Advanced Automatic Collision Alert (ACN) and automatic crash notification refers to a number of different systems that may call for assistance after an incident. The design and implementation of ACNs is from one manufacturer to another, but they typically use sensors in the vehicle to determine when an accident has occurred and the cellular network to call for help.
OnStar — one of the most outstanding systems that includes automatic collision alert, but bmw Assist, Toyota Safety Connect, Ford 911 Assist and other systems perform many of the same basic functions. Since the driver and passengers of the vehicle can be incapacitated after an accident, these systems are usually capable of calling emergency services if deemed necessary by the operator.
How does automatic collision alert work?
Each automatic collision notification system is slightly different, but most are linked to various sensors throughout the vehicle in addition to the vehicle’s infotainment system. The ACN typically monitors the same sensors used by the body control module to deploy the airbags, in addition to wheel speed sensors, yaw rate sensors, and more.

When certain events occur, such as a deployed airbag, the ACN takes effect. In most cases, it will use the cellular connection to communicate with the operator who will attempt to contact the driver or passengers. If no one in the vehicle responds or indicates that assistance is required, the operator can contact the emergency services and provide them with information about the accident.
In other cases, ACN will call emergency services directly after an accident. Systems with this feature typically provide the driver or passenger with the ability to cancel a call if it is accidentally triggered.
How was automatic collision alert developed?
Collision alert systems and services were 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 cell phone cdma .
Due to the large base and OnStar in the field, the Centers for Disease Control (CDC) partnered with a GM subsidiary to create the foundation for advanced automatic collision notification. The CDC convened a panel of experts that analyzed telemetry in the event of an accident, and they created a report that provides recommendations on how to use telemetry in the event of an accident 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 new vehicles that include OEM services such as OnStar, Safety Connect, or 911 Assist. Most OEMs have some form of ACN, though it is necessary to check the specific make and model of the vehicle to make sure it comes with this feature.
Many older car owners can also get ACN protection through a product like FMV OnStar. Although the FMV does not provide all the same services as a traditional OnStar, the device is able to contact the operator if it detects a failure.
Is ACN really necessary?
The main advantage of the ACN system is that it automatically calls for help. If you are unable to contact the incapacitated, or are even otherwise busy trying to help other people at the scene, the ACN system will still automatically call the telematics operator home, who will then send help if they are unable to make contact.
Without an ACN, the emergency services will not be notified in such situations until the observer calls for an emergency. In rural areas, this can result in the loss of valuable time that could cost lives.