Trailer reverse light wiring

Anyone know how the rare reverse lights mounted on the rear of some trailers (usually tankers & owner-op vans/reefers) are wired?

Is it possible to somehow use a standard 7 pin on an ABS equipped truck/trailer, or do you need to have an auxiliary cord?

Pics of a tanker & Bison transport trailer with reverse lights.

 

Those 2 pics are just stock Google pic footage to give examples so I cannot verify, but more than one Bison driver has confirmed they have reverse lights on newer trailers & the white LED lights appear to be either those or a white work light hanging below the outside brake lights.

As far as amber turn signals on the tanker, they are allowed; just for the fact that red is also allowed for some reason under the FMVS Standard 108.
Likely to simplify parts inventory & lower cost by minute amounts, we have just gotten used to red for turn signals & brake lights.

As long as you have the required minimum red brake/rear marker lights, you are allowed to have amber or red turn signals for that purpose, even when rear facing

Most of the rest of the world requires rear amber turn signals, & rightly so; the color is more eye catching & differentiated from the sea of red.
It also indicates a completely different action/intention.

Attached is a 2009 DOT study showing a small but measurable increased effectiveness of amber vs red turn signals in rear end collision incident prevention. (Study was for passenger vehicles but same results apply to trucks)

Also attached is some pics of Crete/Shaffer trailers with amber turn signals; guessing their flatbed division 'Hunt' (not JB) probably also has them.

 

What leads you to believe the amber is being used as a brake/tail light?

Table 1 towards the bottom of Standard 108 says a trailer only needs 2 red brake & 2 red tail (marker) lamps minimum.
Since you can combine the function of brake & tail into one unit, the tanker has the minimum required & chooses to use the allowable 2 minimum amber turn signals for that function.

https://www.gpo.gov/fdsys/pkg/CFR-2004-title49-vol5/xml/CFR-2004-title49-vol5-sec571-108.xml

Screenshot of table I am referring to.


Understand what you mean about the clear lights that light up red or amber, I guess as long as they are the color required when lit its ok?
Maybe hardliner DOT would snap them for it.

 

I confess to not understanding what he/you was/are talking about then.


Regardless, I think this tanker also serves to show the proper placement of turn signal vs stop/tail; evidentally the turn signals have a wider maximum allowable spacing (at 83in) then the tail lamps (at 72in)

Table II of Standard 108, proper light placement for vehicles/trailers over 80in wide.

https://www.gpo.gov/fdsys/pkg/CFR-2004-title49-vol5/xml/CFR-2004-title49-vol5-sec571-108.xml

Screenshot


So turn signals should legally & logically be at the furthest extremities of the trailer width (within the allowable specs) which I don't always see; the previous Crete/Schaffer pics included.

Fascinating stuff; now if only we could figure out if trailer reverse lights are wireable to a ABS trailer.

Our trailers have a constant on center pin for "more reliable ABS operation" but as I understand it, ABS can operate off the "stop lamp" circuit & the center pin can be an auxiliary.
This may just be our trailers or something Great Dane does.



The new ISO 12098 standard 15pin heavy duty trailer connection has a dedicated reverse light pin, among many other functions so maybe it will be a future requirement/more easily used option.

I definitely would like to have such lights when backing into enclosed docks & general tight & dark areas.
Make them LED flood lamps aimed about like fog lights are.
Can't believe its not standardized yet purely as a safety measure to let every one around & behind you know what is going on without/in addition to annoying beeper alarms.

No, flashers are not nearly as communicative of a reversing trailer, especially to non truck drivers.
They can indicate temporary parking, breakdown, slow travel in lane, emergency stop, & any number of other (insert here) informal meanings.