Advanced Automatic Collision Notification

Calling For Help After a Crash When You Can't

car zaps or shocks
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Advanced automatic collision notification (ACN) and automatic crash notification refers to a number of different systems that are capable of calling for help after an accident has occurred. The design and implementation of an ACN varies from one manufacturer to the next, but they typically make use of sensors in the vehicle to determine when an accident has occurred and the cellular phone network to call for help.

OnStar is one of the most prominent systems that includes automatic collision notification, but BMW Assist, Toyota’s Safety Connect, Ford’s 911 Assist, and other systems perform many of the same basic functions. Since the driver and passengers of a vehicle may be incapacitated after a crash, these systems are typically capable of summoning emergency services if an operator determines it is necessary.

How Does Automatic Collision Notification Work?

Each automatic collision notification system is slightly different, but most of them are tied into a variety of sensors throughout the vehicle in addition to the vehicle’s infotainment system. The ACN will typically monitor the same sensors that the body control module uses to deploy the airbags, in addition to wheel speed sensors, yaw rate sensors, and more.

Automatic crash notification systems detect accidents and call for help automatically.

When specific events occur, such as a deployed airbag, the ACN springs into action. In most cases, it will use cellular phone service to connect to an operator who will attempt to communicate with the driver or passengers. If nobody in the vehicle responds, or if they indicate that assistance is required, the operator can contact emergency services and provide them with information about the accident.

In other cases, an ACN will place a call directly to emergency services after an accident has occurred. Systems with this feature typically provide the driver or passenger an option to cancel the call in case it was activated accidentally.

How Was Automatic Collision Notification Developed?

Collision notification systems and services have been independently developed by a number of original equipment manufacturers (OEMs), but OnStar was one of the first commercially available products that allowed automatic communication with an operator via a CDMA cell phone connection.

Due to the large installation base and experience of OnStar in the field, the Centers for Disease Control (CDC) partnered with the GM subsidiary to create a basis for advanced automatic collision notification. The CDC convened an expert panel that analyzed crash telemetry, and they created a report that provides advice on how to use crash telemetry to determine the likely severity of injuries and, in turn, provide more effective emergency care.

Who Can Take Advantage of Collision Notification?

The availability of automatic collision notification is limited to newer vehicles that include an OEM-specific service like OnStar, Safety Connect, or 911 Assist. Most of the OEMs now offer ACN in one form or another, though it’s necessary to check the specific make and model of a vehicle to ensure that it comes with the feature.

Owners of many older vehicles can also gain the protection of ACN by using a product like OnStar’s FMV. While FMV doesn’t provide all of the same services as traditional OnStar, the device is capable of contacting an operator if it detects a crash.

Is ACN Really Necessary?

The main benefit of an ACN system is that it calls for help automatically. If you are unable to reach your cellphone, incapacitated, or even otherwise occupied with trying to help other people at the scene of an accident, an ACN system will still automatically phone home to a telematics operator who will then dispatch help if they are unable to establish contact.

Without an ACN, emergency services would not be notified in situations like those until and unless an observer were to call in the accident. In rural areas, that can translate to the loss of valuable time that has the potential to cost lives.

According to a study performed by the National Highway Transportation Safety Administration, these systems can effectively reduce the time it takes to notify emergency services to less than a minute. Without an ACN system, the average time to notification in an urban setting is about four minutes, and about seven minutes in rural settings.

Since every minute counts when life-threatening injuries are involved, the NHTSA says that over 3,000 lives could be saved every year, just involving accidents in rural areas, if all vehicles were equipped with ACN systems.

Automatic collision and crash notification systems aren't infallible, since they rely on cellular phone service to work. That means there is a chance that even if your vehicle does have an ACN system, it may not be able to call for help in the event of an accident. But when cellular service is available, they can save lives.