Forensic Automotive Engineer Analyzes Vehicle Data to Determine Cause of Accident

This case involves a vehicle accident that occurred in a parking garage located in Wyoming. The vehicle reportedly went out of control and collided with a parking garage column and another vehicle. In the incident report, the driver stated he was driving the car when the brakes failed. At the time of inspection, the brakes were found to be functional (contrary to the driver’s statement) although the brake transmission shift interlock (BTSI) was not functioning properly. It appeared to be pinned against the floorboard at the time of the inspection. The data from the airbag control module (ACM) indicated the accelerator pedal was fully depressed prior to the collision with the parking garage column. The data from the ACM indicated that the brake pedal was not depressed at any time after engine start and prior to the collision. It also indicated that the transmission was shifted from Park to Drive while the accelerator pedal was fully depressed and the brake pedal was not depressed. This should not have been possible due to the vehicle’s brake transmission shift interlock (BTSI).

Question(s) For Expert Witness

1. Please discuss your background in forensic automotive engineering.

2. Can you determine the cause of accident by reviewing data from airbag control module or through other metrics?

Expert Witness Response E-000356

The data I need to use to determine if the accident occurred is on the brake and the brake switch. From there, I will be able to determine if the switch had been put in the on or off position, which would have been done by hitting the brake. I would also use an example car and determine at what pressure and what sense the switch would occur, and then move to the dismantled brake switch and brake pedal and see if there is damage. There is quite a bit more data I would need as well, and once I receive all of those charts, I will be able to determine what happened in this case. I do forensic accident reconstruction for a living, and have worked on similar cases as an expert witness, too. However, possible ruined brake switches are rare cases, but I do have the expertise in knowing how they work and will be able to better assess this scenario given my professional experience.