Last updated: July 2026
Car, truck, and motorcycle crashes aren’t always caused by a driver’s mistake. Sometimes the vehicle itself failed. A defective tire, a seat belt that doesn’t hold, an airbag that shouldn’t have deployed, or that should have and didn’t.
Some manufacturers have known about a defect and done little to fix it before it reached the road. When that happens, liability isn’t limited to the other driver; it can extend to the manufacturer, a parts supplier, or the shop that installed a defective replacement part.
Vehicle defects generally fall into two categories: design flaws, where the vehicle was never engineered to be safe in the first place, and manufacturing defects, where the design was sound but something went wrong in production. Either can lead to serious injury or death.
Common Types of Auto Product Defects
Defective Tires
Tires that age faster than they should, are built with substandard materials, or have a hazardous design can blow out or fail. Manufacturers aren’t the only ones who can be liable here: a repair shop that sells old tires as new, or installs the wrong tire for the vehicle, can share responsibility too.
Seat Belt Defects
Seat belts reduce the risk of moderate-to-critical injury by up to 50% and the risk of a fatal injury by roughly 45%, according to NHTSA. Illinois requires children under 8 to be secured in an appropriate child restraint system, and everyone 8 and older, in any seat, to wear a seat belt. When a manufacturing defect keeps a belt from locking or holding as designed, that protection disappears exactly when it’s needed most.
Seat Belt Submarining
This happens when an occupant slides underneath the lap portion of the belt during a sudden deceleration, usually because the seat cushion or belt geometry wasn’t designed properly. It’s a design issue, not user error.
Defective Airbags
Federal law requires frontal airbags for the driver and front passenger in every new vehicle; side and curtain airbags, while common, aren’t federally mandated. When a manufacturing defect causes an airbag to deploy improperly, fail to deploy, or discharge shrapnel or hazardous gas, the injuries can be severe. Counterfeit replacement airbags installed during repairs have caused some of the most serious documented cases.
Uncontrolled Acceleration
This is when a vehicle accelerates without the driver’s input, often tied to software or electronic throttle control issues in modern vehicles. Toyota’s high-profile Prius and other model recalls over unintended acceleration complaints remain one of the most widely documented examples of this defect type.
Defective Power Windows
Power windows are standard on virtually every vehicle sold today, and defects in their mechanisms have caused serious injuries, particularly to children.
Proving an Auto Defect Claim
Your attorney has to connect the defect to your injury. Sometimes that link is obvious, an airbag that never deployed in a head-on collision resulting in facial and brain trauma. Other times it requires an expert to examine the vehicle and establish the connection. Either way, you may be entitled to compensation for medical bills, lost wages, future medical costs, and pain and suffering.
If more than one party contributed to your injury, Illinois’ comparative negligence rule still allows you to recover even if you were partially at fault, as long as your share is 50% or less.
Frequently Asked Questions
Who can be held liable for a defective auto part?
The vehicle manufacturer, the parts manufacturer, or a repair shop that installed a defective or counterfeit part can all potentially be liable, depending on where the defect originated.
Are all cars required to have side airbags?
No. Federal law only requires frontal airbags for the driver and front passenger. Side and curtain airbags are common but not federally mandated.
What’s the difference between a design defect and a manufacturing defect?
A design defect means the vehicle was never engineered to be safe. A manufacturing defect means the design was sound, but something went wrong in production of that specific unit or part.
Can I recover compensation if I was partially at fault for my accident?
Yes, as long as you’re 50% or less at fault under Illinois’ comparative negligence rule. Your award is reduced by your percentage of fault.
Contact Our Auto Product Liability Attorneys
The Illinois personal injury law firm of Phillips Law Offices has a recognized reputation as having aggressive, skilled, and determined representatives and advocates for injured individuals and their families. Our Chicago product liability lawyers handle auto defect cases on a contingency basis: no upfront fee, nothing owed unless we win. Contact us at (312) 346-4262 for a free consultation.
Read More:
