I want to use these as temporary-mount lights, when my hitch-mounted bike rack (loaded) obscures my Ford E350 van taillights.

Each light has a 5-wire pigtail, a few inches long where BLACK - Negative, RED - Brake Light, GREEN - Taillight, YELLOW - Indicator, WHITE - Reversing, with butt-ends on the 5 wires.

I was planning to use/customize a 5-flat trailer-side wishbone wiring kit (e.g., part # A25W5B) to wire up the taillights. I’d then use any 7-pole to 5-flat adapter to connect with my 7-pole vehicle outlet.

Main challenge: Most “wishbone” flat-wire trailer kits only send two wires in each “taillight bundle” [e.g., One tail light wire (brown) is bundled with left turn and brake wire (yellow), and one is bundled with right turn and brake wire (green)]. If I use this sort of 5-flat trailer wishbone kit:

1. Do I mate the appropriate functions from light to wishbone-bundle by splicing together, e.g. for the left light:
- Yellow (left turn/brake) from the wishbone bundle, spliced with …
- Yellow (indicator) and Red (Brake) from light pigtail?
What would be the best waterproof way to splice this? Can I connect all three wire ends in one spot?

2. Do I splice a second blue wire into the trailer side 5-flat connector, to create a blue wire “wishbone” (like the brown wire / taillight wishbone) to connect to the White (Reverse) wire on each taillight? (Why don’t any 5-flat trailer wiring kits make it easy to set up the blue-wishbone option for reverse lights?)

3. Would it be easier to just run a full 5-way flat wire out to each light, since the Light’s ground/negative wire also needs to go somewhere? Can I make the lights a little more “plug and play” with typical wishbone wiring by putting a connector of some kind on the 5-strand light pigtail?

4. Would it make more sense to install a 7-pole trailer-side wiring kit, in terms of fewer components/splicing/tweaks? Wouldn’t I have the same wish boning challenges?

5. Can I just crimp butt-end connectors and tape to splice, or should I solder these connections? This has to work for 2-3 weeks, but I could do a more permanent job later if they prove not waterproof enough.

Thanks for any tips!

Why not a pigtail like this https://www.etrailer.com/Wiring/Migh...d/A10-7W6.html connected straight to the pigtails on your lights, nothing in-between. Crimps are good ratchet or not ratcheted will hold fine but a crimp tool no pliers and be sure to get the entire striped wire all the way in before crimping and black tape, the 99 cent a roll stuff is good and can be stretched a bit to conform. And don't try to separate the brake/blinker function probably best to abandon the yellow lights. And I assume you'll grab the back up light circuit and wire to the aux pole of the 7 way or something like that maybe the brake pole.

[achop]

Originally Posted by MadScience

Looks like you edited, yeah ratcheting crimps are much more reliable. Normal ones work as well, particularly if you inspect the crimp carefully. However, it's not like ratcheting ones break the bank anymore.

Yep, you caught me ... I edited out my ignorant remark after answering my own question ;-)

I saw some ratcheting crimps, well reviewed, good price, but thick and heavy like a small pipe wrench. Maybe I can find some more "mobile" or travel size ones ;-)

[achop]

Originally Posted by FXRQ

Why not a pigtail like this https://www.etrailer.com/Wiring/Migh...d/A10-7W6.html connected straight to the pigtails on your lights, nothing in-between. Crimps are good ratchet or not ratcheted will hold fine but a crimp tool no pliers and be sure to get the entire striped wire all the way in before crimping and black tape, the 99 cent a roll stuff is good and can be stretched a bit to conform. And don't try to separate the brake/blinker function probably best to abandon the yellow lights. And I assume you'll grab the back up light circuit and wire to the aux pole of the 7 way or something like that maybe the brake pole.

So I finally read enough and diagrammed my project enough to understand what you and MadScience were trying to say: even the vehicle 7-pole port doesn't separate turn signals and brakes. (And even if turn and brake WERE separated at the 7-pole, the 5-way trailer connector wouldn't be enough to support 6 distinct functions: Left-Right-Brake-Reverse-Tail-Ground...doh!)

Both you and MadScience suggest abandoning the amber lights ... fine ... but why couldn't I just connect the Turn and Brake lamp wires (before feeding into the 5-way wishbone bundle) and get both amber AND red for my turns ... and... er... stops. Now googling to determine legality.

Also, re the 7-pole pigtail ... would be just fine and save a few steps, but I thought it might be handy to have a 2' extension/connector anyway (going 7 to 5) so I could:
- unplug the extension and stick in the van (not super critical - maybe dumb).
- splice a single "Tail/Running light" wire (for my license plate) into the extension. My license plate light wire would run into the top rear door from my license plate holder and out the bottom of the rear door OR sliced into a segment of the connector that I close *inside* the van. It's kind of messy tying i the license plate light, regardless of whether I include an adapter/extension segment. See license plate holder/light here:

[FXRQ]

You could grab a running light circuit from inside the van and run up to the lic light with it's own plug - disconnect. As for the amber/red config, sure you could do that but it might be a confusing signal for the folks behind you, don't wanna confuse the folks behind you.

[carringb]

I've seen commercial buses that run both pars of amber and red as combined brake/turn lights. I did it on my motorcycle rack too (side affect of having it show amber only when it's on the front). It's fine. And as far as I can tell, legal as long as you have the required red Brake/marker lights.

FWIW - eTrailer has a converter to split combined into separated circuits. It will flash red when using 4-way flashers, but otherwise works fine. I'll go this route when I add side turn signals to my big trailer.

[carringb]

PS - On my motorcycle rack I used the brake controller circuit for the red brake lights, so they don't flash with the ambers. Works fine since it's LED. Probably works fine too with incandescent if you turn the controller up all the way.