OWNER ANSWER
BYD reversing noise: pedestrian warning sound or a fault?
A steady exterior sound while reversing can be BYD’s pedestrian warning system, AVAS. A parking-sensor beep or a new grinding, scraping or clunking noise is different, so describe the sound and when it occurs before deciding what needs checking.
- Compare what you already heard: steady outside tone, obstacle beep or harsh mechanical noise. Safety note: AVAS alerts nearby pedestrians. Keep it operating, keep people out of the car’s path and avoid extra reversing just to collect a recording; stop safely if braking, steering or control changes.
- Check the AVAS section for your exact model and edition in the sources below.
- If the expected pedestrian sound is absent or a noise has changed, ask BYD to assess that specific symptom.
What the seven handbooks agree on
The cited ATTO 2, original ATTO 3, EVO, DOLPHIN, SURF, original SEAL and SEALION 7 sections describe a continuous reversing warning sound. Their optional controls, speed thresholds and missing-sound checks differ, so use the matching edition.
What to describe
Tell the repairer whether it was only in Reverse, also in Drive, or linked to braking or steering. Recent tyre or servicing work and existing warning messages are useful context.
If that did not work
Ask BYD to check AVAS if its expected sound is absent. For a new mechanical noise, request inspection of the affected brake, wheel or drive-system symptom; changed vehicle control needs assistance.
Related links
Source: ATTO 2 handbook (PDF 130–131; printed 129–130) · ATTO 3 handbook (PDF 133–134; printed 132–133) · ATTO 3 EVO handbook (PDF 172; printed 171) · DOLPHIN handbook (PDF 134; printed 133) · DOLPHIN SURF handbook (PDF 116–117; printed 115–116) · SEAL handbook (PDF 137–138; printed 136–137) · SEALION 7 handbook (PDF 164–165; printed 163–164). Checked 22 October 2026.