April 5, 2023Answering 10 Common Questions about Electronic Data Recorders

FAQ's on EDR's

Previously, we published a basic overview of Data Downloads and Electronic Data Recorders (EDR). After receiving questions on the topic, we have compiled a list of your most frequently asked questions about Electronic Data Recorders (EDR).

1.      Is my vehicle downloadable?

This is our most common question!

To comply with 49 CFR Part 563 – Electronic Data Recorders, any vehicle manufactured on or after September 1, 2012, and equipped with an EDR, must have the ability to be imaged with commercially available tools.

Now for the tricky part… not all post-2012 vehicles have EDRs. So how do we know if it has data? Well, the majority of manufacturers have approved Bosch Crash Data Retrieval (CDR) as their primary tool to download the EDR data. A good reference for downloadable vehicles via Bosch is their supported vehicle list located here.

2.      What sort of data does my vehicle record?

49 CFR Part 563, outlines which data elements are required on all equipped vehicles (rather than data elements that must be reported if recorded) along with how often the data should be recorded and the accuracy of the data. Below is a chart showing the minimum required data parameters and how they should be reported.

Data ElementRecording Interval / Time
Delta-V, Longitudinal0 to 250 msec or 0 to End of Event Time plus 30 msec, whichever is shorter (100 samples per second)
Maximum Delta-V, Longitudinal0 to 300 msec or 0 to End of Event Time plus 30 msec, whichever is shorter
Time, Maximum Delta-V0 to 300 msec or 0 to End of Event Time plus 30 msec, whichever is shorter
Speed, Vehicle Indicated-5.0 to 0 sec (2 samples per second)
Engine Throttle, % Full-5.0 to 0 sec (2 samples per second)
Service Brake, On/Off-5.0 to 0 sec (2 samples per second)
Ignition Cycle, Crash-1.0 sec
Ignition Cycle, DownloadAt time of download
Safety Belt Status, Driver-1.0 sec
Frontal Airbag Warning Lamp, On/Off-1.0 sec
Frontal Airbag Deployment, Time to Deploy, DriverEvent
Frontal Airbag Deployment, Time to Deploy, Right Front PassengerEvent
Multi-event, Number of EventsEvent
Time from Event 1 and 2As needed
Complete File Recorded (Yes, No)Following other data

Other data parameters such as, but not limited to, lateral Delta-V (velocity), Engine RPM, ABS activity and steering inputs must be reported if the data is recorded.

If the vehicle is built before Sept 2012, the data reported varies between manufacturers and models.

3.      Does it record seatbelt usage?

Most passenger vehicle EDRs will show whether or not the driver and front seat passengers were belted. No EDRs, at the time of this article, record the belt status of second or third row occupants.

4.      Will it tell me if any exterior lights were on at the time of the collision?

While the EDR event will not record whether the headlights, blinkers or four-way flashers were on, other investigative methods may give more definitive answers. For example, a bulb examination may yield conclusive evidence that a bulb was incandescent or on at the time of impact.

5.      Does a destroyed vehicle still have crash data present?

It is possible! You cannot know unless you check. Our team has encountered vehicles that were burned, submerged, or repaired yield data from intact modules. There are strong caveats with each individual situation, but unless the module is confirmed to be no longer present, intact or otherwise viable, the opportunity to gather that data may have been missed.

6.      The airbags did not deploy, will there still be data available?

Possibly! Even though the airbags were not commanded to deploy, a “non-deployment” event could have been recorded. This is an event that meets the Part 563 threshold to record but the system does not decide the collision forces warrant an airbag deployment.

7.      Do all crash scenarios record an event?

Not necessarily. An airbag deployment is a telltale sign that data should be present. For a non-deployment event (post-563 vehicles), the system must see a five mile per hour change in velocity or Delta V, within 150 milliseconds (msec) to record crash-related data. If it does not deploy the airbag or meet that threshold, no data would be recorded.

8.      How do you match the download data to the subject crash?

Some Chrysler vehicles record the date and time stamp of an event and/or mileage at the event. For other vehicles, it can be determined based on ignition cycles combined with the damage to the vehicle. For example, a vehicle that was damaged beyond the drivability with 7 additional ignition cycles is a good indication that the recorded data is related to that damage. More importantly, any EDR event data must also match the facts and circumstances of the crash sequence and other investigative findings.

9.      Can the data within the EDR modules or reports be altered? Will someone get the same data if they download the vehicle after you?

For the purposes of clarity, lets separate those questions.

Can the modules or reports be altered? No. There are safeguards that a properly trained investigator uses to preserve the data. One safeguard would be to save the raw data file (.CDRx) and provide along with it any PDF copies. The raw file is not editable and can be read by anyone with the Bosch CDR software to export and verify the data within the PDF report. Furthermore, at the end of every EDR report is the hexadecimal data or raw data that was recorded and stored in the EDR.

Will someone get the same data if they download the vehicle after you? Yes, with the only difference of a possible additional ignition cycle between reports. Other than that, the crash related data will not change and cannot be removed by one investigator. The Bosch CDR tool is a read only type of tool, which is why you will normally hear investigators/reconstructionist refer to the process of imaging a module. We are taking a picture of the stored data.

10.  Is an EDR recording all the time, and does it record audio? Does it send data to the cloud?

A passenger vehicle EDR is not always recording and storing data. It also does not record audio or have cloud backup capabilities.

The system only records set parameters when one of two events are triggered: non-deployment as discussed above and deployment level. That is it. However, there are other systems now in newer vehicles that also record data that may track much more data and record longer durations if not all the time. More on that soon to come.

If you have additional questions or would like to discuss this matter further, please contact any of our qualified crash reconstructionists at Kittelson LLC.