Setup the telemetry as you suggested and it works as expected. Thanks for you guidance!
In this step, the Tesla oAuth popup should be shown.
Can you try to hard-close the Homey app (Homey mobile app). This oAuth call is done by Homey/mobile app. Something stopped the GUI to open the html popup.
Thanks for your answer. But I fixed it, opening a private web session and adding the devices. It worked!
Hi Ronny,
I’m trying to add a Tesla Energy Site / Powerwall using Tesla Car & Energy v4.4.8 on a Homey Pro Early 2019.
I created the Tesla Fleet API application according to your instructions, with both allowed origins (athom.com and rwdevelopment.de), the Athom OAuth callback, Authorization Code + Machine-to-Machine, and all requested scopes.
Tesla OAuth completes successfully and redirects to callback.athom.com with “You can now close this window”.
Immediately afterwards Homey returns:
412 Precondition Failed – Account … must be registered in the current region https://fleet-api.prd.na.vn.cloud.tesla.com
Restarting the Homey app and repeating OAuth gives exactly the same result.
My Tesla energy installation/account is in Switzerland.
Could you please advise how the Partner Account should be registered for the NA region, or whether this is something the Homey app should perform automatically during pairing?
Thanks!
Hi, can you please show me a screenshot, where exactly the error is shown? In pair view or in device details? Or just try agian, then send me a diagnostics report. Thanks.
In the past, there have been user accounts in another reqion than the device region. But I’m not sure if that’s the case.
I haven’t got a diagnostics report, but I think it won’t help as the error is shown in the html GUI.
I think it occours by reading devices.
The error looks like your device is registered is another region than your account.
There was an old issue where this happened and the only way to solve it was to change the account region. Can you please look at your account region?
Background: Your account is registered in a region and it also delivers the correct API url. The app is using this URL to access your devices via FleetAPI. So it seems as if either your device or your account is registred in a wrong region. (but that’s only a guess).
@RonnyW is it possible to add the FSD version? I log the software version but that doesn’t include FSD. Thanks!
Hi Ronny, I have the same I think, I fail at the Fleet API partner/domain registration stage.
Homey Pro 2023, Tesla Car & Energy v4.4.8, UK Tesla account, first-ever Tesla Developer application. The application is approved, OAuth succeeds, the app appears under Tesla Third Party Apps, and all 7 scopes are now granted including Profile Information.
Energy Site pairing still fails with:
412 Precondition Failed: Account must be registered in the current region https://fleet-api.prd.na.vn.cloud.tesla.com
Reproducing Car pairing in Homey Developer Tools gives:
422 Validation failed: Domain has already been taken
for both NA and EU domain registration.
Could the Homey-specific domain have been successfully/partially registered during the first attempt, with subsequent attempts then incorrectly trying to register it again? Is there a way to verify or reset the domain registration for this Client ID?
Diagnostics report: ca271ef2-4d70-49ef-93ae-dd3485647ca0
No, there is no way to reset the domain. It’s then bound to your clientID. So just use the client id you used for first login.
Tesla doesn’t offer an API for removing the domain. I requested that but never got an answer…
The domain is a virtual subdomain for your Homey cloud ID and that’s linked to your Tesla client ID.
If you start pairing again with the same client ID, the public certificate is re-used and domain registration is done again. You can force the generation of a new public certificate in client if form (the button below). Perhaps this could fix the domain registration (but I don’t think that’s the reason).
After some research in Tesla documention, the error http 412 error says that the app (client ID) is not yet registered for the Tesla region (NA or EU). In normal pairing, an error in domain registration should stop paiting. Were you able to proceed to oAuth and device list?
I’ll take a look at the Telemetry fields…
I haven’t found a data field for FSD. The only FSD field is: SelfDrivingMilesSinceReset 
Thanks Ronny. I’ve only ever created one Tesla Developer account/application, so there has only ever been one Client ID on this Homey. I am still using that same Client ID.
The domain registration therefore appears to have succeeded/bound during the initial setup, but Energy Site pairing still fails afterwards with:
412 Precondition Failed: Account must be registered in the current region https://fleet-api.prd.na.vn.cloud.tesla.com
My Tesla account region is United Kingdom and OAuth completes successfully. All required scopes are granted.
Fresh diagnostics report:
f1ce10e8-93c7-446e-9350-fbf08ae6cfa4
Hi,
First some words about your log…
I can still see these error from pair/repair:
2026-09-12T13:32:38.654Z [log] [ManagerDrivers] [Driver:car] registerDomain() => Error NA domain registration: 422 Unprocessable Entity: {"response":null,"error":"Validation failed: Domain has already been taken","error_description":"","txid":"7e1af98f6d68e1301485a7dbb91b6981"}
2026-09-12T13:32:39.586Z [log] [ManagerDrivers] [Driver:car] registerDomain() => Error EU domain registration: 422 Unprocessable Entity: {"response":null,"error":"Validation failed: Domain has already been taken","error_description":"","txid":"a20c93d182dbc90b1e61fd0df31e1491"}
You are trying to pair the car, right? There, the domain registration error occours.
That normally means, for Tesla this domain (including your Homey ID) is already registered for a client ID.
The car and the energy site are using independent oAuth authorization, you could also use another Tesla account to add a device. But both must use the same client ID from your developer account, because both are using the domain registration.
The client ID and certificate is Homey specific. The following Tesla oAuth popup is device specific.
Both devices can have different Tesla account/authentification, but both will use the one client ID.
I can see you are using the same client ID for car and energy site (good). But I can also see the domain error.
And I found a pair step issue for Energy Site the caused the app to jump over the domain registration. But like already said, this registration is the same for car and energy site. I fixed it, but I think you will get now also the “domain has taken” error for energy site.
New test version: 4.4.9:
The Homey is your own one or a second hand device? Not that y previous owner already used and registered it for Tesla 
Hi Ronny
Thanks, I did buy this Homey Pro second-hand . So it’s quite possible a previous owner registered the Homey-specific Tesla domain with their own Client ID.
I obviously don’t have access to that Client ID. Given Tesla doesn’t provide an API to remove the domain binding, is there any workaround for a second-hand Homey in this situation?
I opened a ticket at Tesla. But I have no hope that they can/will help.
Do you know the previous user?
