Rodents Can’t Get Enough of Toyota’s Soy Wire Coating

Somewhere in the mid-2000's there was an industry-wide push by automakers to replace plastic and glass-based wiring insulation with a more eco-friendly soy-based coating. It's biodegradable, commendable, and a complete disaster for owners. Yeah, you heard me.

Don’t get me wrong, the idea is great. Unfortunately rodents also think its great because the biodegrabable material is easier to chew and is an abundant nesting material.

The resulting damage can cost owners anywhere between $2,000 and $9,000. It’s a huge tab and if you’re thinking Toyota will pick it up, think again. Owners say Toyota denies any rodent-related warranty claims to the electrical system because its classified under “other environmental conditions” in their express warranty.

The warranty specifically excludes damage from “[a]irbone chemicals, tree sap, road debris (including stone chips), rail dust, hail, floods, wind storms, lightning and other environmental conditions.”

Wasn’t it Toyota’s decision to change the environemnt?

Soy-Based Wiring Lawsuits

The soy-based wire coatings were the subject of a lawsuit that was filed back in December of 2016.

In Heidi Browder vs. Toyota Motor Corporation the plaintiff argued that Toyota knows about the problem but does nothing to help fix it.

According to the plaintiff, she learned the hard way about the soy wiring when her Avalon wouldn’t start and a look under the hood showed wires chewed, so she had the car towed to a dealer. Toyota told her rodents had caused the damage and it would be no problem to repair the problems as long as she could cough up $6,000 to cover the bill.

A year later another class-action lawsuit, Roscoe v. Toyota Motor Sales USA Inc., was filed in Massachusetts.

When [a plaintiff] brought his Toyota Sequoia to the dealership for a routine oil change on December 8, 2016, he allegedly learned mice had caused extensive damage to the truck. The mice had chewed through so much of the wiring the dealership allegedly told him to immediately stop driving the truck because it could catch fire.

Both lawsuits argue that Toyota violated fraud and consumer protection laws because they know the new wiring attracts roents, but even damaged wiring is replaced with the same problematic coating.

Ultimately, it ends up substantially increasing the costs associated with owning a Toyota.

One case dismissed, others soon to follow?

A third lawsuit was dismissed by a judge in June of 2018. The judge ruled many arguments in favor of Toyota, starting with the platintiffs using competing arguments as to why rodents eat the wires.

“Considering this considerable variance, it isn’t clear that Toyota could have specifically articulated any increased “risk” to any particular part of Plaintiffs’ vehicles because of the soy coated wiring.” - Judge Andrew Guilford

Toyota argued that rodents were a problem long before switching to soy-based wiring and that one plaintiff’s pointing out they had mice in their cabin is “entirely consistent with the idea that something other than insulation might explain these plaintiffs’ various rodent encounters.”

The judge agreed that the arguments are a stretch.

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.

The dismissal of Albert Heber v. Toyota Motor Sales U.S.A., et al. may be bad news for the other pending cases.

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