Electric vehicle warning sounds

Electric vehicle warning sounds are a series of sounds designed to alert pedestrians to the presence of electric drive vehicles such as hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), and all-electric vehicles (EVs) travelling at low speeds. Warning sound devices were deemed necessary because vehicles operating in all-electric mode produce less noise than traditional combustion engine vehicles and can make it more difficult for pedestrians, the blind, cyclists, and others, to be aware of their presence. Warning sounds may be driver triggered (as in a horn but less urgent) or automatic at low speeds; in type, they vary from clearly artificial (beeps, chimes) to those that mimic engine sounds and those of tires moving over gravel.

Japan issued guidelines for such warning devices in January 2010 and the U.S. approved legislation on December 2010. The U.S. National Highway Traffic Safety Administration ruled in November 2016 that warning sounds are mandatory from September 2019 for electrified vehicles travelling at less than 19 mph (30 km/h) or going in reverse. The European Parliament approved legislation that requires the mandatory use of "Acoustic Vehicle Alerting Systems" for all new electric and hybrid electric vehicles within 5 years after publication of the final approval of the April 2014 proposal to comply with the regulation.

Several automakers have developed electric warning sound devices, and since December 2011 advanced technology cars available in the market with manually activated electric warning sounds include the Nissan Leaf, Chevrolet Volt, Honda FCX Clarity, Nissan Fuga Hybrid/Infiniti M35, Hyundai Sonata Hybrid, and the Toyota Prius (Japan only). Models equipped with automatically activated systems include the 2014 BMW i3 (option not available in the US), 2012 model year Toyota Camry Hybrid, 2012 Lexus CT200h, all EV versions of the Honda Fit, and all Prius family cars recently introduced in the United States, including the standard 2012 model year Prius, the Toyota Prius v, Prius c and the Toyota Prius Plug-in Hybrid. The 2013 Smart electric drive comes with automatically activated sounds in the U.S. and Japan and manually activated in Europe.Tesla Motors and Volkswagen do not currently include warning sounds in their electric drive vehicles, as all of them decided to add artificial sounds only when required by regulation.

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Wikipedia