Drivers blame the car while car makers blame the drivers. Dozens already killed and still no clear answer to what went wrong.

It seems black boxes do not sense pedal action but are installed only to record a car's performance, hence the lack of evidence as to what the driver was doing.

1 Answer 1


Unintended acceleration is a complex problem. It can be caused by hardware failures, software failures, the driver and at times even passengers.

Driver panic is a real and common cause, it is challenging for the distracted, and then, surprised to brain to react quickly and properly. It is common for the driver to believe the brake is being to pressed with natural a response to press harder... on the gas pedal. A foreign object holding the gas pedal down, whether it be the floormat or loose article, is usually a driver caused incident. This is under driver control. Blaming floormat to pedal interference was the first try in the Prius case. It is probable that it happened but was not the only cause.

Hardware causes: Stuck gas pedal, sticky accelerator cable, malfunctioning throttle actuator: These can and do happen. Proper inspection and maintenance can find most, but not all of these. This was the second try in the Prius case, it was thought that the pedal case was causing the problem, many were modified but it was not proven to be the true cause.

Software causes: Poorly written PCM code has caused this problem. This was found to be the primary problem in the Prius case. The outside experts who were allowed to review it were appalled at how poorly it was written.

Is there a black box? Not specifically. Some PCM’s can and do record data, however I know of none that make this available, or even make it known. One presumes that the OEM would use it in a legal case.

Devices are available that will record 24 hours of OBDII generic data. This data includes the throttle position information for many vehicles. Starting on or about MY 2009 This data would include all of the throttle pedal and throttle actuator data.

If a vehicle does anything I do not like I plan to turn off the power and ride out the poor braking and steering that result.

  • If it's for OEM use only, is there an easy way to make one from off the shelf parts? I was thinking of 2 possibilites:
    – Ponytell
    Dec 11, 2015 at 14:21
  • If it's for OEM use only, is there an easy way to make one from off the shelf parts? I was thinking of 2 possibilites: 1st, Raspberry Pi or Arduino (I have no experience with those). 2nd, A tiny cctv camera to view feet movement. My other concern is that I don't know if any of those will stand up in court.
    – Ponytell
    Dec 11, 2015 at 14:27
  • @Ponytell. Consider the Crecorder by Launch, it is a 24hr data recorder, or similar products. I would not know how to make such a device. The camera idea could work. What holds up in court is up to juries and judges and but some data is better than none. Anyone who has a serious unintended acceleration event should not let OEM anywhere near the vehicle and seek expert help in recovering any stored onboard data. Dec 11, 2015 at 15:56
  • While playing with the idea of a video recorder one other issue hit me: how to synchronize the clock between camera and CreRecorder. I sent an email to Launch's product support and hope to get some answers.
    – Ponytell
    Dec 13, 2015 at 10:47

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