Defective Vehicle Parts and Car Accidents in Wisconsin: When the Manufacturer May Be Liable

Most people walk away from a crash assuming the other driver caused it. But when defective vehicle parts cause a car accident, or turn an ordinary collision into a catastrophic one, the real responsibility may sit with a manufacturer, not a driver. Airbags that never fired. Brakes that went soft at the worst possible moment. A tire that came apart at highway speed on I-94. If something about your Wisconsin crash felt wrong, trust that instinct. At Badger Injury Law, we investigate the vehicle itself, not just the police report.

A Car Accident Is Not Always the Driver's Fault

Police crash reports are built to document driver behavior. There is a box for speed, a box for alcohol, a box for failure to yield. There is no box for a corroded brake line, a crash sensor that never sent the deployment signal, or a tire that separated from the inside out. Once an officer identifies a driver-side explanation, the investigation usually stops there.

Ours does not. Certain patterns tell us the vehicle deserves a hard look: the car behaved strangely in the seconds before impact (the brakes did not respond, the steering pulled, the vehicle accelerated on its own), the safety systems failed during the crash (airbags, seat belts, seatbacks, roof structure), or the injuries were far more severe than the visible damage would predict. Our Milwaukee car accident lawyers treat every serious crash as a case where the obvious explanation might not be the whole explanation.

There is a practical reason this matters. When the at-fault driver carries a minimum-limits insurance policy, your recovery can be capped far below your actual losses. A product liability claim may provide another avenue for recovery when a defective component contributed to your injuries. Identifying all potentially responsible parties is an important part of evaluating the full scope of a case. Finding that claim, when it exists, can change everything about what your case is worth.

The Three Types of Vehicle Defects Under Wisconsin Product Liability Law

Wisconsin product liability law is set out in Wis. Stat. § 895.047. Under the statute, a product like a vehicle or a vehicle component can be legally defective in three ways, and each one shows up differently in a crash.

1. Manufacturing Defects

A manufacturing defect means the product departed from its intended design, even though all possible care was exercised in making it. In plain terms: the design was fine, but your unit was not. A weld that did not hold. An airbag inflator seated incorrectly on the line. A batch of brake components with contaminated material. The rest of the model year may be perfectly safe while the part in your vehicle was flawed from the day it was built.

2. Design Defects

A design defect means the entire product line is dangerous as designed. Wisconsin sets a demanding standard here: a design is defective only if the foreseeable risks of harm could have been reduced or avoided by a reasonable alternative design, and skipping that alternative made the product not reasonably safe. When Wisconsin overhauled its product liability law in 2011, it replaced the older consumer-expectations approach with this stricter test and made these claims harder to win.

We tell clients this up front because it explains how these cases have to be built. Proving a design defect requires strong technical evidence, including engineering analysis, testing, and documentation showing that a safer, practical alternative design was available: show the safer design that existed, show it was practical, and show the company chose not to use it. That is not a case you build with a demand letter. It is a case you build with engineers, testing data, and internal company documents, which is exactly how we build them.

3. Inadequate Instructions or Warnings

The third category covers products that are dangerous because of what the manufacturer failed to say. If foreseeable risks could have been reduced by reasonable instructions or warnings and the manufacturer left them out, the product can be defective on that basis alone. In vehicle cases, this often looks like a known stalling or fire risk the company downplayed, or recall notices that went out late, went to the wrong addresses, or buried the danger in fine print.

Wisconsin's 15-Year Rule: The First Question in Every Defective Part Case

This rule matters more in Wisconsin than almost anywhere else, because our vehicles are old. Salt-belt cars and trucks stay on the road for decades, and a large share of the vehicles involved in Wisconsin crashes were built more than 15 years ago. We will tell you honestly and quickly if the 15-year rule limits your options. But do not rule yourself out at the kitchen table. The 15-year bar applies to strict liability claims under the statute; depending on the facts, other legal theories, or claims against parties other than the original manufacturer, may still be available. The age of your vehicle is a question for your lawyer, not a reason to skip the phone call.

What If My Airbags Didn't Deploy?

This is the defect question we hear more than any other, and the one surrounded by the most confusion. If you were hurt in a crash and your airbags never fired, here are straight answers.

Why Didn't My Airbags Deploy?

Start with an uncomfortable truth: airbags are not designed to deploy in every crash. Frontal airbags are engineered to fire in moderate to severe frontal impacts, and there are legitimate reasons a system stays quiet: the impact fell below the deployment threshold, the crash forces came from an angle or direction the front airbags do not cover, or occupant sensors classified the seat in a way that suppressed deployment. Non-deployment is not automatically a defect, and any lawyer who tells you otherwise before examining the vehicle is guessing.

But there are also failure reasons that point straight at a defect: crash sensors that malfunctioned or were mounted where they could not detect the impact, corroded or damaged wiring harnesses, a defective airbag control module, software and calibration errors, or a prior repair where the system was never properly restored, sometimes with counterfeit parts. The only way to know which category your crash falls into is a professional inspection, including a download of the vehicle's event data recorder. That module records speed, deceleration forces, belt status, and whether the system commanded a deployment. It answers the question. It is also lost forever if the vehicle is repaired or scrapped first.

Airbags Didn't Deploy in a Front-End Collision: Is That a Defect?

A front-end collision is exactly the crash frontal airbags exist for, so non-deployment in a significant frontal impact deserves real scrutiny. It is still not automatic. Deployment depends on the severity and angle of the impact, and offset or underride collisions can produce serious injuries at force patterns the sensors read differently. Here is the practical screen we use: a meaningful frontal impact, serious injuries, and no deployment. If your crash checks those three boxes, the airbag system should be examined by an engineer before anyone accepts the insurance company's version of events.

Can You File a Lawsuit If Your Airbags Didn't Deploy?

Yes, when the evidence supports it. An airbag non-deployment lawsuit generally requires proving three things: the airbag system was defective, the defect existed when the vehicle or part left the manufacturer's control, and the failure to deploy caused injuries beyond what you would have suffered in the crash anyway. That last element matters. The airbag did not cause the collision; the claim is that it failed to protect you the way it was designed and marketed to. These are technical cases, they are fought hard, and not every non-deployment becomes one. We will tell you which kind yours is after we look, not before.

Is There a Typical Airbag Non-Deployment Lawsuit Settlement?

No, and be careful with anyone who quotes you a number before investigating your case. Airbag non-deployment settlements depend on the severity of your injuries, what the medical evidence says deployment would have prevented, the strength of the engineering findings, and which defendants are on the other side of the table. What we can tell you is structural: these claims are pursued against manufacturers and their insurers, not against a single driver's policy limits, so when the evidence holds up, the full value of your losses is on the table. Every case is different, and past results never guarantee a future outcome.

If a large-scale airbag defect sounds far-fetched, remember Takata. The National Highway Traffic Safety Administration calls the Takata airbag recalls the largest and most complex vehicle recalls in United States history: roughly 67 million airbags under recall, with 28 confirmed deaths in the U.S. tied to rupturing inflators. Airbag defects are not a hypothetical. They are the biggest recall story the auto industry has ever produced.

Common Defective Vehicle Parts That Cause Car Accidents

Airbags get the headlines, but almost any critical system can fail because of a defect. These are some of the most common defective components in serious crashes:

• Brakes. Corrosion-prone brake lines, failed master cylinders, defective calipers, and faulty ABS modules can leave a driver pressing a pedal that does nothing.
• Tires. Tread separation and sidewall blowouts at highway speed cause instant loss of control. Defects can come from the factory or from aged "new" tires that sat in storage for years before they were sold.
• Steering and suspension. Tie rods, ball joints, and control arms that fracture or separate can take steering authority away without warning.
• Fuel systems. Tank placement and fuel line designs that rupture in otherwise survivable collisions can turn a crash into a fire. When a fuel-fed fire turns a collision fatal, the family may have a wrongful death claim against the manufacturer as well as any at-fault driver.
• Seat belts and seats. Buckles that unlatch on impact, webbing that tears, and seatbacks that collapse rearward defeat the very systems meant to keep you alive.
• Electronics and software. Unintended acceleration, throttle faults, sudden stalling in traffic, and sensor failures are increasingly the defect stories of modern vehicles.

Defective Parts on Commercial Trucks and Semis

When an 80,000-pound truck loses its brakes, its coupling, or a retread at highway speed, the consequences fall on everyone around it. Commercial vehicle cases add a layer of complexity: the failure might trace to a defective component, to a trucking company that skipped maintenance, or to a rebuilder who put a substandard part back into service. Those are different defendants with different insurance, and sorting out which one answers for the failure is central to the case. Our truck accident lawyers investigate the equipment, the maintenance records, and the supply chain behind the part, not just the driver's logbook.

Road Salt, Rust, and Potholes: How Wisconsin Winters Factor Into Defect Claims

Wisconsin is one of the hardest places in America to be a car. Road salt and de-icing brine attack brake lines, fuel lines, subframes, and suspension mounts from November through April. Freeze-thaw cycles tear the pavement apart, and the potholes that follow hammer tires, wheels, and suspension components mile after mile. Parts fail here that would last years longer somewhere warm and dry.

Here is the honest part, because it is also the strategic part: corrosion alone is not a defect. Federal regulators spent years investigating rusted brake lines in older salt-belt trucks and closed the investigation without ordering a recall, concluding the corrosion was wear from salt exposure rather than a manufacturing or design flaw. You can be certain the manufacturer's defense team knows that outcome and will argue your part simply wore out. The questions that actually decide these cases are different ones: Was the part designed and coated for the environment it was sold into? Did it corrode dramatically faster than comparable designs? Did the manufacturer know about premature failures and stay quiet? Was the component ever the subject of a recall or investigation? Answering those questions takes engineering analysis and manufacturer records. It is precisely the work a defense team hopes you never do.

The Crashworthiness Doctrine: When the Crash Was Survivable but the Injuries Were Not

Some of the most important defect cases start with a question a grieving family asks: how did a crash like that cause injuries like these? The legal answer is the crashworthiness doctrine, sometimes called the second collision or enhanced injury rule, and Wisconsin courts have recognized these claims for decades. The idea is simple: manufacturers must design vehicles to reasonably protect the people inside when a crash happens, because crashes are foreseeable. When a defect makes injuries worse than the collision itself should have caused, the manufacturer can be held responsible for that added harm, even though it did not cause the crash.

Crashworthiness failures include roofs that crush in rollovers, seatbacks that collapse into rear passengers, airbags that never deploy, door latches that open on impact, and fuel systems that ignite. The injury patterns are catastrophic: when a moderate collision produces a severe traumatic brain injury, a spinal cord injury, or a death that the crash forces alone do not explain, the vehicle's performance deserves scrutiny. Practically, this means you can pursue two claims at once: one against the driver who caused the collision, and one against the manufacturer whose defect turned a survivable crash into a life-changing one.

Who Can Be Held Liable for a Defective Vehicle Part in Wisconsin?

Depending on the facts, responsibility for a defective part can reach several parties: the vehicle manufacturer, the company that made the specific component (an inflator, a tire, a brake assembly), and in limited circumstances under Wisconsin law, the sellers and distributors who put the product into the market. When the real problem was a botched repair or the wrong replacement part, a repair shop or installer can be liable under ordinary negligence instead. Identifying every responsible party is not academic. It is how a claim limited by one driver's insurance policy becomes a case with defendants actually capable of paying for a lifetime of consequences.

What If I Was Partly at Fault for the Crash?

You can still have a case. Wisconsin follows a comparative negligence system, and for product liability claims the specific rule is in Wis. Stat. § 895.045(3). In plain terms: you can recover on a product claim as long as your share of responsibility is not greater than the share caused by the defect, and your award is reduced by your percentage of responsibility. If you are found 20 percent responsible, your compensation is reduced by 20 percent.

Expect the manufacturer to lean on this. Their playbook in defect cases is to shift fault anywhere else: you were speeding, you missed an oil change, you ignored a dashboard light, the road was bad. Some of that may even be partly true, and it still does not erase a defect claim. Our job is to keep the jury's eyes on the part that failed and to make sure your share of fault is argued down to what the evidence actually supports, not what the defense wishes it were.

Punitive Damages in Wisconsin Defective Part Cases

Punitive damages exist to punish and deter truly egregious conduct, and Wisconsin reserves them for exactly that. Under Wis. Stat. § 895.043, a jury can award punitive damages only on evidence that the defendant acted maliciously or in intentional disregard of the plaintiff's rights, and Wisconsin generally caps the award at twice the compensatory damages or $200,000, whichever is greater. In a defect case, that standard usually means documents: internal testing, warranty data, or memos showing the company knew about the danger and kept selling anyway. Most defective part cases resolve on compensatory damages, the money that covers your actual losses. When the paper trail shows a company choosing profit over the people in its vehicles, we pursue punitive damages too. We just will not promise them to get you in the door.

What to Do If You Think a Defective Part Caused Your Accident

1. Preserve the vehicle. This is everything. Notify your insurer in writing that the vehicle is evidence and must not be repaired, altered, or sent to salvage. Do not sign a release transferring it. If it has already been towed to a salvage yard, call a lawyer immediately; vehicles can sometimes be located and secured if you move fast.
2. Check your VIN for recalls. Run your vehicle identification number through NHTSA's free recall lookup at nhtsa.gov/recalls. An open recall on the failed system is powerful information. No recall does not mean no defect, and a recall alone does not prove your case, but either way your lawyer needs to know.
3. Photograph everything. The vehicle inside and out, the specific part if it is visible, the crash scene, and your injuries.
4. Get medical care and follow through. Your health comes first, and consistent treatment records also document what the failure cost you.
5. Gather your paperwork. Maintenance and repair records, purchase documents, and any recall notices you received. These records defeat the "you neglected the car" defense before it starts.
6. Do not give recorded statements. Not to the other driver's insurer, and not to anyone calling on behalf of a manufacturer, before you have spoken with your lawyer.
7. Call early. Evidence disappears, salvage timelines are short, and Wisconsin's filing deadlines run whether or not you have answers yet.

How Badger Injury Law Investigates Defective Vehicle Part Cases

Defect cases are won with evidence most crash victims never know exists. Securing and inspecting the vehicle before it disappears. Downloading the event data recorder. Retaining mechanical and electrical engineers who can testify about how the part failed and what a reasonable alternative design looked like. Mining NHTSA's recall, investigation, and consumer complaint databases for the failure pattern. Forcing the manufacturer, through discovery, to hand over the internal testing and warranty records it never wanted a jury to see.

Manufacturers take these cases seriously, because one adverse verdict can invite thousands of claims. The moment yours looks credible, a national defense firm will be working on it. These cases require careful preparation, experienced legal guidance, and access to qualified experts who can evaluate what happened. Badger Injury Law handles these cases on a contingency fee, so you pay no fee unless we recover for you. The firm is led by trial attorney Jared Powell, who built his career taking on powerful insurance companies. Learn more about our team and how we work.

The Badger Never Backs Down

Manufacturers and insurance companies will closely examine the evidence in these cases. Having the vehicle properly preserved and the failure independently investigated can make an important difference. That is not how we operate. If your crash was worse than it should have been, if a safety system failed you, or if your vehicle did something no vehicle should do, we will dig until we know why, and we will tell you the truth about what we find, including when the honest answer is that you do not have a defect case.

Frequently Asked Questions About Defective Vehicle Parts and Car Accidents

How do I know if a defective vehicle part caused my car accident?

Watch for four signals: the vehicle behaved abnormally before the crash, a safety system failed during it, your injuries were out of proportion to the visible damage, or the failed system appears in a recall when you check your VIN at nhtsa.gov/recalls. None of these proves a defect on its own. Confirming one requires a professional inspection of the vehicle, which is why preserving it matters and why we arrange that inspection as part of building the case.

What should I do if my airbags didn't deploy in my accident?

Preserve the vehicle before it is repaired or salvaged, get medical care, and have the airbag system and event data recorder examined by a qualified professional. Airbags are not designed to deploy in every crash, so non-deployment is not automatically a defect. But if you suffered serious injuries in a significant frontal impact and the airbags stayed quiet, that combination warrants a real investigation, not an adjuster's shrug.

Can I sue the manufacturer if another driver caused the crash?

Yes. Under the crashworthiness doctrine recognized in Wisconsin, a manufacturer can be held responsible for injuries a defect made worse, even though the defect did not cause the collision itself. In practice, that means a claim against the at-fault driver and a separate claim against the manufacturer can proceed together, with each defendant answering for the harm it caused.

What compensation can I recover in a Wisconsin defective vehicle part case?

Compensation can include current and future medical expenses, lost income and reduced earning capacity, pain and suffering, and property damage. Families who lose a loved one may recover wrongful death damages. In limited cases involving malicious conduct or intentional disregard for safety, Wisconsin law allows punitive damages, subject to the statutory cap. Every case is different, and no attorney can guarantee a particular result.

How long do I have to file a defective vehicle part claim in Wisconsin?

Several clocks matter. First, Wisconsin generally gives you three years from the date of injury to file a personal injury claim. If the crash caused a death, the wrongful death claim must be filed within two years of the date of death under Wis. Stat. § 893.54(2m). Second, Wisconsin's product liability statute generally bars strict liability claims when the product was manufactured 15 or more years before the claim accrues, with limited exceptions. An older vehicle does not automatically end the conversation, but it makes the conversation urgent. Call early so we can evaluate every deadline and every available legal theory before options close.

Should I keep my damaged vehicle after the crash?

Yes, or at minimum make sure it is preserved where it sits. The vehicle is the central piece of evidence in any defect claim: the failed part, the crash sensors, and the event data recorder are all inside it. Notify your insurer in writing not to dispose of it and do not authorize repairs until it has been inspected. If it has already gone to salvage, call us immediately; acting within days can be the difference between recovering the evidence and losing it.

Results may vary and depend on your particular facts and legal circumstances. Prior results do not guarantee a similar outcome. This article is for general informational purposes only and is not legal advice.