Diagnostic trouble code (DTC)

Glossary / Fleet maintenance / Diagnostic trouble code (DTC)

A diagnostic trouble code (DTC) is a code generated by a vehicle’s onboard computer system to indicate an issue or malfunction in the vehicle. The DTC system is an important diagnostic tool used to help identify and repair problems related to the engine, transmission, and other vehicle systems.

The DTC system monitors various sensors and systems throughout the vehicle and compares their readings to predetermined thresholds or values. If a sensor or system is found to be outside of its normal operating range, the onboard computer will generate a DTC code that corresponds to the specific issue or malfunction.

DTC codes are typically displayed on a vehicle’s dashboard or other diagnostic interface and can be read using specialized diagnostic equipment. The codes are typically composed of a series of letters and numbers that indicate the specific issue or malfunction that has been detected.

The DTC system enables technicians to quickly identify and diagnose issues with a vehicle. This can help to reduce downtime and improve the overall efficiency of the fleet operation. Additionally, the DTC system can help to improve safety by identifying potential issues before they become serious problems.

Integrating the vehicle’s onboard DTC system with fleet management software can
streamline fleet maintenance and support operational efficiency.

Learn more about Maintenance solutions from Motive

Frequently Asked Questions

DTC stands for diagnostic trouble code, which is a code generated by a vehicle’s onboard computer system to indicate a problem or malfunction. When a problem is detected, the computer generates a code that can be read by a diagnostic tool to help identify the issue. DTC codes can range from minor issues to more serious problems that require immediate attention.

Integrating the DTC system with an
AI-powered fleet management software, fleet managers can set up alerts for critical codes and simplify maintenance scheduling across a fleet.

A DTC (diagnostic trouble code) is caused by a fault in a vehicle’s system or component. The fault is detected by the onboard computer system, which then generates a specific code to indicate the problem. DTCs can be triggered by a wide range of issues, including faulty sensors, electrical problems, engine misfires, and more. Accurately identifying and repairing the underlying cause of a DTC is crucial for maintaining the vehicle’s performance and preventing further damage.

Motive’s fleet management software, you can see in your dashboard DTC notifications automatically prioritized by severity.

There are currently over 5,000 diagnostic trouble codes (DTC) that serve as a method for diagnosing and identifying issues with the various systems and components within a vehicle. DTC codes are standardized across manufacturers and are essential in providing technicians with a clear understanding of the problems they need to address.

fleet management software also helps managers make decisions by automatically prioritizing DTCs by severity.

To clear a diagnostic trouble code (DTC) after maintenance, you will need an OBD-II scanner. Plug the scanner into your vehicle’s OBD-II port, which is usually located below the dashboard. Turn on the scanner and follow the instructions to clear any stored DTCs. Once the codes are cleared, the scanner will display a message indicating that the operation was successful. Note that clearing DTCs will also reset any vehicle settings, including the radio presets and clock.