Clearing Diagnostic Trouble Codes (DTCs), also known as fault codes, is a common task for automotive technicians. But what about permanent DTCs? Can an Autel professional scan tool clear these codes? This article delves into the complexities of DTCs, permanent codes, and the capabilities of Autel scan tools in managing them.
Understanding DTCs and Permanent Codes
DTCs are alphanumeric codes that represent specific malfunctions detected by a vehicle’s onboard diagnostic system (OBD). The OBD system, mandated by US federal authorities around 1995 and adopted by the EU shortly after, standardized emission monitoring and diagnostics via a universal 16-pin connector. This system provides access to two types of information: publicly available OBD2/3 data and manufacturer-specific data, which is often restricted.
Faults are detected by monitors constantly scrutinizing various vehicle components. When a malfunction occurs, a pending code is set. If the issue persists, the code becomes a hard code, triggering the Check Engine Light (CEL). Clearing a DTC doesn’t necessarily fix the underlying problem. In fact, prematurely clearing codes can reset all system monitors, requiring extensive drive cycles to re-learn and close. This can be particularly problematic for emissions testing, as open monitors can lead to a failed test.
Permanent DTCs, a specific type of hard code, are stored in the Powertrain Control Module (PCM) even after the fault is resolved and the code is cleared. These codes are designed to record significant emissions-related issues for future diagnosis.
Autel Scan Tools and DTC Management
Autel offers a range of professional scan tools with varying capabilities. While basic code readers can retrieve generic OBD2/3 codes, Autel’s professional-grade tools provide more advanced functionalities, including bi-directional control, live data streaming, and access to manufacturer-specific data. These features allow technicians to not only read and clear codes but also to actively test components and perform diagnostics.
But can an Autel scan tool clear permanent DTCs? The answer is complex. While an Autel scanner can clear the DTC from the active fault list, it cannot erase the permanent record stored in the PCM. This record remains as a historical marker of the previous fault. However, if the underlying issue is resolved, and the monitor associated with the permanent DTC completes its drive cycle successfully, the CEL will remain off, and the vehicle should pass emissions testing.
Choosing the Right Autel Scan Tool
Selecting the right Autel scan tool depends on your specific needs and budget. Factors to consider include vehicle coverage, diagnostic capabilities, and software features. Autel offers a range of options, from entry-level models to high-end diagnostic platforms. Researching specific model features and comparing them to your requirements is crucial for making an informed decision.
Conclusion
While an Autel professional scan tool can clear active DTCs, including those that have transitioned to permanent status, it cannot erase the permanent record of the fault from the PCM. However, addressing the underlying issue and completing the necessary drive cycles can ensure the CEL stays off and the vehicle passes emissions tests. Choosing the right Autel scan tool is paramount for effective diagnostics and repair. Consider your specific needs and budget when selecting a model. Investing in a quality scan tool, like those offered by Autel, can significantly enhance your diagnostic capabilities and contribute to efficient vehicle repair.
