> ## Documentation Index > Fetch the complete documentation index at: https://smartcar.com/docs/llms.txt > Use this file to discover all available pages before exploring further. # Set nominal battery capacity > Set the vehicle's nominal battery capacity, overriding the value Smartcar derives for it. Must be one of the `availableCapacities` reported by the `tractionbattery-nominalcapacity` signal. Simulated vehicles accept any capacity from 10 to 200 kWh. ## OpenAPI ````yaml /specs/full-vehicle.yaml post /vehicles/{vehicleId}/settings/tractionbattery-nominalcapacity openapi: 3.0.3 info: title: Smartcar Vehicle API (Complete) version: 3.0.0 description: API for vehicle data (signals) and operations (commands). servers: - url: https://vehicle.api.smartcar.com/v3 security: [] tags: - name: Charging description: Commands for controlling vehicle charging behavior. - name: Security description: Commands for controlling vehicle door locks. - name: Navigation description: Commands for setting destinations in the vehicle navigation system. - name: Charge Schedules description: Create, retrieve, and delete recurring charge schedules on a vehicle. - name: Charge description: Signals and attributes for the Charge group. - name: Climate description: Signals and attributes for the Climate group. - name: Closure description: Signals and attributes for the Closure group. - name: ConnectivitySoftware description: Signals and attributes for the ConnectivitySoftware group. - name: ConnectivityStatus description: Signals and attributes for the ConnectivityStatus group. - name: Diagnostics description: Signals and attributes for the Diagnostics group. - name: HVAC description: Signals and attributes for the HVAC group. - name: InternalCombustionEngine description: Signals and attributes for the InternalCombustionEngine group. - name: Location description: Signals and attributes for the Location group. - name: LowVoltageBattery description: Signals and attributes for the LowVoltageBattery group. - name: Motion description: Signals and attributes for the Motion group. - name: Odometer description: Signals and attributes for the Odometer group. - name: Service description: Signals and attributes for the Service group. - name: Surveillance description: Signals and attributes for the Surveillance group. - name: TractionBattery description: Signals and attributes for the TractionBattery group. - name: Transmission description: Signals and attributes for the Transmission group. - name: VehicleIdentification description: Signals and attributes for the VehicleIdentification group. - name: VehicleUserAccount description: Signals and attributes for the VehicleUserAccount group. - name: Wheel description: Signals and attributes for the Wheel group. paths: /vehicles/{vehicleId}/settings/tractionbattery-nominalcapacity: post: summary: Set nominal battery capacity description: > Set the vehicle's nominal battery capacity, overriding the value Smartcar derives for it. Must be one of the `availableCapacities` reported by the `tractionbattery-nominalcapacity` signal. Simulated vehicles accept any capacity from 10 to 200 kWh. operationId: setTractionBatteryNominalCapacity parameters: - in: path name: vehicleId description: The unique identifier for the vehicle. schema: type: string example: v_123abc456def required: true - in: header name: sc-user-id required: true description: > The identifier of the vehicle user on whose behalf the request is being made. These requests require both the `vehicleId` (path) and `sc-user-id` (header) to identify the specific vehicle and the user who has granted permission to act on it. The bearer token is a machine-to-machine token and does not carry per-user context, so this header must be provided explicitly for every request being made. schema: type: string example: user_789xyz requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/NominalCapacitySettingRequest' responses: '201': description: The nominal battery capacity was set content: application/json: schema: $ref: '#/components/schemas/NominalCapacitySettingDataResource' '400': $ref: '#/components/responses/BadRequest1' '401': $ref: '#/components/responses/Unauthorized' '403': $ref: '#/components/responses/Forbidden' '404': $ref: '#/components/responses/NotFound1' '500': $ref: '#/components/responses/InternalError' security: - bearerAuth: [] components: schemas: NominalCapacitySettingRequest: type: object required: - data properties: data: type: object required: - attributes properties: attributes: type: object required: - capacity properties: capacity: type: number description: > The nominal battery capacity in kWh. Must be one of the vehicle's available capacities. example: data: attributes: capacity: 75 NominalCapacitySettingDataResource: type: object required: - data properties: data: $ref: '#/components/schemas/NominalCapacitySettingResource' example: data: id: tractionbattery-nominalcapacity type: vehicle-setting attributes: value: capacity: 75 unit: kWh source: APPLICATION meta: updatedAt: '2026-10-15T20:00:00Z' links: affectedSignals: - >- https://vehicle.api.smartcar.com/v3/vehicles/vehicle123/signals/tractionbattery-nominalcapacity NominalCapacitySettingResource: type: object required: - id - type - attributes - meta - links properties: id: type: string enum: - tractionbattery-nominalcapacity type: type: string enum: - vehicle-setting attributes: type: object required: - value - source properties: value: $ref: '#/components/schemas/NominalCapacitySettingValue' source: type: string description: Who set the value. enum: - APPLICATION meta: type: object required: - updatedAt properties: updatedAt: type: string format: date-time description: | ISO 8601 UTC date string of when the setting was updated links: type: object required: - affectedSignals properties: affectedSignals: type: array description: The signals whose values change with this setting. items: type: string ErrorResponse: type: object required: - errors properties: errors: type: array minItems: 1 items: type: object required: - status - type - code - title - detail properties: status: type: string type: type: string enum: - AUTHENTICATION - BILLING - COMPATIBILITY - CONNECTED_SERVICES_ACCOUNT - RATE_LIMIT - RESOURCE_NOT_FOUND - SERVER - UPSTREAM - VALIDATION - VEHICLE_STATE code: type: string title: type: string detail: type: string resolution: type: object description: >- Optional field providing guidance on how to resolve the error, if applicable. The structure of this object can vary based on the error type and is intended to provide actionable information to clients. properties: type: type: string description: >- The type of resolution recommended (e.g., "RETRY_LATER", "CONTACT_SUPPORT", etc.) suggestedUserMessage: type: string description: >- Optional field providing a user-friendly message that can be displayed to end-users, if applicable. This message is intended to be easily understandable and actionable for users who encounter the error. links: type: object properties: about: type: string format: uri meta: type: object properties: debug: type: object description: >- Debug information for internal use, not intended for clients properties: applicationId: type: string description: The unique identifier for the application requestId: type: string description: The unique identifier for the request origin: type: string description: The origin of the error example: applicationId: app_123abc requestId: req_456def origin: internal.com/path NominalCapacitySettingValue: type: object required: - capacity - unit properties: capacity: type: number description: The nominal battery capacity. unit: type: string enum: - kWh responses: BadRequest1: description: 400 Bad Request content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: errors: - status: '400' type: VALIDATION code: BAD_REQUEST title: Bad Request detail: >- The request could not be understood by the server due to malformed syntax. links: about: >- https://smartcar.com/docs/errors/api-errors/v3/validation-errors Unauthorized: description: 401 Unauthorized content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: errors: - status: '401' type: AUTHENTICATION code: UNAUTHORIZED title: Unauthorized detail: The Authorization token is missing or invalid. links: about: >- https://smartcar.com/docs/errors/api-errors/v3/authentication-errors#authentication Forbidden: description: 403 Forbidden content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: errors: - status: '403' type: AUTHENTICATION code: FORBIDDEN title: Forbidden detail: You do not have permission to access this resource. links: about: >- https://smartcar.com/docs/errors/api-errors/v3/authentication-errors NotFound1: description: 404 Not Found content: application/json: schema: type: object required: - errors properties: errors: type: array minItems: 1 items: type: object required: - status - type - code - title - detail properties: status: type: string type: type: string enum: - AUTHENTICATION - BILLING - COMPATIBILITY - CONNECTED_SERVICES_ACCOUNT - RATE_LIMIT - RESOURCE_NOT_FOUND - SERVER - UPSTREAM - VALIDATION - VEHICLE_STATE code: type: string title: type: string detail: type: string resolution: type: object description: >- Optional field providing guidance on how to resolve the error, if applicable. The structure of this object can vary based on the error type and is intended to provide actionable information to clients. properties: type: type: string description: >- The type of resolution recommended (e.g., "RETRY_LATER", "CONTACT_SUPPORT", etc.) suggestedUserMessage: type: string description: >- Optional field providing a user-friendly message that can be displayed to end-users, if applicable. This message is intended to be easily understandable and actionable for users who encounter the error. links: type: object properties: about: type: string format: uri meta: type: object properties: debug: type: object description: >- Debug information for internal use, not intended for clients properties: applicationId: type: string description: The unique identifier for the application requestId: type: string description: The unique identifier for the request origin: type: string description: The origin of the error example: applicationId: app_123abc requestId: req_456def origin: internal.com/path example: errors: - status: '404' type: RESOURCE_NOT_FOUND code: NOT_FOUND title: Not Found detail: The requested resource could not be found. links: about: >- https://smartcar.com/docs/errors/api-errors/v3/resource-not-found-errors InternalError: description: 500 Internal Server Error content: application/json: schema: $ref: '#/components/schemas/ErrorResponse' example: errors: - status: '500' type: SERVER code: INTERNAL title: Internal Server Error detail: An unexpected error occurred on the server. links: about: https://smartcar.com/docs/errors/api-errors/v3/server-errors securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: JWT or opaque description: | The Authorization header must be provided with a valid bearer token. Example: `Authorization: Bearer {token}` ````