In 2009, a Lexus suddenly started speeding on a California highway. The driver, off-duty police officer Mark Saylor, called 911.
“We can’t stop… we’re going 120…”
Moments later, the car crashed. Everyone inside was killed.
At first, Toyota blamed floor mats and driver error. But more reports came in: cars that accelerated by themselves, brakes that didn’t respond, and no clear signs of failure in the data.
The reality was more complicated. Inside modern cars, computers control almost everything: speed, brakes and sensors. A small software bug in one system can affect the others.
Investigators found that even tiny faults in Toyota’s code could cause dangerous results. One mistake could lock up the CPU, disable safety checks, and make the car ignore brake commands.
This wasn’t just a mechanical problem. It was a software failure, one that showed how invisible code can turn deadly when design, testing, and safety don’t align.
What engineers can learn:
- Hardware isn’t perfect, software must be ready for it to fail.
- Safety systems need multiple layers, not just one check.
- Testing culture is important as much as the code itself.
- Small logic bugs can lead to big real-world disasters.
You can read the full story, including technical details, investigations and lessons, here:
The Car That Would Not Stop
Top comments (1)
Just wait until all that very sensitive, life threatening code is AI written & no one really knows how it works. 😵💫