no trailer lights. real time help.

[Prophecy]

So I ordered the hidden hitch from e-trailer last week had a few issues, but that's another story for another time.

My major problem is that my gx did NOT come with a factory hitch but had the factory harness on the drivers side of the vehicle next to the spare tire. Hooked everything up and I have no trailer lights. BTW I am a licensed electrician and a mecp first class installer and know very well how to use a meter.

There is no power coming out of the factory harnesses at all. On my LX450 there was a small trailer pack on the inner passenger side panel in the rear that went bad and didn't allow any lights until I replaced it. Is there a hidden pack on the gx preventing this or am I looking for something else.

All fuses have been checked 3 under hood 1 in drivers side panel all have voltage, and have continuity through them telling me they are fine.

Jeremy
316-990-2371 if ya can help via phone vs here, but either will work. Thanks in advance for your time.

 

[wingysataday]

On our mini van I had to physically ground the white wire to the body. Nothing will work if this is not done.

 

[Prophecy]

Appreciate the idea, I checked continuity between the ground plug and the trailer, along with the ground plug and the vehicle, on both I got a complete circuit.

Appreciate the thought though I have had that issue before on our bumper pull camper and our f250. Was able to put a small piece of steel wool in the ball to create a good circuit until I got it home then attached a ground for a more permanent connection.

Jeremy

 

[NMBruce]

First, are you staying 7 pin to 7 pin or dropping down to 4 pin?

Also this might help you step back and look at it again
Trailer Wiring Diagrams | etrailer.com

 

[Prophecy]

Its a plug and play harness that has a 7 pin AND the 4 plug on it from trailer. That is not where the problem is, it is at the two plugs it goes to under the back of the vehicle on the drivers side. Same wires that plug into the factory harness just to the left of the spare tire.

I have no power at those plugs. Going from ground to any of the connections I have nothing while lights are on, running lights on, blinkers, hazards, etc. There has got to be something with the vehicle itself.

I have had several calls into my local Lexus dealership with no responses. There has to be a relay, box, or light booster located somewhere. I'm just trying to avoid tearing apart the entire interior to find it.

Thank you though,
Jeremy

 

[Prophecy]

OK so I finally found this information that seems to be ONLY with the 03 GX470s. I will call around and try to get it taken care of tomorrow. Will fill you in on the results.

Answer #1

Next, you will need these two relays 90987-02025 and 81985-60021 for the laight to work. The first one you can buy from Denso product part number DEN567-0003, the other one you will need to buy from lexus. the first one is installed in thr front fuse box, the second one install in the back next to the back light on the driver side.

Answer #2

To make it work, you'll need a relay for the front and a big green relay installed in the back, under the trim panel, by the drivers side brake light. you can get the front relay at a Toyota dealer for a reasonable price, but I got my rear relay from Sewell. Doing the electrical this way will my your GX trailer wiring pretty much the way it would have come from the factory. I don't know what the part numbers are, but Sewell faxed me a diagram that had all of the part numbers that I needed, along with their installation locations.

Guess we will see tomorrow,
Jeremy

 

[GXO]

Left rear quarter. Good luck! hope this helps

 

[Prophecy]

Thanks Dan. Will try locating the parts tomorrow if I get it all up and running I will make sure to take good pics of the install parts, model #s, to assist future peoples with this headache.

Jeremy

 

[moab cj5]

I have the same problem, but can't locate the green relay. It is discontinued and very hard to find in a junk yard. I have tried ordering online twice with my orders being canceled both times. If anyone knows where to get the green relay for the rear drivers side harness, please post up!

 

[moab cj5]

My dad built a relay for me to replace the one you can't buy. I now have trailer lights. it's probably easier to just ignore the factory harness and wire into the the existing lights.
Good luck!