Skip to content

Pedestrian Alert Module

Generates the artificial sound an electric or hybrid vehicle makes at low speed, driving a speaker usually mounted behind the front bumper or inside a wheel arch.

It is the only component in the catalogue whose entire purpose is the safety of somebody outside the vehicle, and that is worth stating because it changes how a fault should be treated. Nothing inside the car depends on it, the driver will never notice it has stopped, and the people it protects have no way to tell that it has.

An electric car at walking pace is close to silent, and that mattered more than anyone anticipated. Pedestrians judge approaching traffic by ear without thinking about it, and blind and partially sighted people rely on it completely. Research following the first wave of hybrids found quiet vehicles measurably more likely to be involved in low-speed pedestrian collisions, which is why the sound is now required rather than optional — UN Regulation 138 in Europe and FMVSS 141 in the United States both mandate it below roughly 20 km/h, above which tyre and wind noise take over.

Its location is the most hostile on the vehicle: road spray, salt, kerb strikes and pressure washers all reach it. Corrosion and water ingress account for most failures, so the repair is often inexpensive — and in jurisdictions that test for it, an inoperative system is an inspection failure.

Also known as: pedestrian alert, acoustic vehicle alerting system, avas, vehicle sound generator, pedestrian warning system, approach warning speaker, low speed sound generator

Referenced by 3 codes

WhatsApp Telegram X Email

Codes involving this component (3)

Other components in Body, Interior and Safety

Information, not instruction

CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.

Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.

Working on this component

Be the first to write this up

Nothing posted about this yet. Whatever you found is worth writing down — even a dead end saves someone the same afternoon.

What makes one worth reading:

  • The car — make, model, year and engine. The same fault behaves differently on each.
  • What you measured, not only what you replaced.
  • What actually fixed it — or that nothing did, which is worth knowing too.

Sign in or create an account to add what you found about Pedestrian Alert Module.