ACC surging behaviour

Talismutt | 2026-02-08 23:01 | 22 views

Had my Atto 3 for around 6 months now and absolutely love the car. Took it for it's first long distance drive where it performed perfectly, charged quick enough at each stop every 2 hrs, all went well. It did exhibit one unusual behaviour when using ACC at 110 on the Hume freeway. Whenever there was a dip in the road (e.g. over a bridge expansion joint) when the car would bounce up and down the ACC would surge up and down. From a steady 10 or so kW up to 30 or so kW and back down. Has anyone else seen this behaviour? I'm expecting it's a trip to a service center for some calibration, haven't seen any settings I can change. Or could it be dirt/dead bugs on the sensors?

Comments (13)

r1chardj0n3s 2026-02-08 23:03

Yeah my Dolphin does that at all speeds if there's small undulations in the road. The ACC is too touchy in general.

thechakaexpress 2026-02-08 23:04

I have the same car, the cruise control is horrible and experience the exact same thing. It is worse in ECO mode but still happens in Normal mode.

Suntzu_AU 2026-02-08 23:09

The cruise control in my three year Atto 3 is frankly completely untrustworthy. It will break hard when it sees an overhead bridge for example.

Psychlonuclear 2026-02-08 23:11

Pure speculation here but I think the sensor might be pointing a bit too far down on BYD cars so it registers the road ahead as a car/obstacle when the car tilts down slightly when going over a bump.

Sweet_Word_3808 2026-02-09 00:13

I haven't seen this particular issue in my Atto 3, but I've only ever done the Hume as far as Canberra in the Atto and I rarely use ACC outside of multilane highways. I'll add that I did a USB update to version 1.10 which AFAIK isn't available yet in Australia as an OTA quite a few months back and it included some ACC and lane keep refinement. It feels a lot more sure footed now and I have less issues now with jerkiness on gentle curves (like around Lake George) where it used to do lots of little micro corrections to follow the curve instead of a continuous steer.

Talismutt 2026-02-09 00:26

Interesting, had it in ECO mode, didn't think to try changing modes. I normally drive around town in Sport mode which might explain why I haven't felt it before. Have a diesel I usually use for longer road trips, but this one was only Melbourne to Albury so thought I'd give the Atto a go.

orewaAfif 2026-02-09 01:13

Yeah I think this is the case. Whenever there's a dip where the sensor might see the road, it will try to brake hard.

ShadowxWarrior 2026-02-09 01:57

No, it accelerates in the dip. I have it too.

Talismutt 2026-02-09 01:59

Yes it accelerates in the dip

JizahB 2026-02-09 03:05

Yeah I will drive in the middle of the road when approaching parked cars going down my street but it will still randomly decide to heavily phantom brake, and my street is incredibly wide.

SexyDraenei 2026-02-09 03:33

my seal did this when i first got it. either they fixed it in an update or I got used to it, but I didn't notice it after the first month or so.

WinterBarnacles 2026-02-09 06:53

My Seal also does this. I haven't really felt it at high speeds (the expressways here are pretty smooth) but it's pretty uncomfortable on bumpy roads. It's bad enough that I just don't use the ACC on bumpy roads unless I'm really tired.

WinterBarnacles 2026-02-09 10:13

Wow, I just tried it in Sport and it seemed way better. It hadn't occurred to me to try that, I thought it would just accelerate into dips faster.

Add comment