> ## 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.

# Connection Filters

> Restrict which vehicles can connect to your application based on powertrain type.

Connection Filters let you restrict connections to specific powertrain types. By default, all powertrain types are allowed. Vehicles that don't match your selection will be blocked from completing the Connect flow.

Configure this in the **Connection Filters** tab in your application's Configuration page on the [Smartcar Dashboard](https://dashboard.smartcar.com).

<Info>Connection Filters are available on the Custom plan.</Info>

## Powertrain Filter

You can allow or block connections based on the following powertrain types:

| Type   | Description                                                                                              |
| ------ | -------------------------------------------------------------------------------------------------------- |
| `ICE`  | Internal Combustion Engine — includes traditional combustion engines and hybrid electric vehicles (HEVs) |
| `BEV`  | Battery Electric Vehicle                                                                                 |
| `PHEV` | Plug-in Hybrid Electric Vehicle                                                                          |

All three types are allowed by default. Uncheck any type to block vehicles of that type from connecting to your application.

<Info>
  If no powertrain types are selected, the filter is not applied and all types are allowed to connect.
</Info>

Changes take effect after you click **Publish** in the dashboard.

## Block Unknown Powertrains

When you restrict connections to a subset of powertrain types, an additional checkbox appears: **Allow connections when powertrain is 'UNKNOWN'**.

When this checkbox is checked, vehicles whose powertrain type cannot be determined at connection time are allowed to connect. When unchecked, those vehicles are blocked.

<Info>
  When a vehicle's powertrain cannot be verified at connection time, it is classified as 'UNKNOWN'. This affects roughly 1% of connections due to manufacturer data limitations.
</Info>