Troubleshooting 4-Way Vehicle Wiring Harness Not Allowing Brake Lights to Work on 2003 Toyota Tacoma

Question

Question:

Hello Etrailer team, I have used your wiring harness installation kit from Curt for my 2003 tacoma double cab. I am at the final stage of connecting the harness and grounding it. Everything is working properly, but my brake lights. It appears that they are now always on, or maybe they are just at tail light brightness. Either way pressing and depressing the pedal makes no difference in the brightness of the taillights. The tail lights are aftermarket LED. Could this be having an impact on the harness or is this likely being caused by something else?

asked by: Chris B

0

Expert Reply:

The 4-Way Harness # C55379 for your 2003 Toyota Tacoma is going to use the factory wiring to identify when a function is activated and power the trailer connector. Since you mentioned your truck was converted to LED lights if you factory lighting has a resistor installed going to the brake lights this may prevent enough power from getting to the tail lights. You may have to either move the resistor or go with a powered module like the # C59236. This has a separate power wire which runs to the battery so that all the power sent through the converter is coming from the battery rather than the factory wiring.

I would start by testing the input wire going into the converter you just installed to verify you are getting power from the brake switch. I have also seen the fuse for the brake lights go out because the battery wasn't disconnected and there was a power short during installation. Since both the brake lights aren't working I feel like this is the most probable issue. Please let me know what you find or other tests you may have done so I know where to go further to help you determine it the converter was bad from the factory.

expert reply by: Bud M

0

Answer 1

Although we do not carry the Curt 59146 I can tell you that the red wire connects to the brake light wire on your 2014 Volkswagen Jetta. This is a 3 to 2 wire converter so it will combine the brake and turn signals to be compatible with the trailer…

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Answer 2

It's possible that you are drawing too much amperage on the running light circuit of the part #118562 that you installed. The running light circuit can only draw up to 7.5 amps so if you have a lot of running lights/clearance lights on your…

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Answer 3

It sounds like you have one of two things going wrong on your trailer wiring setup. Either you aren't using the correct circuits when you wired up the Curt Harness part #C59236, or the trailer you are towing has weak grounds and can't handle…

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Answer 4

I spoke with my contact at Curt, manufacturer of the #C59236 wiring harness for the 2011 Kia Sorento. He stated that he has not heard of this problem, but there is a test you can perform to help narrow down the problem. You will need a circuit…

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Answer 5

You can expect the installation of the #C59236 in the 2023 Palisade video to be almost identical to your 2022 Hyundai Tucson. I'm not sure if the tail light style varies so removal may be a little different but the rest will be the same.

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Answer 6

When installing the #C59236 there is a wire that runs to the vehicle's positive post and there is a wire that needs to be grounded. Failure to do both will result in the harness not working properly. Make sure you have the white wire grounded and…

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Answer 7

Yeah, it is definitely a bit to sort through, so I think we can help you out with the right 4-way wiring harness for your 2024 Kia Telluride. We'll start with the easy one, which is if you want to hardwire a 4-way, the model of your Telluride…

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Answer 8

Since you have some working functions, but not all, there is usually a problem with the connections themselves or the wires. I recommend checking the trailer wiring for corrosion within the connection made with your new harness. If there is not…

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Answer 9

Where did you find an install video for the C59236 on a 2010 Volkswagen Tiguan? It's not on our site anywhere, but to answer your question the brown wire is the running light circuit like you mentioned.

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Answer 10

The difference between the Class II and Class III hitches has to do with their Gross Trailer Weight (GTW), their Tongue Weight (TW), and their Hitch Receiver Size. Class II trailer hitch receivers have a 1-1/4 inch receiver and can be rated up to…

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Answer 11

A 4-Way trailer connector has the basic lighting functions only; running lights, left turn signal and brake lights, right turn signal and brake lights, and ground. A 7-Way has these functions and a 12 volt circuit, a circuit for electric trailer…

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Answer 12

The OEM prep package consists of 4 "pucks" in the bed of the truck that will allow you to drop in puck style hitches for easy installation and removal, that gives you a completely clear bed when not in use. The B&W Companion OEM 5th…

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Troubleshooting 4-Way Vehicle Wiring Harness Not Allowing Brake Lights to Work on 2003 Toyota Tacoma

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