2025 OT+ AUX Switches wiring

[Lionxxx]

Did you buy the ebay listing above? Can you show pics of the connector end under the hood and the connector from the pigtail? Everything I have seen looks like the orientation is correct.

Yep, this cable I got from the link you posted. Here's a shot of Cable C — and the locking tab seems to face the opposite way from Cable B.

 

[jmercer46]

Thank you for confirming this. I will let the ebay seller know and see if he can build one with the locking tab oriented properly. I will also see if he can color code properly also. Thanks!

 

[Lionxxx]

Thank you for confirming this. I will let the ebay seller know and see if he can build one with the locking tab oriented properly. I will also see if he can color code properly also. Thanks!

I am thinking — would it be possible to remove the terminals from the eBay harness and insert them directly into the factory connector (Cable C) in the engine bay?

The idea is that since the eBay harness doesn’t physically fit Cable C due to the opposite locking tab, maybe I can just re-use the terminals by inserting them into the original factory connector, assuming the pin type and spacing match.

Here's a photo showing the connector mismatch — the tab orientation is reversed, but the pin structure looks pretty similar.

 

[jmercer46]

That is a good idea. I would say for sure that would work. But I am not sure how to remove them. I know they make the pin removal tool for a Deutsch connector, but no clue on these. The other thought would be to file down the locking tab on the ebay connector.

 

[jmercer46]

I sent message to the seller and will post what he says also.

 

[Garauld]

Based on my experience with these style connectors, you can unlock the pins and sockets by sticking a jewelers screwdriver into the circled holes shown in the attached image and push up a little while tugging on the wire. This should release the locking tab.

 

[Lionxxx]

I pulled out the wiring harnesses and reinserted them into the original vehicle's port.

 

[jmercer46]

Nice! Did the ends remove through the holes as stated by Garauld above? This looks like the best work around at this point in my opinion. Looks pretty slick too. Nicely done!

 

[Lionxxx]

Nice! Did the ends remove through the holes as stated by Garauld above? This looks like the best work around at this point in my opinion. Looks pretty slick too. Nicely done!

You need to pull out the white cover from the connector first, then use a pair of tweezers or another suitable tool to lift the locking tab while pulling the wire out at the same time.

I am just thinking right now about whether the wires with different colors correspond to the correct ports.

 

[jmercer46]

I labelled my wires to align with the Lexus GX550. these colors look right to me

 

[MandRautomotive]

Made a video of my project and how i did the AUX switches

 

[jmercer46]

Great instructions as always! The connector on the vehicle does show the black and white common ground wire that would pin in to the connector next to your aux 1 connection. Why did you choose to not use?

 

[MandRautomotive]

Decided it was easier to ground the lights on the chasis of the vehicle. That connector is a pain. Lexus could have done better

 

[TmoEng]

Decided it was easier to ground the lights on the chasis of the vehicle. That connector is a pain. Lexus could have done better

just got around to watching the step-by-steps on your YT channel. Thanks for making them, they are great

 

[MtnGX]

Don’t know but my light bar is hook up to aux 4 installed by dealer sorry not much only had a day

Do you know where the Aux 4 (D on diagram) connector is located? Under dash somewhere? So two connectors under dash?
I have a roof rack arriving shortly that needs a light bar. Also, did they run the wiring to the roof up the wide channel on the side of the windshield? Thanks

 

[jmercer46]

Aux 1 and Aux 2 on driver side front under hood. Aux 3 and Aux 4 on passenger side front under hood. Watch the above video and it will be extremely clear. Other connector under driver seat.

 

[jmercer46]

Color coding will be same on each connector based on the Lexus manual and will carry over to each connector.

 

[Finn GX]

It seems the 2025 4Runner Trailhunter and some PRO models also have a similar Aux setup as the 2025 OT, with the Aux 1 @40 A, Aux 2 @20 A, Aux 3 @15 A, Aux 4 @10 A. In reading some of the 4Runner G6 forums many, but not all, these models are coming with the pigtails in boxes, made in Mexico. I should have my 25 OT in about a month and will see if the Toyota pigtails work on the GX, if Lexus does not have them yet. The Toyota pigtails are different sizes for Aux 1 & 2 than 3 & 4 since they have more amps. The Toyota part numbers are:

PT974-89251
Hi AUX Wire Harness

PT974-89252
Low AUX Wire Harness

One is for Hi Aux 1-2, the other is Low Aux 3-4. Wonder when Lexus will have the pigtails ready, but just maybe the Toyota ones will work. The only downside would be that the wire colors are slightly different for the assigned Aux #'s.

 

[jmercer46]

It seems the 2025 4Runner Trailhunter and some PRO models also have a similar Aux setup as the 2025 OT, with the Aux 1 @40 A, Aux 2 @20 A, Aux 3 @15 A, Aux 4 @10 A. In reading some of the 4Runner G6 forums many, but not all, these models are coming with the pigtails in boxes, made in Mexico. I should have my 25 OT in about a month and will see if the Toyota pigtails work on the GX, if Lexus does not have them yet. The Toyota pigtails are different sizes for Aux 1 & 2 than 3 & 4 since they have more amps. The Toyota part numbers are:

PT974-89251
Hi AUX Wire Harness

PT974-89252
Low AUX Wire Harness

One is for Hi Aux 1-2, the other is Low Aux 3-4. Wonder when Lexus will have the pigtails ready, but just maybe the Toyota ones will work. The only downside would be that the wire colors are slightly different for the assigned Aux #'s.

Based on the wiring of the caps that MandR did, building our own pigtails has worked out perfectly. Watch the video if you can. The only difference that I did, was wire to the common ground in the pigtail rather than grounding on the chassis like mandr did.