Vehicle Health & Diagnostic Trouble Codes (DTC) Guide

Vehicle Health & Diagnostic Trouble Codes (DTC) Guide

Fleetr captures real-time engine diagnostics to monitor overall vehicle health, identify faults early, and prevent costly breakdowns.

1. How Fleetr Collects DTC Data

Diagnostic Trouble Codes (DTC) are retrieved directly from your vehicle’s onboard computer via the connected OBD device. Fleetr reads these raw manufacturer error codes and translates them into clear, actionable fault descriptions, probable causes, and suggested fixes.

2. Where to View Vehicle Health & DTCs

You can check your fleet's diagnostic status from two main areas in the platform:

  • Vehicles Module: Select Vehicles from the left-hand menu and choose a specific vehicle. Look for the heart icon next to the vehicle name—its color indicates the vehicle's current health status.

  • Health / Engine Error Codes Module: Access the dedicated health module to view engine error codes across your entire fleet or filter vehicles by their specific health state.

3. Understanding Health Status Colors

Vehicle health conditions are categorized into three color-coded tiers:

ColorStatusDescription
GreenGood ConditionVehicle system is operating normally with 0 active error codes.
YellowBad ConditionActive minor or non-critical error codes detected. Inspection recommended.
RedCritical ConditionSerious engine/system fault detected requiring immediate maintenance.

4. Diagnostic Mapping & Code Details

Selecting any vehicle displaying an active fault opens a detailed diagnostic panel:

  • System Component Mapping: Visual breakdown highlighting where the error originates in the vehicle.

  • Error Code Meaning: Plain-language explanation of the specific DTC fault.

  • Causes & Suggestions: Recommended troubleshooting steps and potential root causes to assist your service team.

For additional assistance with diagnostic error codes, contact support@fleetr.app or call (1) 415-651-7575.