VESS (noise) defeat

Overview

There is a lout beep/bong whne in reverse. On the 2020, the level of the beeping when backing up is really loud, like 85 dB.

It is in a speaker behind the front nose trim, where you cannot see it.

The goal is to stifle the backup warning noise, either mute it, or have a variable volume.

First investigation

When my car was new, most of the documentation was on the 2019. In this model, the speaker in the grill is just a speaker, and there was the CAN bus component and audio amplifier behind/above the glove box.

So I pull the dash apart and take out the glove box, and the unit is not there.

I found someone that had investigate how this works, and funny enough he is a large scale train guy also: Eric Reuter, he has a Hyundai Kona. While the CAN bus unit/speaker may be the same, the wiring is different in the Kia.

He did have some fun though, he sniffed the CAN bus and found the commands being sent.

well, fun but no help to disable.

Further

I investigated the wiring by inspection, I did not have the schematic, but ENiorgus on the insideevsforum.com did get it.

Different countries have different switch panels, and of course mine has a blank switch. I tried to follow the contacts back from the blank switch, but they went to an empty position on the connector to the switch panel.

I got the schematic on the Kona, so pretty sure the wires were there somewhere:

But the wiring in the Niro was different, the pins on my switch panel did not line up with the pins on this schematic, i.e. pin 7.

Finally someone got the Niro schematic, and traced the VESS defeat wire down to the connector:

see this post on the insideevsforum:

https://www.insideevsforum.com/community/index.php?threads/2020-kia-e-niro-vess-reverse-chime-defeat-solution.11245/

so with the right schematic, you find the wire to be grounded is blue with a black stripe, on pin 9. There is a nice ground on pin 24.

Clearly you can add an LED to show status, to the pink wire on pin 10, lit when defeated.

The author also noted that the wire size is 0.3 sq mm so that is closest to 22 gauge, so if you use clamp on wire taps, the red ones are right

Here is the numbered pins on the connector:

Alternatives:

You can also apparently unplug the unit reaching down near the radiator (other methods say to remove the entire front clip

https://youtu.be/kOCnVrW3BQA