What Vehicle Defects Cause the Most Car Accidents?

According to the National Highway Traffic Safety Administration (NHTSA), tire problems play a role in more car accidents than any other mechanical issue. This can mean more than normal wear and tear, too. Some tire defects are baked in when manufactured, including:

• Tread separation: This happens when the outer layer of the tire peels away from the underlying casing. This tends to happen at highway speed, when heat and friction stress the bond between layers. When the tread separates, the driver can lose control of the vehicle almost immediately.
• Sidewall defects: Weak spots in the sidewall of the tire can cause it to rupture without warning. These defects are often the result of improper curing or poor materials used during manufacturing. This kind of defect is usually not visible to the driver during routine inspections.
• Bead failures: The bead is the part of the tire that seats against the wheel rim. When a bead is defective, the tire can separate from the rim entirely, which at any speed is likely to cause the driver to lose control.

Because these defects originate during the manufacturing process, entire production runs can be affected. Tire recalls are common for vehicles.

Brake problems are the second most commonly cited vehicle issue in car accident data, behind tires. Brake defects can occur suddenly in a system that appeared to be working fine. For example:

• The master cylinder converts pressure from the brake pedal into hydraulic force. When it fails, pressing the brake pedal may produce little or no response.
• Hydraulic brake lines carry pressurized fluid from the master cylinder to the brake calipers. A defective line can leak or rupture, causing a partial or complete loss of braking power with no warning.
• A defective anti-lock braking system (ABS) can cause the brakes to lock up unexpectedly or fail to engage properly, especially during hard braking when the system is needed most.

Unlike worn brakes, which give a driver time to recognize the problem and act, a defective brake system can go unnoticed until disaster strikes.

When your steering or suspension fails, you can struggle to steer your vehicle or lose control altogether. Common defects include:

• Tie rod failures: Tie rods connect the steering system to the wheels. A defective tie rod can snap without warning, causing the driver to lose control.
• Power steering failures: A defective power steering pump or rack can make the steering wheel suddenly stiff or unresponsive.
• Suspension component failures: Defective control arms, ball joints, or struts can cause a wheel to collapse or separate from the vehicle.

In extreme cases, these defects can lead to a rollover, especially for SUVs and trucks.

Modern vehicles rely on electrical systems to control everything from the engine and transmission to the brakes and steering. When a defect disrupts those systems, it can cripple your vehicle and lead to an accident.

The GM ignition switch scandal is a prominent example of a power defect. Before it was fixed, GM ignitions could slip out of the "run" position while the vehicle was in motion. Power was simultaneously cut to the engine, power steering, power brakes, and airbags. GM was aware of the defect for over a decade before recalling more than 30 million vehicles. 

Beyond ignition switches, electrical defects can include:

• Faulty wiring, which can cause short circuits and turn off critical systems.
• Electronic control unit (ECU) defects, which can result in erratic vehicle behavior, including sudden stalling.
• Battery and charging system failures, which can shut down power to a vehicle mid-drive.

Unintended acceleration happens when a vehicle speeds up without the driver pressing on the gas or when the pedal sticks and won’t return to a resting position. Either way, it can be terrifying when a runaway vehicle careens toward other vehicles or stationary objects without giving the driver time to stop.

These failures often stem from a defect in the throttle body or an error in the electronic throttle control system. Sometimes, it’s as simple as a floor mat pinning the pedal down. Regardless, manufacturers often bear the blame for this defect. In 2009 and 2010, Toyota recalled millions of vehicles for unintended acceleration. By then, the defect had already led to hundreds of injuries.

Defective headlights may not produce enough light to illuminate the road adequately, or they may fail without warning. A driver with defective headlights may not spot danger in time to stop. Defective taillights and brake lights can make a car or truck nearly invisible to following vehicles, increasing the risk of a rear-end collision. Several factors can cause a lighting defect, including:

• Faulty wiring
• Bad connectors
• Faulty bulbs or lenses

A vehicle can pass a visual inspection and still have a dangerous lighting failure waiting to happen.

Fuel system defects can cause accidents in two very different ways.

• A defective fuel pump or fuel injector can cause the engine to stall without warning, leaving a driver without power at highway speed.
• A fuel line leak or rupture creates a fire risk that can turn even a minor collision into a fiery scenario.

Both types of failure may stem from manufacturing defects in components that are not accessible during routine maintenance, which means a driver may not know anything is wrong until the system fails.

Vehicle defects can qualify as grounds for a lawsuit. When companies design or sell a defective vehicle part, they can be held responsible for resulting crashes. These defects generally fall into three categories:

1. Design defects: The product was designed in a way that makes it inherently unsafe, even when manufactured correctly.
2. Manufacturing defects: The design was sound, but something went wrong during the production process, resulting in a flawed product.
3. Failure to warn: The manufacturer knew about a risk associated with the product but did not adequately warn consumers.

Any of these can form the basis of a product liability claim. In most cases, an injured person does not have to prove that the manufacturer was negligent. Instead, they need to show that the product was defective and that the defect caused their injury.

If you were in a car accident and suspect a vehicle defect played a role, the SiebenCarey team can help you understand your options. Contact us today for a free consultation.