Heavy Vehicle Event Data Retrieval
Heavy Vehicle Event Data Retrieval (HVEDR)- Downloads Available on the Following:
ENGINE
- Caterpillar
- Detroit Diesel
- International
- Cummins
- Mercedes Benz
- Paccar (Kenworth – Peterbilt)
- Mack
- Volvo
BRAKES
- Bendix
- WABCO
- Haldex
Safety Systems
- OnGuard
- Detroit Assurance
- Wingman
Heavy Vehicle Event Data Retrieval (HVEDR)
Engine Control Modules, Air Bag Control Modules and Crash Data Recorders
Electronic controls were introduced into small trucks and automobiles to monitor the vehicle accelerations and analyze the data to determine when an accident is occurring and whether it is serious enough to deploy the airbags. The time frame to accomplish this is very short, on the order of 25 milliseconds. These modules may continue to monitor the accelerations after the deployment of the airbag.
Typical Stopping Decelerations for Hard Braking/Skidding & Low Speed Accelerations (PDF)
Airbag Control Modules (ACM)
Electronic controls were introduced into consumer trucks and automobiles to monitor the vehicle accelerations and analyze the data to determine when an accident is occurring and whether it is serious enough to deploy the airbags. The time frame to accomplish this is very short, on the order of 25 milliseconds. These modules may continue to monitor the accelerations after the deployment of the airbag.
Typically record:
- Seat belt status
- Longitudinal collision accelerations/delta v
- Airbag faults if present
May record:
- Speed, RPM, throttle, braking before collision
- Lateral collision accelerations/delta v
- Multiple events
- May capture data from event even if the airbags did not deploy
- Other parameters
ACM, PCM, ROS
ECM – Engine Control Modules
Caterpillar Detroit Diesel International Cummins Mack Volvo Mercedes Benz Paccar (Kenworth – Peterbilt)
Electronics were introduced into the heavy truck engines to control emissions, the engine, the powertrain, and monitor the status of the primary engine operations primarily for maintenance purposes. Some of the functions such as speed, rpm, throttle and brake status are directly applicable to the analysis and reconstruction of an accident.
Heavy truck engine manufacturers use different terminology for their particular module(s). MCM, VECU, ECU etc. All refer to the same basic components. Some manufacturers use a single module bolted to the engine. Others use two or three separate units. These can be located on the engine, frame or in the cab. Multiple units are typically split with one on the engine and the others in the cab.
Software/Hardware
- Every manufacturer uses their own proprietary software.
- In cab connections are standardized (6 pin or 9 pin) but may require separate hardware to access
- Direct to ECM connections require separate cables and other hardware
- Will provide large amounts of data on the engine and its operation.
- May provide information on speed, RPM, braking, throttle, etc. before, during and after the collision.
- Speed data comes from the VSS (vehicle speed sensor) that monitors the drive shaft rotation.
Decisions to be made with respect to altering the ECM Data after an Accident
- Should the vehicle be moved under its own power?
- Should a download be attempted on a damaged vehicle? If so how?
- Does downloading alter the data?
- Can the module be removed to preserve the data?
Powertrain Control Modules
Automobiles and small trucks typically have an electronic module that controls the powertrain. These are similar in size and function to the heavy truck ECM. Some of these modules may record and retain data.
Rollover Sensors (ROS)
Electronic controls were introduced into vehicles to monitor lateral accelerations for both side airbag deployment and stability control. Some of this data may be captured and available for download. Stability control is standard in newer small vehicles and is increasingly present in heavy trucks.
ROS in automobiles is accessed with the CDR system. In heavy trucks, ROS is typically associated with the stability control and is part of the braking system.
Event Data Recorders (CDR)
- Other types of devices may provide information
- Vorad collision avoidance and warning
- Wingman
- GPS tracking
- ABS brake systems
- PeopleNet
- QualComm
- EasyPass
- Electronic Logbook
- VORAD (Vehicle Onboard Radar)
- Collision Avoidance and Warning
- OnGuard Collision Avoidance
- Detroit Assurance Safety Systems
- Bendix Wingman
Heavy Vehicle Event Data Retrieval (HVEDR)
Electronics were introduced into heavy truck engines to control emissions, the powertrain, and monitor the status of engine operations. Some of the functions such as speed, rpm, throttle and brake status are directly applicable to the analysis and reconstruction of an accident.
The name plate on the truck e.g. Freightliner, Volvo, Kenworth, etc. does not identify the engine. If unknown, the engine can be determined from the 17 digit VIN (Vehicle Identification Number). Caterpillar, Cummins, Detroit Diesel, International, Mack, Volvo, and Mercedes Benz are the major engine manufacturers.
Commercial vehicle truck engine manufacturers use different terminology for their particular module(s). MCM, VECU, ECU etc. All refer to the same basic components. Some manufacturers use a single module bolted to the engine. Others use two or even three separate units. These can be located on the engine, frame or in the cab.
There are decisions to be made with respect to “altering” the ECM Data after an Accident.
- Should the vehicle be moved under its own power?
- Should power be removed?
- If the vehicle has already been driven after the accident , does it matter?
- Should a download be attempted on a heavily damaged vehicle? If so how?
- Can the appropriate circuits be repaired?
- Can the module be removed and downloaded?
- Does downloading alter the data?
- Can the module be removed to preserve the data?
The answers vary depending on a) the particular truck and ECM, b) the type of crash and c) what happened to the vehicle/engine during and following the accident.
Many commercial vehicles have other electronics that should also be considered.
- Is there data in the ABS, Stability Control, Collision Avoidance or other safety systems?
- Does the truck have an airbag system?
- Does the truck have a GPS unit and if so what type?
- Does the truck have electronic logs, Qualcomm or a similar system
- Does the truck have any collision avoidance systems?
- Does the trailer have any electronic systems? If so what type?