Does anything need to be changed software side to enable a DIY added OEM trailer wiring module for Model 3?

[rotarypower101]

Anyone possibly recognize this Brown plug type?
Believe it is the +12Vdc line passthrough on the Model S&X that can be used for trailer battery charging and for a brake controller where applicable.

If its available publicly, would like to pick up its Male counterpart.

 

[stopcrazypp]

Anyone possibly recognize this Brown plug type?
Believe it is the +12Vdc line passthrough on the Model S&X that can be used for trailer battery charging and for a brake controller where applicable.

If its available publicly, would like to pick up its Male counterpart.

View attachment 1059718
View attachment 1059719View attachment 1059720

Not sure if it will help, but from the thread about diy trailer harness, the connector for the taillights was made by TE Connectivity. Maybe you can find it in their catalog? Tesla also uses Delphi/Aptiv.

Build your own plug and play trailer harness!

Hey everyone, I just built my own plug and play 4-pin trailer harness for my 2018 Model 3. This is great because it is removable and requires no modification to the factory wiring harness. It can literally be installed in 5 minutes once the harness is complete. I cannot confirm this will work...

teslamotorsclub.com

Google lens found Porsche used a similar type of connector (although a bit different), for a cooling fan control unit:

Porsche 911 997.2 Turbo Boxster Cayman 987 Air Cooling Fan Control Unit '05-'13'

LA Dismantler Used Porsche Parts Salvage Junkyard Breaker Spares 911 Boxster Cayman Cayenne

ladismantler.com

The Porsche connector had some embossed text on the connector but not possible to read from pictures. Maybe check if yours also has it for clues of connector manufacturer or model?

 

[orangeCat]

Anyone possibly recognize this Brown plug type?
Believe it is the +12Vdc line passthrough on the Model S&X that can be used for trailer battery charging and for a brake controller where applicable.

If its available publicly, would like to pick up its Male counterpart.

from SOP15 Interactive on the Tesla service site's Model S 2021+ "circuit and connector reference" it's maybe an AMP something plug - see the popup for the connector model number. looks about right?

I also attached an image of what it plugs into. one of the wires is powered via a Brake Controller ECU under the control of Body Controller Left (and ultimately the brake pedal I guess), and the other wire is "Trailer_AUX" 12v direct from Body Controller Left.

 

[rotarypower101]

That looks like a strong lead, Thank You!

amp 1-1703543-0

And a number that seems to lead me to the Male counterpart
1J0973722

And a current option for a housing to create your own harnes.

 

[orangeCat]

That looks like a strong lead, Thank You!
amp 1-1703543-0

no worries!

so if that's the right part, then AMP 1-1355200-1 (from the lower popup) is most likely the "official" other side of your plug. but yup, there could easily be a bunch of equivalent and knock-off versions that'll work just as well...

FWIW Tesla has part numbers for the terminals (1-968857-1) and seals (828905-1) for that 1-1355200-1 connector too. they're here

X901F |

where "wire size" in the table is in mm^2.

if you're going to run a lot of power through it then using 2.5mm^2 (umm, 14 or 12 gauge?) wire and aiming for the correct large-ish terminals might not be a bad idea. I only mention this 'cos I noticed today that some of the cheaper connector sites assume we're going to use pretty thin wiring... :-/

 

[rotarypower101]

no worries!

so if that's the right part, then AMP 1-1355200-1 (from the lower popup) is most likely the "official" other side of your plug. but yup, there could easily be a bunch of equivalent and knock-off versions that'll work just as well...

FWIW Tesla has part numbers for the terminals (1-968857-1) and seals (828905-1) for that 1-1355200-1 connector too. they're here

X901F |

where "wire size" in the table is in mm^2.

if you're going to run a lot of power through it then using 2.5mm^2 (umm, 14 or 12 gauge?) wire and aiming for the correct large-ish terminals might not be a bad idea. I only mention this 'cos I noticed today that some of the cheaper connector sites assume we're going to use pretty thin wiring... :-/

Very helpful, thank you!

Targeting a Max of 6.4A@12Vdc.

If you have any background knowledge in connectors and terminals, might you have a recommendation for the specific terminal to select, and gauge of wire to select to pair with it?

A few online calculators say I should be able to get by with as low as 16Ga@~10' of length.
Was planning to match the Tesla harness (guessing ~10-12Ga), but don't have one in hand yet, as I am just speculating and planning for the future project ATM.