Understanding the capabilities of an OBD2 scanner can be crucial for car owners and mechanics alike. A common question is whether a code reader can rewrite or clear codes, particularly concerning models like the AL329. While the AL329 excels at reading and diagnosing trouble codes, it typically does not have the functionality to rewrite the underlying software or firmware of a vehicle’s Engine Control Unit (ECU). This article explores the functionalities of various OBD2 scanners, including code readers and advanced diagnostic tools, and discusses their ability to read, clear, and potentially modify vehicle codes.
Understanding OBD2 Scanners: From Basic to Advanced
The market offers a wide array of OBD2 scanners, ranging from simple code readers to sophisticated professional-grade devices. Basic code readers, often priced under $100, provide the functionality to read and clear Diagnostic Trouble Codes (DTCs). These tools are helpful for identifying the source of a “Check Engine Light” and can be sufficient for basic troubleshooting.
More advanced scanners, also known as bidirectional scan tools, offer a wider range of functions. These include:
- Live Data Streaming: Monitoring real-time sensor data.
- Active Tests: Commanding specific components to activate for diagnostic purposes.
- Key Programming: Programming new keys or remotes.
- ECU Coding and Programming: Modifying certain vehicle parameters within the ECU.
These advanced functionalities come with a higher price tag, typically ranging from several hundred to thousands of dollars. Tools like the Autel MK808S, priced around $400, offer comprehensive system diagnostics, active test capabilities, and certain coding functions. For professional mechanics, high-end scanners like the Snap-on Verus Edge provide even more advanced features but are significantly more expensive.
alt text: Advanced bidirectional scan tool Autel MK808S
Rewriting Code with OBD2 Scanners
While clearing codes is a standard feature in most OBD2 scanners, rewriting the actual code within the ECU is a different matter. Rewriting code requires specialized software and hardware and is generally performed by trained professionals. Some high-end bidirectional scanners, like certain Autel and Launch models, offer limited ECU coding capabilities. However, these functionalities are typically restricted to specific vehicle makes and models and often require specialized training and knowledge.
Affordable Options for Comprehensive Diagnostics: Thinkdiag
For DIY enthusiasts and budget-conscious users, the Thinkdiag offers a compelling option. Priced around $100, this Bluetooth dongle connects to a smartphone or tablet, providing access to full system diagnostics and bidirectional control. While it requires a yearly subscription for enhanced functions, it still offers significant value for its price. However, experiences may vary with specific vehicle makes, as compatibility and performance can differ.
Choosing the Right OBD2 Scanner
The choice of an OBD2 scanner depends on individual needs and budget. For basic code reading and clearing, a simple code reader suffices. For more in-depth diagnostics and advanced functions like active tests and some coding capabilities, a bidirectional scan tool like the Autel MK808S or the Thinkdiag offers a viable solution. Before purchasing, research the specific functionalities of each scanner and ensure compatibility with your vehicle make and model. Consider factors like software updates, user interface, and customer support when making your decision.
Conclusion: Matching Your Needs to Scanner Capabilities
Understanding the distinction between reading, clearing, and rewriting codes is essential when choosing an OBD2 scanner. While most scanners can read and clear codes, rewriting ECU code typically requires specialized equipment and expertise. The market offers a wide range of options, from basic code readers to advanced bidirectional scan tools, catering to varying needs and budgets. Thorough research and consideration of individual requirements will help you select the right OBD2 scanner for your specific automotive diagnostic needs.
