Who Pays When a Rat Eats the Wiring: The Soy Insulation Lawsuits and a Question Nobody Tested

1. Introduction: a hypothesis we left open

Our article Twenty-Five Per Cent of Unknown traced a fire statistic this trade repeats, and along the way found a more interesting claim buried in a patent. We reported it, called it testable, and moved on. This article goes back for it.

1.0b And it was written without deciding whether it was true

An appeals court reviewing a dismissal asks whether the allegation is plausible, so the sentence describes what the owners claimed rather than what the court found.¹

1.1 Which is a sentence about who pays

Dressed as a sentence about what went wrong.¹

1.2 What this article argues

That the litigation turned on whether the animal or the attractant is the cause, that this is the same question insurance exclusions and rental disputes turn on, and that a decade of cases allocated the cost without anybody establishing the fact underneath. Sections 14, 15 and 22 are the case.

2. What the earlier article found

In a patent's background section.

The patent stated that it had been postulated that a transition from petroleum-based cable components to more plant-based biodegradable materials had increased rodent wire damage, because rodents were supplementing their diets with the plant-based components. Our earlier article noted that by whom was not stated, and that the claim was specific and testable where the fire statistic was not.

2.0a We called it the better kind of claim

Because it named a mechanism, predicted something observable and could be checked, which is what the fire statistic in that article could not do.

2.0b And the same document proposed a second mechanism

That rodents are drawn to energised wiring for warmth, which would operate whatever the insulation is made of. §28 returns to it.

2.1 We did not pursue it

Which is the gap this article fills, and we say so at the outset because the previous article is the reason this one exists.

3. What happened to it instead

The hypothesis did not go to a laboratory. It went to court, in suits against several manufacturers, from at least 2016.⁷⁶

3.1 Which is a common fate for a pest claim

A hypothesis about animal behaviour becomes a dispute about money before anybody observes the behaviour, and the dispute is then settled on rules that do not require observation.

3.2 And it spread across manufacturers

Toyota, Honda, Kia and Hyundai are all named in reporting on these suits, which makes it an industry question rather than a single company's design.⁶¹⁰

4. The claim as pleaded

In one owner's complaint.

The inclusion of soy-based materials in class vehicle electrical wiring and wiring components attracts rodents and other animals that nest under the hoods of class vehicles and feast on the soy insulation and electrical wires.⁶

4.0b And the animals named are not only rats

Rodents and other animals in one complaint; mice, rabbits and squirrels in another, which widens the claim from one species' diet to a general attraction.⁶⁷

4.1 Feast is the pleading's word

Which asserts the dietary version of the hypothesis, the one the patent described as postulated, as a fact.⁶

5. Cheaper as well as greener

The motive the complaints allege.

One complaint describes the coating as environmentally friendly and less expensive,⁶ and reporting on another suit says the coating costs less than plastic.⁷

5.0b Two motives that point the same way

A material that is both greener and cheaper has no internal cost pressure against adoption, which makes a hidden external cost exactly the kind nobody inside the decision would price.

5.1 Which is where the economics begins

If the substitution saved the manufacturer money and increased damage borne by owners, it moved a cost from one party to another. Both halves of that sentence are allegations, and the second is the one nobody tested.

6. The comparison nobody measured

Stated in a complaint.

While class vehicles are essentially being attacked by rodents and other animals, older vehicles with non-soy-based insulated wires that are exposed to similar conditions do not experience rodent-caused damage.⁶

6.0b Similar conditions is doing the work

Older vehicles are driven less, parked differently and owned by different people, so a fair comparison would have to hold those things constant, which an owner's observation cannot.

6.0c And the reporting cites consumer complaints instead

Complaints lodged with a federal safety agency describing rodent wire damage, which show that owners experienced damage but not that the material caused it.⁶

6.1 This is the claim that would settle everything

A comparison of damage rates between insulation types under similar exposure is exactly the test our earlier article called for.

6.2 And it is asserted, not reported

No study is cited for it in the reporting we read, and the categorical form, do not experience, is not how a measured difference would be described.⁶

Sections 6.1 and 6.2 are ours.

7. The defence

Which rests on history.

Toyota's position is summarised as arguing that rats and other creatures have chewed on things throughout history and vehicles from other automakers suffer the same fate.⁵

7.0b And it is true as far as it goes

Rodents have chewed wiring for as long as there has been wiring, which our damage statistics article accepted without needing a number. The question is whether the rate changed.

7.1 Which is also an untested comparison

Other manufacturers' vehicles suffering the same fate is the mirror image of §6, asserted with the same absence of data.

8. No evidence they like the taste

The sharpest defence argument.

Kia urged a federal judge to dismiss a similar suit because no expert evidence showed rats and other critters even like the taste of the material.⁶

8.0b Taste is the right question for the dietary version

If rodents eat the insulation because it is food, they must find it palatable, and palatability is exactly what a choice test measures.

8.1 Which is correct as far as we can tell

We found no such evidence either, which §25 describes and §29 records.

8.1b And the argument was made in 2017

Nine years before this article, which is ample time for somebody to have run the test the argument said was missing.⁶

8.2 And it is not the same as evidence that they do not

The argument succeeds by pointing at an absence, which is a statement about what has been studied rather than about rodents.

9. The Toyota case

The owners alleged that because Toyota switched its wiring harness from vinyl chloride to a soy-based material, rodents were more attracted to their vehicles and caused damages.¹

9.1 Vinyl chloride to soy

The alleged change is from a conventional plastic insulation to a plant-based one, which is the petroleum to plant transition the patent described.¹

9.2 And the case ran for years

Filed in 2016 and still active after the 2021 ruling, which is the most sustained attempt we found to put the hypothesis to any test at all.⁴

10. Dismissed, and why

After four attempts.

The district court dismissed the fourth amended complaint for failure to plead with particularity under the federal rules, and found that the soy-based wiring did not constitute a latent defect.¹

10.0b Four chances to plead it better

The owners had four opportunities to refile before the dismissal, which suggests the difficulty lay in stating the facts with the required specificity rather than in any single drafting error.⁵

10.1 On pleading, not on evidence

A motion to dismiss asks whether the complaint states a claim, not whether the facts in it are true, so no court at this stage heard evidence about rodents or insulation.

10.1b Latent defect was the other ground

A defect hidden at purchase that later causes failure. The district court held that the wiring was not one, and the appeals court disagreed about when the defect existed.¹

10.2 And one ruling went further

Observing that only after the rats do their work does the vehicle become inoperable (if at all).³

11. The external actor

The district court's framing.

Plaintiffs are, in effect, asking the court to stretch the implied warranty of merchantability to include some promise that no external actor will later harm plaintiffs' vehicles. The court declines to extend the doctrine so far.³

11.0b Which is a coherent reading of a warranty

A seller warrants the product, not the world it is used in, and a court is entitled to decline to treat a rodent as part of the product.

11.1 Reported elsewhere with a phrase

The judge was reported as holding that the implied warranty could not be made to cover damage caused by those pesky rats.⁴

12. The appeal

Partly successful.

The appeals court affirmed the dismissal of claims under thirteen states' consumer protection statutes and reversed the district court's dismissal of Appellants' implied warranty of merchantability claims and federal warranty act claims, with the exception of abandoned claims under three states' law.¹

12.0a The appeal did not reach the evidence either

Like the district court, the appeals court was deciding whether the claims had been adequately alleged, not whether rodents prefer the material.¹

12.0b So the fraud theory failed and the warranty theory survived

Claims that the manufacturer concealed something were finished. Claims that the product was not fit for ordinary use were not.¹

12.1 In an unpublished disposition

Described as not appropriate for publication and not precedent except under the circuit's own rule, which limits its reach beyond this case.²

13. The defect is the attractant

The appeals court's reasoning.

The alleged defect was the wiring that attracted the rodents, and this defect existed at the time of sale even if the damage only occurred later. To hold otherwise would require that the damage, not just the defect, exist at the time of sale.¹

13.0a Which moves the question from the animal to the design

Once the wiring is the alleged defect, the rodent becomes the means by which the defect shows itself, in the way a crack shows a weakness in a beam.

13.0b And the reasoning is about ordinary use

The implied warranty protects ordinary use, and ordinary use of a vehicle includes parking it where rodents live, which is everywhere.¹

13.0c That extension of the reasoning is ours

The court held only that the alleged defect existed at sale, not that rodent exposure is ordinary use.

13.1 Which the lower court then applied

In 2021 the district court held itself bound, saying that to dismiss the implied warranty claims now would contravene the circuit's clear mandate and relitigate issues it had decided.⁴⁵

14. Two framings of one fact

Nothing about the rodents, the wires or the damage differed between the two rulings. What differed was whether the animal or the thing that drew it was treated as the cause.

14.0a And a third court could go either way

Because the choice between the framings is a legal judgement rather than an empirical one, nothing in the evidence forces it.

14.0b Which is not a disagreement about facts

Both courts took the allegations as given. The disagreement was about which link in the causal chain the law should attach responsibility to.

14.1 And each framing allocates the cost

An external actor is nobody's warranty. An attractive defect is the seller's.

Sections 14 and 14.1 are ours.

15. Which is the question this journal keeps meeting

In other dress.

Integrated pest management teaches that the conditions attracting a pest are the problem and the pest is the symptom. The appeals court reasoned the same way about wiring. The district court reasoned the way a householder does: the rat did it.

15.0b Neither court was reasoning about pests

Both were reasoning about warranties, and arrived at the two positions pest management has argued over for decades without either one citing it.

15.1 And the law has no settled view

Two courts in one case took opposite positions, which is some measure of how open the question is.¹³

16. The insurance version

From our uninsurable damage article.

That article found vermin damage excluded from property policies on grounds of gradualness and preventability. The district court's external actor reasoning sits comfortably beside it: damage by an animal is nobody's covered risk.

16.0b Gradualness and preventability both apply

Rodent wire damage accumulates over nights and can be deterred, which are the two grounds our insurance article found underlying the vermin exclusion.

16.0c And a warranty and a policy answer the same question

Both decide in advance who bears a loss nobody wanted, and both have reached for the external actor reasoning when the loss involves an animal.

16.1 The appeals framing would sit less comfortably

If an attractant is a defect, then a building condition that draws rodents might be treated the same way, which no policy we examined contemplates.

17. The rental version

From our Manitoba tenancy article.

Disputes over who pays for pest control in rented homes turn on whether the pest arrived from the tenant's conduct or the building's condition, which is the same choice between actor and attractant.

17.1 With the same stakes

Whoever is found to have created the attractant pays for the result, and whoever is found merely to have suffered the visit does not.

17.2 And the same evidential gap

Our tenancy article found the origin of an infestation rarely established by anything better than the parties' competing accounts.

18. The Honda cases

Several of them.

In 2016 an owner of a 2012 Accord that needed repairs twice filed a breach of warranty suit, and in 2018 an owner of a 2015 Accord filed another; both were dismissed shortly afterward.⁸ A later suit in Illinois was dismissed by a federal judge whose opinion referred to the city's rodent problem.⁹

18.0b And the context cuts against the owners

A city with many rodents is one where any wiring would be attacked often, so if the opinion relied on that context it points toward the rodents rather than the insulation as the cause.⁹

18.1 Chicago as context

Reporting on that dismissal notes a pest control company's survey ranking Chicago the most rodent-infested city, and describes the judicial opinion as mentioning the context of the city's rodent problem.⁹

18.2 We did not read the opinion

So we cannot say whether the judge cited the survey or the reporter added it.

19. The deterrent tape

The detail every account repeats.

One owner argued Honda knew of the problem, as evidenced by its sale of a specialized Rodent Deterrent Tape,¹¹ and another cited mechanics repairing his wiring with that tape as proof the company was aware.⁸

19.1 Sold by the manufacturer itself

Which is what makes it rhetorically powerful: a company marketing protection for its own component against the very animals the complaint names.⁶

20. Which reads two ways

Our reading.

A manufacturer selling a product to protect its own wiring from rodents may know the wiring attracts them. It may equally know that rodents damage all wiring and be selling a remedy for a general problem. The tape is consistent with both.

20.0b And the tape was used in repairs

Which is what one owner relied on, reasoning that a repair method treating the wiring as a target concedes that it is.⁸

20.0c And a manufacturer has reasons to sell it either way

Owners with chewed wiring want a remedy, and a dealer able to sell one gains whether or not the material contributed.

20.1 And it proves demand rather than cause

That owners wanted protection is established. Why their wiring needed it is not.

21. Every case dismissed, except the one that was not

A claim repeated in reporting.

A broadcaster reported that every case was dismissed, with the companies asserting they were not responsible for the rodents,¹⁰ and a motoring site that Toyota had been sued multiple times without any attempt resulting in compensation or a recall.⁸

21.0b And repeated with confidence

A broadcaster, a motoring site and a retailer each state it, which is the pattern our citation trail article described: a claim becoming more certain as it travels.¹⁰⁸¹¹

21.1 Which is at least incomplete

The Toyota case was revived on appeal in 2020 and allowed to proceed in 2021, so not every case ended in dismissal.¹⁴

21.1b The error has a direction

Rounding a partial revival down to dismissal makes the litigation look more settled against owners than the record shows, which is the version a manufacturer would prefer.

21.2 And we do not know how that case ended

Whether it settled, went to judgment or was later dismissed is not in any source we found, which §29 records as the article's central factual gap.

22. Burden of proof as a cost allocation

Our argument.

A plaintiff must plead and eventually prove that the wiring attracted rodents. Without that proof the claim fails and the owner pays. The empirical question does not need to be answered for the cost to be allocated; the burden answers it by default.

22.0a And the owner cannot run the test

A feeding trial or a fleet-wide damage comparison is beyond any individual plaintiff, so the burden sits with the one party structurally unable to discharge it.

22.0b And the burden is unavoidable

Somebody has to bear it, and placing it on the party making the claim is the ordinary rule for good reasons. The difficulty is that here nobody holding the evidence had any reason to produce it.

22.1 So absence of evidence decided the outcome

Not evidence of absence, which nobody produced either.

23. Who could have answered it

Our reasoning.

A manufacturer has test facilities, material samples, warranty claim records by model and year, and the resources to run a feeding trial. An owner has a chewed harness and a repair bill.

23.0b Insurers hold records too

Comprehensive claims for animal damage by vehicle model and year would show whether rates changed with the material, and an insurer has some interest in knowing.

That is our speculation and we found no insurer analysis.

23.1 And the party able to test has no reason to

Since the burden sits with the owner, not knowing costs the manufacturer nothing, and knowing might cost it a great deal.

23.2 Which is the efficacy data problem again

Our articles on registration found evidence held by the party it favours and unread by anybody else. Here the evidence may not exist at all, for the same structural reason.

24. The commercial sources on both sides

Asserting opposite things with equal confidence.

An entomologist at a pest control company told a broadcaster that when you use a soy-based oil, now all these wires smell like food.¹⁰ A retailer selling rodent deterrent products states that there is no definitive scientific evidence that soy-based insulation attracts rodents more than other wire coatings.¹¹

24.0b And the pest company claim is more specific than it sounds

Smelling like food is a claim about attraction at a distance, which is testable separately from whether rodents actually eat the material once they arrive.

24.0c And the retailer's position is the more cautious one

Which is unexpected, since a seller of deterrents might be expected to prefer the more alarming account.¹¹

24.1 Neither cites a study

And each position suits a commercial interest, one selling treatment for an attractant problem and the other selling protection for any wiring.

25. What the test would look like

Our proposal.

Offer caged rodents equal access to conventional and plant-based insulated wire and measure material removed. Then compare warranty or insurance damage rates between comparable vehicles before and after the material change, controlling for parking environment and region.

25.0b And each answers a different version of the claim

The feeding trial tests palatability; the records comparison tests whether damage actually rose. A material could fail the first and still show the second through some other route.

25.1 Neither is difficult

The first is a standard choice feeding trial of the kind our house fly article described, and the second uses records manufacturers and insurers already hold.

25.1b And the second may have a natural experiment built in

If the material change can be dated to particular model years, which our sources do not do, it would give a before and after on otherwise similar vehicles, as close to a controlled comparison as field data gets.

25.2 We found neither done

In the published or reported material available to us.

26. What we take from it

Three things.

Who pays for pest damage depends on whether the animal or the attractant is the cause. Section 14.¹

Burden of proof can allocate a cost without the underlying fact ever being established. Section 22, which is our argument.

And the hypothesis our earlier article found remains exactly as untested as it was. Section 25.⁶

26.1 And one thing we cannot take from it

Whether the owners were right, which is the only question that a decade of litigation and our own two articles have left entirely open.

27. Our own position

The disclosure.

The soy explanation circulates in this trade as settled, and a pest control company answering a question about rodents in a vehicle is likely to repeat it. This article says it is not settled, and that the confident version comes from the same kind of commercial source as §24.

27.0b And what a company should say instead is short

That rodents chew wiring is certain; that some materials attract them more is unproven; and that a warm engine bay in winter is a refuge is plausible and also unproven.

27.1 And the attractant framing flatters our trade

An industry that sells the removal of conducive conditions benefits from a legal theory that conditions are the defect, which is a reason to hold that theory to a higher standard rather than a lower one.

28. The Manitoba position

28.0b Which makes the question practical here

Vehicles parked outdoors through a long winter are an obvious refuge, so what a pest control company tells an owner about the cause is a question with local consequences.

28.1 Vehicles here sit outdoors in deep cold

Which makes an engine compartment after a drive one of the warmest refuges a rodent can reach in winter, whatever its wiring is made of.

28.2 Which connects to the warmth mechanism

The same patent our earlier article quoted proposed that rodents are drawn to energised wiring for heat, a mechanism that would operate regardless of insulation chemistry and would be strongest in a cold climate.

28.2b And the two mechanisms predict different things

A dietary attraction to plant-based insulation should show up in any season. A thermal attraction should concentrate in cold weather on recently driven vehicles. Local repair records by month could tell them apart.

28.3 What we could not find

Whether the provincial public auto insurer covers rodent damage, any Canadian litigation on insulation, and any local data on rodent vehicle damage by season.

29. Limitations and open questions

We do not know how the Toyota case ended. It was revived in 2020 and allowed to proceed in 2021, and nothing we found reports what happened next, so §21 corrects a widely repeated claim without being able to supply the true ending.⁴

That is the most important limitation because a settlement, a judgment or a later dismissal would each change how the article's account of cost allocation should be read.

We did not establish what the insulation is. Soy-based is the term used in the complaints and the courts' summaries of them, and we did not verify the actual composition of any manufacturer's wiring.¹

The plaintiff counts disagree. One report describes 21 people in the Toyota case and another eight customers filing a consolidated complaint, which may reflect different stages of the litigation.⁴⁵

Most sources are news and commercial. Only the appeals court disposition is a primary legal text we read directly, and the district court's language reaches us through class action reporting sites.¹³

The repair figures in §5's chart are individual claims. They describe two owners' losses and say nothing about typical costs.⁶¹²

We make no claim about our own customer conversations. Section 27 describes what the trade commonly says, not a record of what this company has said, which we have not audited.

Sections 5.1, 6.1, 6.2, 14, 15, 20, 22, 23, 25 and 27 are our reasoning. The reading of the two judicial framings as a cost allocation, the argument about burden of proof, the account of who could have tested the claim and the proposed test are ours rather than sourced positions.

30. Conclusion

Our earlier article found, in a patent's background section, the unattributed claim that a shift from petroleum-based to plant-based wire insulation had increased rodent damage because rodents eat the new material, and called it testable. It was never tested. It was litigated instead. From at least 2016, vehicle owners sued several manufacturers alleging that soy-based insulation, adopted because it was environmentally friendly and less expensive, attracted rodents that feasted on it.⁶⁷ One complaint asserted that older vehicles with conventional insulation under similar conditions do not experience such damage, which is exactly the comparison that would settle the question, stated without data.⁶ The defence answered with an absence: one manufacturer argued there was no expert evidence that rats even like the taste of the material, another that rodents have always chewed things and every make suffers the same.⁶⁵

In the most developed case, a district court dismissed four amended complaints for failure to plead with particularity and held that owners were asking a warranty to promise that no external actor would later harm their vehicles.¹³ In 2020 an appeals court partly reversed, holding that the lower court had incorrectly identified the rodents as the defect, when the alleged defect was the wiring that attracted them, which existed at the time of sale; in 2021 the case was allowed to proceed.¹⁴ Nothing about the animals, the wires or the damage differed between those rulings. What differed was whether the animal or the attractant was treated as the cause, and that choice decides who pays. It is the same choice insurance exclusions make about vermin and tenancy disputes make about infestations, and integrated pest management makes about conducive conditions.

Other suits were dismissed, and reporting now says that every case was, which the Toyota appeal shows is at least incomplete; we could not find how that case ended. What is clear is that a decade of litigation allocated the cost of rodent wire damage to owners without anybody establishing whether the insulation attracts rodents at all. Burden of proof did the work: the owner must show the wiring is to blame, and the party with the test facilities, the material samples and the warranty records has no reason to find out. A pest control company's entomologist says the wires smell like food; a retailer of deterrents says there is no definitive evidence. Neither cites a study. A choice feeding trial and a before-and-after comparison of damage records would answer it, and we found neither. This trade repeats the soy explanation as though it were settled. It is not.

References

1. Memorandum disposition of a federal court of appeals in an appeal by vehicle owners against Toyota concerning soy-based wiring, 2020, reproduced on a legal information site. Primary legal text and the strongest source in this article. Source for the summary of the owners' allegation that because Toyota switched its wiring harness from vinyl chloride to a soy-based material, rodents were more attracted to their vehicles and caused damage; for the account that the district court dismissed the fourth amended complaint for failure to plead with particularity and found that the wiring did not constitute a latent defect; for the court's affirmance of dismissal of claims under thirteen states' consumer protection statutes; for its holding that the district court incorrectly identified the rodents as the alleged defect when the alleged defect was the soy-based wiring harness that attracted the rodents in the first place, a defect existing at the time of sale even if damage occurred later, since holding otherwise would require that the damage and not just the defect exist at sale; and for its reversal of dismissal of implied warranty of merchantability and federal warranty act claims, except abandoned claims under three states' law. https://caselaw.findlaw.com/court/us-9th-circuit/2081897.html
2. The same appellate disposition as reproduced on a public court records site. Primary legal text. Source for the notation that the disposition is not appropriate for publication and is not precedent except as provided by the circuit's own rule, and that a district judge from another circuit sat on the panel by designation. https://www.courtlistener.com/opinion/4776703/albert-heber-v-toyota-motor-corp/
3. Report on the dismissal of the Toyota soy wiring class action, published by a class action news site in June 2018. Legal news material reproducing passages of the district court order, which we did not read directly. Source for the quoted observation that only after the rats do their work does the vehicle become inoperable, if at all; for the quoted holding that the plaintiffs were in effect asking the court to stretch the implied warranty of merchantability to include a promise that no external actor would later harm their vehicles and that the court declined to extend the doctrine so far; and for the dismissal of state consumer protection claims because the plaintiffs had not established what, if anything, the manufacturer should have disclosed. https://topclassactions.com/lawsuit-settlements/lawsuit-news/toyota-soy-coated-car-wires-class-action-lawsuit-gets-dismissed/
4. Report that the Toyota soy wiring class action could proceed, published by the same class action news site in May 2021 and drawing on legal trade reporting. Legal news material. Source for the district judge's 2021 statement that the court was bound by the appeals court's findings and that dismissing the implied warranty claims would contravene the circuit's clear mandate and relitigate issues it had decided; for the description of the class as 21 people whose vehicles were damaged; for the report that in 2018 the earlier district judge had held the implied warranty could not cover damage caused by those pesky rats; and for the report that in August 2020 the appeals court revived the case, saying the rats had been misidentified as the problem. https://topclassactions.com/lawsuit-settlements/consumer-products/auto-news/class-action-toyota-soy-coated-wiring-attracts-vehicle-damaging-rats-can-proceed/
5. Report on the partial dismissal and continuation of the Toyota soy wiring lawsuit, published by a vehicle complaints website in 2021. Consumer news material. Source for the summary of Toyota's argument that rats and other creatures have chewed on things throughout history and that vehicles from other automakers suffer the same fate; for the plaintiffs' argument that customer complaints showed the company knew of the problem; for the description of eight customers filing a consolidated class action asserting seven state implied warranty claims and one federal warranty claim; and for the account of the district judge applying the appeals court's mandate. https://www.carcomplaints.com/news/2021/toyota-soy-wiring-lawsuit.shtml
6. Report on a Massachusetts class action against Toyota over soy wiring, published by a tyre trade magazine in 2017. Trade news material quoting the complaint. Source for the complaint's statement that soy-based materials in vehicle wiring attract rodents and other animals that nest under the hood and feast on the soy insulation and wires; for its statement that the environmentally friendly and less expensive coating is the problem and that older vehicles with non-soy insulated wires exposed to similar conditions do not experience rodent damage; for the removal of the case to federal court on the basis that more than five million dollars was likely at stake, with the named plaintiff seeking at least 17,405.36 dollars for repairs and a rental car; for the report that Kia had urged a federal judge to dismiss a similar suit because no expert evidence showed that rats even like the taste of the material; and for the report of a 2016 suit against Honda alleging that it denied defects while selling a mouse-deterring tape. https://www.tirereview.com/toyota-class-action-moves-federal-court/
7. National broadcaster's report on a 2016 breach of warranty lawsuit against Honda over soy-based wire coating. News material. Source for the account that the federal suit demanded that Honda pay for rodent damage to soy-based wiring coating adopted in an effort to go green, and for the statement attributed to the lead plaintiff that the coating costs less than plastic. https://www.nbcnews.com/business/autos/honda-s-soy-based-wiring-covers-irresistible-rodents-lawsuit-n504746
8. Article on lawsuits arising from soy-based wiring, published by a motoring website in 2024. Commercial motoring content. Source for the account that in 2016 an owner of a 2012 Accord that needed repairs twice filed a breach of warranty suit citing repairs made with rodent-deterrent tape as proof of the company's awareness, and that in 2018 an owner of a 2015 Accord filed another, both dismissed shortly afterward; for the account that the Toyota dismissal cited poor specificity and the impossibility of proving the coating attracted the animals; for the statement that Toyota had been sued multiple times without any attempt resulting in compensation or a recall; and for the characterisation of owner reports as anecdotal. https://carbuzz.com/environmentally-friendly-wiring-loom-led-to-several-embarrassing-lawsuits/
9. Article on a dismissed soy wiring case against Honda in Chicago, published by a consumer motoring website in 2025. Consumer news material. Source for the report that a named federal judge dismissed the claims; for the article's reference to a pest control company's survey ranking Chicago the most rodent-infested city; and for its description of the judicial opinion as mentioning the context of the city's rodent problem. https://mycarvoice.com/news/chicago-rats-soy-based-wiring-case-against-honda/
10. Television news report on rodent damage to vehicle wiring, published by a national broadcaster's regional service. News material quoting a pest control company employee. Source for the quoted statement by an entomologist at a pest control company that soy-based oil makes wires smell like food and serves as a gateway to other parts; and for the report that suits against several manufacturers were all dismissed, with the companies asserting they were not responsible for the rodents. https://cbsnews.com/texas/news/rats-new-cheaper-vehicle-wiring-rodents-leads-damage
11. Page listing vehicles reported to use soy-based wiring, published by a retailer of rodent deterrent products. Retail marketing material, flagged because the seller has a commercial interest in the question. Source for the account that one owner argued Honda knew of the problem as evidenced by its sale of a specialised rodent deterrent tape; for the statement that courts dismissed the lawsuits citing insufficient evidence that soy-based wiring attracted rodents more than petroleum-based wiring; and for the statement that there is no definitive scientific evidence that soy-based insulation attracts rodents more than other wire coatings. https://www.box-kat.com/blogs/box-kat-blog/full-list-of-cars-with-soy-based-wiring-2025-update
12. Article on the 2018 dismissal of a class action over rodents eating automotive wiring, published by a motoring commentary website. Commercial motoring content. Source for the account of a class action on behalf of an Indiana owner whose truck was damaged by rodents three times at an estimated total of about 1,500 dollars that the manufacturer refused to cover; for the report that the case was dismissed without leave to amend; and for the manufacturer's statement welcoming dismissal of what it called meritless claims after repeated failures to allege supporting facts. https://www.thetruthaboutcars.com/2018/07/judge-dismisses-lawsuit-over-rodents-eating-automotive-wiring/