The NHTSA Office of Defects Investigation (NHTSA) has opened two separate investigations related to unexpected breaking in certain Honda and Tesla vehicles. These vehicles are equipped with collision mitigation braking systems (CMBS) or advanced driver assistance systems (ADAS), which visually and audibly alert the drivers of a potential collision. Under certain circumstances, the system will automatically apply the brakes to help reduce the force of an unavoidable collision.
The problem of unexpected braking has been called “Phantom Braking”. Phantom braking is when a vehicle’s brakes activate unexpectedly even when traffic is flowing normally or there is no obstacle to avoid.
Inadvertent Automatic Emergency Braking
2017-2019 Honda CR-V and 2018-2019 Honda Accord
NHTSA Investigation Number: PE22003
The NHTSA has received a total of 278 complaints and several Early Warning Reports alleging unexpected activation of the collision mitigation braking system (CMBS) in some 2017-2019 Honda CR-V and 2018-2019 Honda Accord vehicles. Driver complaints include high-speed braking incidents occurring with nothing obstructing the vehicle’s path of travel. Of the 278 complaints, 6 allege a collision with minor injuries.
Inadvertent or unexpected braking activation while driving can cause unexpected speed reductions that can lead to increased vulnerability to rear-end impact collisions. The complaints allege that the inadvertent braking events occur without warning and randomly.
Unexpected Brake Activation
2021-2022 Tesla Model 3 and 2021-2022 Tesla Model Y
NHTSA Investigation Number: PE22002
The NHTSA has also received 354 complaints alleging unexpected brake activation in 2021-2022 Tesla Model 3 and 2021-2022 Tesla Model Y vehicles.
Driver reports have been characterized as “phantom braking”. Tesla describes the subject vehicles as equipped with a suite of advanced driver assistance system (ADAS) features referred to as Autopilot which Tesla states will allow the vehicle to brake and steer automatically within its lanes.
The complaints allege that while utilizing the ADAS features including adaptive cruise control, the vehicle unexpectedly applies its brakes while driving at highway speeds. Complainants report that the rapid deceleration can occur without warning, at random, and often repeated in a single drive cycle.
These investigations are a Preliminary Evaluation (PE) to determine the scope and severity of the potential problem and to fully assess the potential of these safety-related issues. If a defect is found, the NHTSA will issue a recall.