Is 2003 Lexus GX470 Pre-Wired for Trailer Connector

Updated 06/12/2021 | Published 06/11/2021

Products Featured in This Question

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

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Tekonsha Plug-In Wiring Adapter for Electric Brake Controllers - Toyota and Lexus

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Hopkins Plug-In Simple Vehicle Wiring Harness for Factory Tow Package - 7-Way and 4-Flat Connectors

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Hook Probe Circuit Tester

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Tekonsha Primus IQ Trailer Brake Controller - Up to 3 Axles - Proportional

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Question:

Hi! How can I find out if I have a 4 way or 7 way connector for my GX470 2003. I just bought the Drawtite hitch from you. Please take a look at my photo of the existing connectors. Thanks

asked by: Thomas W

Expert Reply:

Given the connectors shown in the photo, although your 2003 Lexus GX470 wasn't equipped with the factory 7-way trailer connector, it looks like it's pre-wired for one. The connectors shown match up perfectly with the # HM43374 7-way trailer connector for the 2003 Lexus GX470.

You'll want to use a circuit tester like # PTW2993 on the pins of the 2 connectors you found to see if they're active. I've provided a photo showing how they're pinned out; your connectors will be a mirror image of the provided pinout photo. With the ignition on, you should see power on the 12-v pin, and power on the taillight/turn signal/brake lamp pins as each function is activated. If not, you'll need to check the fuse box to ensure the fuses for those functions are installed. If they aren't, you'll need to install them to activate them.

Luckily enough, I was able to find a .pdf copy of the owner's manual online, which isn't typical of older vehicles and was able to find the location and rating of the tow package fuses:

• Location 7, 30A Fuse- Power to Brake Controller
• Location 9, 30A Fuse- 12-V Feed to Trailer
• Location 10, 40A Fuse-Trailer Lamps
• Location 42, 30A Fuse-Trailer Taillight Converter

Once the fuses are in place and the # HM43374 is installed, you should be good to go. If the trailer you'll tow has brakes, you'll need to install a brake controller. I'd recommend a proportional controller like the Tekonsha Primus, part # TK90160. You'll also need the brake controller harness, part # 3040-P. The connector under the dash that the # 3040-P plugs into should be located above the e-brake pedal, just above the kick panel.