MG4 EH32 S: totalBatteryCapacity at 64 instead of 77kWh due to changes in SAIC API values

[manliojrc]

Since yesterday, I noticed weird values being reported.

Digging in, I realised that the totalBatteryCapacity is erroneously set at 64 instead of 77 kWh.

saic/XXX/vehicles/XXX/info/model MG4 ELECTRIC
saic/XXX/vehicles/XXX/info/year 2022
saic/XXX/vehicles/XX/info/series EH32 S
saic/XXX/vehicles/XXX/info/model EH32 X3
saic/XXX/vehicles/XXX/drivetrain/totalBatteryCapacity 64.0

saic/XXX/vehicles/XXX/drivetrain/soc_kwh 51.2
saic/XXX/vehicles/XXX/drivetrain/soc 80.0

which means that I was expecting the soc_kwh value to be 61.6, and instead it is set to 51.2 kWh.

[manliojrc]

The more I look into it, the more confusing it gets. Let's start from the fact that the car is now sitting at 80% battery after being recharged. Thus, being an XR model, the SoC value is 61.6 kWh.

The percentage reported by the gateway is 66.49%, which, coupled with 64 kWh of reported total capacity and 51.2 kWh reported as stored, does not make much sense; it should be 80% for calculations to be coherent. So the 66.49% is actually correct (reported battery level is 51.2 kWh out of 77 kWh total capacity, which is 66.49%), but the SoC value is not.

So I think the error is on totalBatteryCapacity and values that are derived from it, and not read from telemetry. Is it correct? Are there values being calculated using the totalBatteryCapacity as a parameter?

[nanomad]

@manliojrc The way it work is that we try to figure out the real capacity via a lookup table using series/model as the key sice the API reports all values based of 77kWh. I'll plug your values into the lookup logic to see what happens.

[nanomad]

Uhm why do you have two values for
saic/XXX/vehicles/XXX/info/model MG4 ELECTRIC
saic/XXX/vehicles/XXX/info/model EH32 X3

?

Did they update the API to just report "MG4 ELECTRIC" for yours as well? What does HA show for your car?

[nanomad]

To triage this please:

• Upgrade to 0.10.0-rc3 or later
• set PUBLISH_RAW_API_DATA_ENABLED=True
• dump content of topic: saic/_internal/api/vehicle/list/response
• Post the content removing VIN and headers section

[manliojrc]

I don't use HA.

saic/_internal/api/vehicle/list/response {
  "path": "/vehicle/list",
  "query": {},
  "body": {
    "code": 0,
    "data": {                                                                                                                     "vinList": [
        {
          "colorName": "BLACK PEARL",
          "isSubaccount": true,
          "brandName": "MG",
          "vehicleModelConfiguration": [
            {
              "itemName": "Tire",
              "itemCode": "J17",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "Airbag",
              "itemCode": "Q00",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "FAirbag",
              "itemCode": "Q01",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "AirbagS",
              "itemCode": "Q09",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "Sunroof",
              "itemCode": "S35",
              "itemValue": "0",
              "itemValueValid": "0"
            },
            {
              "itemName": "Remote control",
              "itemCode": "S61",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "AC",
              "itemCode": "T11",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "EPS",
              "itemCode": "EPS",
              "itemValue": "1",
              "itemValueValid": "1"
            },
			            {
              "itemName": "SA64",
              "itemCode": "SA64",
              "itemValue": "0111110000000000001000000100101000000010100000000000000000000110",
              "itemValueValid": "0111110000000000001000000100101000000010100000000000000000000110"
            },
            {
              "itemName": "BONNUT",
              "itemCode": "BONNUT",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "DOOR",
              "itemCode": "DOOR",
              "itemValue": "1111",
              "itemValueValid": "1111"
            },
            {
              "itemName": "BOOT",
              "itemCode": "BOOT",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "ENGINE",
              "itemCode": "ENGINE",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "EV",
              "itemCode": "EV",
              "itemValue": "0",
              "itemValueValid": "0"
            },
            {
              "itemName": "HeatedSeat",
              "itemCode": "HeatedSeat",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "KEYPOS",
              "itemCode": "KEYPOS",
              "itemValue": "0",
              "itemValueValid": "0"
            },
            {
              "itemName": "ENERGY",
              "itemCode": "ENERGY",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "BATTERY",
              "itemCode": "BATTERY",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "INTEMP",
              "itemCode": "INTEMP",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "EXTEMP",
              "itemCode": "EXTEMP",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "WINDOW",
              "itemCode": "WINDOW",
              "itemValue": "0000",
              "itemValueValid": "0000"
            },
            {
              "itemName": "LRD",
              "itemCode": "LRD",
              "itemValue": "0",
              "itemValueValid": "0"
            },
            {
              "itemName": "BTKEY",
              "itemCode": "BTKEY",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "Battery",
              "itemCode": "BType",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "SBH",
              "itemCode": "SBH",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "BHI",
              "itemCode": "BHI",
              "itemValue": "1",
              "itemValueValid": "1"
            },
            {
              "itemName": "ROV",
              "itemCode": "ROV",
              "itemValue": "25857",
              "itemValueValid": "25857"
            }
          ],
          "countryRegionCode": "3G02",
          "modelYear": "2022",
          "modelName": "MG4 Electric",
          "bindTime": 1735803835000,
          "series": "EH32 S",
          "isCurrentVehicle": true,
          "vin": "XXX",
          "subaccountInfo": {
            "subaccountId": XXX,
            "locationAuthorization": 1,
            "subscriberId": XXX,
            "userName": "XXX",
            "authorizedSubscriberId": XXX,
            "isCurrentVehicle": 0,
            "validityEndTime": 0,
            "userAccount": "XXX",
            "validityStartTime": 1735807408,
            "vin": "XXX",
            "operationType": 2,
            "authorizationCardType": 1,
            "status": 1,
            "createDate": "2025-01-02 08:43:55"
          },
          "isActivate": false
        }
      ]
    },
    "message": "success"
  },
}

[nanomad]

They finally fixed the bug we were relying on to identify if it was a 77kWh model or not...

But worry not, you can customize your battery capacity in two ways:

BATTERY_CAPACITY_MAPPING environment variable. Syntax of the value is VIN=new capacity.

e.g.
BATTERY_CAPACITY_MAPPING=LSJSOMETHING=77.0
If you have multiple cars you can separate them via comma

Starting from 0.10.0-rc4, you can publish a retained message to

saic/{{ACCOUNT}}/vehicles/{{VIN}}/refresh/drivetrain/totalBatteryCapacity/set

To customize the battery capacity. It will be used at start up time as well as every gateway refresh