> ## Documentation Index
> Fetch the complete documentation index at: https://docs.connectedfleet.michelin.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Tire Defects

Tire defects represent issues detected during tire inspections that require attention, ranging from low pressure warnings to critical wear conditions. The defect system categorizes, prioritizes, and tracks issues throughout their lifecycle to help fleet managers maintain safe and efficient operations.

## Overview

The Smart Tire API provides access to tire defect history through the [Tire Defect Events](/api-reference/tire/tire-defect-events) endpoint. Per request, You can retrieve defects for specific vehicles, groups, or your entire fleet within a date range of up to 6 months.

## Defect Structure

Each defect includes comprehensive information to help you understand and address the issue:

| Field          | Description                                                       |
| -------------- | ----------------------------------------------------------------- |
| `category`     | High-level classification of the defect                           |
| `type`         | Specific type of defect                                           |
| `entityType`   | Whether the defect affects a tire, axle, or vehicle               |
| `severity`     | Priority level for addressing the defect                          |
| `inProgress`   | Whether the defect is still active (`true`) or resolved (`false`) |
| `creationDate` | When the defect was first detected                                |
| `updateDate`   | When the defect was last updated                                  |
| `properties`   | Additional details specific to the defect type                    |

## Defect Categories

Defects are classified into the following high-level categories:

| Category                 | Description                                                |
| ------------------------ | ---------------------------------------------------------- |
| `WEAR`                   | Tread depth has reached concerning levels                  |
| `PRESSURE`               | Tire pressure is outside acceptable range                  |
| `TEMPERATURE`            | Tire temperature is abnormally high                        |
| `CONFIG_WEAR`            | Configuration mismatch detected during wear inspection     |
| `CONFIG_PRESSURE`        | Configuration mismatch detected during pressure inspection |
| `NOT_INSTALLED_PRESSURE` | Expected TPMS sensor not reporting pressure data           |
| `NOT_INSTALLED_WEAR`     | Tire position not detected during wear scan                |
| `MANUAL`                 | Defect manually reported by an operator                    |

## Defect Types

More specific defect classifications within each category:

| Type                 | Description                                             |
| -------------------- | ------------------------------------------------------- |
| `WEAR`               | General tread wear defect                               |
| `CONICITY`           | Uneven wear causing the tire to pull to one side        |
| `TTC`                | Time to Critical — tire approaching critical wear level |
| `WEAR_TTC`           | Combined wear and time-to-critical alert                |
| `PRESSURE`           | Pressure outside normal range                           |
| `PRESSURE_TTC`       | Pressure defect approaching critical threshold          |
| `INCONSISTENCY`      | Mismatched tires on the same axle                       |
| `MANUAL`             | Manually reported defect                                |
| `PRESSURE_FOOTPRINT` | Pressure anomaly detected via footprint analysis        |

## Entity Types

Defects can affect different levels of the vehicle:

| Entity Type | Description                    | Example                           |
| ----------- | ------------------------------ | --------------------------------- |
| `TIRE`      | Affects a single tire          | Low pressure on front left tire   |
| `AXLE`      | Affects an entire axle         | Mismatched tires on rear axle     |
| `VEHICLE`   | Affects the vehicle as a whole | Vehicle-level inspection required |

<Note>
  Axle-level defects typically indicate configuration issues such as mismatched tire brands, sizes, or significantly different wear levels between tires on the same axle.
</Note>

## Severity Levels

Defects are assigned severity levels to help prioritize maintenance:

| Severity        | Description               | Recommended Action                 |
| --------------- | ------------------------- | ---------------------------------- |
| `INFORMATION`   | Advisory notice           | Monitor during next inspection     |
| `ATTENTION`     | Requires monitoring       | Schedule inspection soon           |
| `MINOR`         | Low priority issue        | Address during routine maintenance |
| `MODERATE`      | Medium priority issue     | Schedule maintenance within days   |
| `MAJOR`         | High priority issue       | Address promptly                   |
| `CRITICAL`      | Safety-critical issue     | Immediate action required          |
| `NOT_INSTALLED` | Equipment not detected    | Verify sensor/tire installation    |
| `OTHER_ACTION`  | Non-standard intervention | Review and determine action        |

<Warning>
  **Critical defects require immediate attention.** Vehicles with critical tire defects should be taken out of service until the issue is resolved to prevent safety incidents.
</Warning>

## Defect Properties

The `properties` object contains additional details specific to each defect type:

### Common Properties

| Property    | Description                                         |
| ----------- | --------------------------------------------------- |
| `dueDate`   | Predicted date when the defect will become critical |
| `positions` | Array of tire positions affected by the defect      |

### Pressure-related Properties

| Property             | Unit         | Description                           |
| -------------------- | ------------ | ------------------------------------- |
| `pressure`           | Pascals (Pa) | Measured tire pressure                |
| `normalizedPressure` | Pascals (Pa) | Pressure adjusted to 20°C reference   |
| `temperature`        | Celsius (°C) | Tire temperature at time of detection |

### Wear-related Properties

| Property                 | Unit | Description                                            |
| ------------------------ | ---- | ------------------------------------------------------ |
| `conicity`               | mm   | Measurement of uneven wear                             |
| `grooveHeightDifference` | mm   | Difference in groove depth (for inconsistency defects) |

## Filtering Defects

### By Severity

Filter to retrieve only defects of specific severity levels:

```bash theme={null}
curl --request GET \
  --url 'https://public-api.masternautconnect.com/public/v1/customer/{customerId}/asset/tire/defect/history?startDate=2025-01-01T00:00:00Z&endDate=2025-01-31T23:59:59Z&severities=CRITICAL,MAJOR' \
  --header 'Authorization: Token <your-api-token>'
```

### By Vehicle

Retrieve defects for a specific vehicle:

```bash theme={null}
curl --request GET \
  --url 'https://public-api.masternautconnect.com/public/v1/customer/{customerId}/asset/tire/defect/history?startDate=2025-01-01T00:00:00Z&endDate=2025-01-31T23:59:59Z&assetId={assetId}' \
  --header 'Authorization: Token <your-api-token>'
```

### By Group

Retrieve defects for all vehicles in a group:

```bash theme={null}
curl --request GET \
  --url 'https://public-api.masternautconnect.com/public/v1/customer/{customerId}/asset/tire/defect/history?startDate=2025-01-01T00:00:00Z&endDate=2025-01-31T23:59:59Z&groupId={groupId}' \
  --header 'Authorization: Token <your-api-token>'
```

## Use Cases

### Daily Safety Check

Retrieve all critical and major defects from the past 24 hours:

```bash theme={null}
curl --request GET \
  --url 'https://public-api.masternautconnect.com/public/v1/customer/{customerId}/asset/tire/defect/history?startDate=2025-01-20T00:00:00Z&endDate=2025-01-21T00:00:00Z&severities=CRITICAL,MAJOR' \
  --header 'Authorization: Token <your-api-token>'
```

### Maintenance Planning

Retrieve all defects to build a maintenance schedule based on severity and due dates:

```bash theme={null}
curl --request GET \
  --url 'https://public-api.masternautconnect.com/public/v1/customer/{customerId}/asset/tire/defect/history?startDate=2025-01-01T00:00:00Z&endDate=2025-06-30T23:59:59Z' \
  --header 'Authorization: Token <your-api-token>'
```

### Alert Integration

Poll for new defects regularly and integrate with your alerting or ticketing system:

1. Query defects with a recent `startDate`
2. Filter for `inProgress: true` to get active defects
3. Create tickets or alerts based on severity
4. Track `updateDate` to detect status changes

<Info>
  The date range for defect queries cannot exceed 6 months. For longer historical analysis, make multiple requests with consecutive date ranges.
</Info>