This comprehensive guide outlines the pass/fail criteria for the OBD test during a Smog Check inspection and provides instructions for inspecting vehicles known to have OBD test issues. It focuses on utilizing an Auto Drive Obd2 Eobd Code Reader Application for diagnostics and troubleshooting.
Understanding OBD Pass/Fail Standards
This section summarizes the pass/fail standards for the On-Board Diagnostic (OBD) test, a crucial component of the Smog Check inspection. Using an auto drive OBD2 EOBD code reader application can significantly aid in understanding these standards and diagnosing potential issues.
Readiness Monitor Standards
Readiness monitors are self-diagnostic tests performed by the vehicle’s OBD system. They confirm the proper functioning of emission control components. Achieving readiness can be challenging for some vehicles due to specific driving conditions required or infrequent use in necessary operating modes. An auto drive OBD2 EOBD code reader application can display the status of these monitors.
The table below indicates the allowable number of incomplete monitors for passing the OBD test:
| Model Year | Fuel Type | Number of Incomplete Monitors Allowed to Pass OBD Test |
|---|---|---|
| 1996-1999 | Gasoline1 | Any one2 |
| 2000 and newer | Gasoline1 | Evaporative system2 |
| 1998-2006 | Diesel | Zero |
| 2007 and newer | Diesel | Particulate Filter and NMHC3 |
1 Includes gasoline, propane, natural gas (CNG, LNG, LPG).
2 Misfire, fuel, and comprehensive component continuous monitors are ignored for gasoline vehicles.
3 Non-Methane HydroCarbon (NMHC).
Malfunction Indicator Lamp (MIL) Standards
The MIL, often called the “Check Engine” light, provides crucial information about the vehicle’s emission system. An auto drive OBD2 EOBD code reader application can interpret the MIL status and retrieve associated trouble codes. Here’s a summary of MIL-related pass/fail criteria:
| Vehicle | Pass/Fail | Standard |
|---|---|---|
| All with OBDII | Pass | MIL illuminates when Key On Engine Off (KOEO). |
| All with OBDII | Pass | MIL turns off when Key On Engine Running (KOER). |
| All with OBDII | Fail | MIL does not illuminate when KOEO. |
| All with OBDII | Fail | MIL illuminates when KOER. |
Communication Standards
Effective communication between the OBD system and the auto drive OBD2 EOBD code reader application is essential for accurate diagnostics. Communication failures can stem from various factors, including a damaged OBD connector, wiring issues, or incompatible aftermarket components.
| Vehicle | Standard |
|---|---|
| All with OBDII | Vehicle communicates with the code reader and transmits required data.1 |
1 Required data typically includes Mode $01 PID $00 (supported data) and Mode $01 PID $01 (MIL status, DTCs, monitor status).
Permanent Diagnostic Trouble Code (PDTC) Standards
Implemented in July 2019, the PDTC check is an important aspect of the Smog Check inspection. PDTCs, similar to regular Diagnostic Trouble Codes (DTCs), indicate persistent emission-related faults. Unlike DTCs, PDTCs cannot be erased by simply clearing codes or disconnecting the battery. An auto drive OBD2 EOBD code reader application capable of reading PDTCs is necessary for identifying these persistent issues.
| Model Year | Standard |
|---|---|
| 1996-2009 | Not applicable. |
| 2010 and newer1 | Vehicles fail when a PDTC is present.2 |
1 Some 2010 vehicles may not support PDTC.
2 Certain exceptions and specific vehicle issues are detailed in Section E of this document.
Modified Software Standards
Since July 2021, the Smog Check inspection includes a modified software check. Software modifications approved by the California Air Resources Board (CARB) should not result in a failed inspection. An auto drive OBD2 EOBD code reader application might be able to detect certain software modifications, but confirming CARB approval often requires further investigation. Vehicles with illegally modified software will fail the inspection.
Vehicles of Interest and Troubleshooting with an Auto Drive OBD2 EOBD Code Reader Application
Sections D, E, and F of this document provide detailed information about specific vehicle makes, models, and years known to have OBD-related issues. These sections are invaluable resources for technicians using an auto drive OBD2 EOBD code reader application to diagnose and troubleshoot these common problems. The tables outline the issues, potential causes, remedies, and instructions for inspectors. Consulting these sections when encountering a problematic vehicle can save valuable time and ensure accurate diagnosis.
Conclusion
Utilizing an auto drive OBD2 EOBD code reader application is crucial for understanding and addressing OBD-related issues during Smog Check inspections. This guide provides a framework for interpreting OBD data, understanding pass/fail standards, and troubleshooting common vehicle problems. By combining the information presented here with the capabilities of a quality code reader, technicians can efficiently and accurately diagnose emission-related concerns, ensuring compliance with regulations and contributing to cleaner air. Always refer to the specific vehicle information in Sections D, E, and F for detailed guidance on known issues and recommended solutions.
