Does Your Car Have Soy Based Wiring? [UPDATED 2023] – How to Prevent Rats from Eating Your Car Wires (2024)

Starting in the early 2000’s, car manufacturers began using bioplastics* (e.g. soy based wiring) in cars. They state their reasoning was in an effort to reduce dependency on petroleum and to “go-green.” In reality, bioplastics are cheaper to produce.

*Note: For more information, see Bioplastics In Cars

At this point it is almost guaranteed that any car built in the last 10 years will have soy based wiring (more accurate list below). This has led to a surge of issues with wildlife, particularly rodents, being attracted to these wires for consumption. Now, not only are rodents attracted to the cars for shelter, but also for food.

In researching this back in 2017 (when I first launched this website), I was blown away by the number of complaints on websites, articles and forums of people reporting rodent damage on their newer cars.

To be honest, both of my cars that were attacked were newer at the time (2015 Honda, $2,400+ in damages, and 2012 Hyundai, $9,300+ in damages).

Soy Based Wiring Lawsuits

Multiple class action lawsuits were filed against Honda, Toyota, KIA, and Hyundai back in 2017.

Here is a list of each class action lawsuit (including some links to more information).

Albert Heber vs. Toyota Motor Sales, USA, Inc.
Janice Toler vs. Toyota Motor Corporation & Toyota Motor Sales, USA, Inc.
Daniel Dobbs et al. v. American Honda Motor Co. Inc.,
Tsvetelin Tsonev v. Kia Motors America Inc.
Darla Campbell, Tristin Hibler, and Michael Leppert, et. al., v. Kia Motors America, Inc.
Michelle Martinez v. Hyundai Motor America, Inc.

It should be noted that initially each of these cases was either dismissed or voluntarily dismissed back around 2018.

To be honest, I was not that surprised as rodents have been eating car wires for decades. And, from what I’ve read, the plaintiffs lacked sufficient evidence to prove that the soy based wiring was leading to an “increased” amount of rodent damage to cars.

Frankly, I’m not confident if we will ever have historical data to prove this aspect, especially, given all the other cases that aren’t even reported.

With that said, there is one lawsuit that still has a shred of life. Heber vs. Toyota was revived in 2020.

Which Cars Have Soy Based Wiring?

Is your car at risk? Here is a full list (Updated 2023) of all car makes and models that are known to have soy based wiring, starting with the first year:

Toyota

2012 to Present – ALL Toyota vehicles
2011 to Present – Toyota 4Runner
2009 to Present – Toyota Camry
2010 to Present – Toyota Prius
2011 to Present – Toyota Prius C
2008 to Present – Toyota RAV4
2009 to Present – Toyota Tundra
2009 to Present – Toyota Highlander
2010 to Present – Toyota Venza Ltd.

Honda

All 2012 to Present – ALL Honda vehicles

KIA

2012 to Present – Kia Soul
2012 to Present – Sorrento
2012 to Present – Sedona
2012 to Present – Sportage
2012 to Present – Forte
2012 to Present – Cadenza
2012 to Present – Optima
2012 to Present – Rio

Hyundai

2013 to Present – Veloster
2013 to Present – Accent
2013 to Present – Azera
2013 to Present – Elantra
2013 to Present – Equus
2013 to Present – Genesis Coupe
2013 to Present – Santa Fe
2013 to Present – Sonata
2013 to Present – Tuscon

I have also seen numerous complaints that reference earlier makes and models than what is referenced above.

Separately, I have seen reports of rodent damage due to soy based wiring on pretty much every large car manufacturer:

Audi
BMW
Dodge
Ford
Mazda
Nissan
Porsche
GMC
Chevrolet
TESLA!!
…and I’m sure there’s many more

To be frank, this is a HUGE ISSUE!!

So to answer the question, “are you at risk?”, if your car was made in the last 10 years, then YES! I think the evidence can’t be any more clear that if you own a newer car you need to take preventative action ASAP!

If you are reading this article, I could imagine either you are dealing with this issue or you have a friend that has rodent damage to their car. Here is an excerpt from the Home page (w/ edits for mice) that will tell you exactly what I have done to fix this problem:

“Before we get started I want to make it crystal clear that the instructions below explain the EXACT steps and products I used (and continue to use!) to successfully protect my car against rodents. This methodology factors in rodent behavior and psychology which makes for a very high probability of success.

Exactly How To Prevent Rats & Mice From Eating Your Car Wires

What you will need:

Tomcat Rat Snap Traps (6 traps per car) – For Rats
Tomcat Press ‘N Set Mouse Trap (6 traps per car) – For Mice
Grandpa Gus’s Double-Potent Rodent Repellent Spray(i.e. peppermint and cinnamon oil spray)
Bright Light (4 Flashlights or 1 Shop Light)
Optional: Galashield Owl Decoy with Rotating Head

Step 1:Leave Your Hood Up At Night

At the first sign of damage or rodent droppings in the engine compartment, it is essential to leave your hood up at night. You should do this for the first 1-2 weeks every night and then 2-3 times a week once you feel comfortable that there are no more rodents visiting your car. This essentially eliminates the engine compartment as a potential nesting grounds by taking away the warmth, allowing more moisture to enter, and exposing it to more light.

Step 2: Place Tomcat Rat Snap Traps (For Rats) or Tomcat Press ‘N Set Mouse Trap(For Mice) on the Tread of the Front 2 Tires

You will need 6 snap traps total and 3 will be placed at specific locations on the tread of the front 2 tires. Here is video to show exactly where to place the snap traps.

When rodents enter the car, they climb up the tread of the tires so this essentially will block off the entrance to the car. I use the Tomcat Rat Snap Trapsand the Tomcat Press ‘N Set Mouse Trapbecause they are super easy to set (i.e. I don’t feel like I am going to lose a finger when I set them), their design makes it almost impossible for a rodent to take the bait without setting off the trap, and they get the job done!

Step 3:Spray Grandpa Gus’s Double-Potent Rodent Repellent Spray into the Engine Compartment

In the first 1-2 weeks, spray the engine compartment 3-4 times a week and then reduce to 2-3 times week once you haven’t noticed any new signs of rodents. Grandpa Gus’s Double-Potent Rodent Repellent Spray is an all natural peppermint and cinnamon oil spray that was specifically created to deter rodents from chewing on wires. The purpose of the spray is to confuse the rodent on the safety of the engine compartment by making it more difficult to detect the scent of their urine. As mentioned in the enemy profile (on the Home page), rodents use urine as a way to mark paths, locations, food, etc., as safe.

Step 4: Shine Bright Lights on the Tread of the Front Two Tires

As mentioned in the enemy profile, rodents always prefer to stay concealed and hate being in the light. The goal of this solution is to deter the rodent from climbing up the tread of the tires by forcing it to walk through a spotlight to get into the car. It would be best if you laid out 4 flashlights on the ground level and shined them on the front and backs of the tread (i.e. essentially you would shine them on the snap traps that are at the bases of the tread). Alternatively, you could take a shop light and shine that under the car at night.

(Optional) Step 5:Place Galashield Owl Decoy with Rotating Headon the Ground Near the Car

This is more the cherry on top, but I have always used a Galashield Owl Decoy with Rotating Head in my lineup. You can just place it at ground level around the car and move to a different spot every few days. When a slight breeze picks up, it will also rotate the head which will in turn scare the rodents. To be honest, it’s effectiveness is unknown, but it makes me feel more comfortable.

I am certainly available if anyone has any questions or comments. Please drop a note below!

I hope that you have found this article to be helpful! Thank you!!

Rat King Dave

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Tags: Soy Based