Incorrect degradation rate after update 2025.38.3.1

[viorelovidiu]

Is there an existing issue for this?

• I have checked the existing issues and discussions, and I can confirm that there are no duplicates.

What happened?

Hello,
After updating to version 2025.38.3.1, degradation went down to 0% from 2,4% and now reporting a higher capacity at 100% - 76kWh increased to 82kWh according to Battery health dashboard.
My car is a Model Y Juniper 2025 with 20" wheels. Just before the update, I have changed the wheels with winter set on 19" and also updated the configuration on the car settings. Range reported at 100% increased also from 475km to 515km.
If not related to the updated, it could be a bug related to changing the wheel size with battery health dashboard.

Expected Behavior

real degradation rate

Can the issue reliably be reproduced?

Yes

Steps To Reproduce the issue

update to firmware 2025.38.x
or
change the wheel size only from service menu of the car.

Relevant log output

attached log

Screenshots

docker-teslamate-1.html

Additional data

No response

Type of installation

Docker (https://docs.teslamate.org/docs/installation/docker/)

Version

v2.1.1

PostgreSQL version

v17.4

Are you running latest major supported PostgreSQL version?

• I run the latest major supported PostgreSQL version

Are you using a reverse Proxy for TeslaMate?

No

Details about your reverse Proxy if applicable

No response

[swiffer]

Most likely a duplicate of #4729

Teslamate is using an average for efficiency (over all charges) and not logging changes of wheel size but tesla is changing the efficiency based on selected wheel size.

We would need to log wheel_type per charge/drive and base our efficiency readings on that.

[viorelovidiu]

Most likely a duplicate of #4729

Teslamate is using an average for efficiency (over all charges) and not logging changes of wheel size but tesla is changing the efficiency based on selected wheel size.

We would need to log wheel_type per charge/drive and base our efficiency readings on that.

Hi, I was suspected that might be related to wheel changes. However, Scan my tesla and sexy buttons cannot see the value of nominal pack when new and because of that, degradation rate is also 0%. But teslamate does not look at that values.
What is curious, on my previous Model Y perfomance when I have switched from 21" to 19", nothing has changed in range estimation at 100% both in car and teslamate. Maybe because it was related to homologation number that was allowing only 21" no matter what wheels size I have choosen in the menu being an earlier production.

[swiffer]

Maybe - to verify it's caused by the change in wheel_type and not related to the update you could change the wheel_type, charge and validate via grafana.