For owners and technicians dealing with a 2000 Dodge Durango 5.9L undergoing a smog test, understanding the On-Board Diagnostic (OBD2) system and its reports is crucial. This guide provides a detailed overview of OBD2 smog test standards, specifically addressing potential issues and interpretations relevant to your 2000 Durango 5.9L. We’ll delve into pass/fail criteria, common problems, and how to interpret OBD2 reports to ensure your Durango passes its smog check.
Understanding OBD Smog Test Standards for Your 2000 Durango 5.9L
The OBD system in your 2000 Durango 5.9L is designed to monitor the performance of emission control components. During a smog test, the OBD system is checked to ensure it’s functioning correctly and that your vehicle is meeting emission standards. Here’s a breakdown of the key aspects of the OBD test you need to be aware of:
Readiness Monitors: Are They Set?
Readiness monitors are self-tests that the Durango’s computer performs to verify that the emission control systems are working. For a 2000 gasoline vehicle like your Durango 5.9L, passing the OBD test requires that most, but not all, of these monitors are in a “ready” state.
According to standard OBD test guidelines:
| Model Year | Fuel Type | Number of Incomplete Monitors Allowed to Pass OBD Test |
|---|---|---|
| 1996-1999 | Gas | Any one |
| 2000 and newer | Gas | Evaporative system |
| 1998-2006 | Diesel | Zero |
| 2007 and newer | Diesel | Particulate Filter and Non-Methane HydroCarbon (NMHC) |
For your 2000 Durango 5.9L (Gas), this means that to pass the smog test, only the Evaporative system monitor can be incomplete. All other monitors should ideally be set to “ready”. The misfire, fuel, and comprehensive component continuous monitors are typically ignored during the OBD test for gasoline vehicles.
The OBD-II port, usually located under the dashboard, is where smog check technicians connect scan tools to retrieve OBD2 reports during a smog test.
If your Durango fails the smog test due to unset readiness monitors (other than evaporative), it might indicate:
- Recent Battery Disconnection or Code Clearing: Readiness monitors reset when the battery is disconnected or codes are cleared. You’ll need to drive your Durango through a specific drive cycle to allow these monitors to reset.
- Underlying Emission System Issues: If monitors are consistently not setting, there might be a fault in one of the emission control systems preventing the self-tests from completing.
Malfunction Indicator Lamp (MIL): Check Engine Light Status
The Malfunction Indicator Lamp (MIL), often called the “Check Engine” light, is a critical indicator during the smog test. Here are the pass/fail standards related to the MIL for all OBDII vehicles, including your 2000 Durango 5.9L:
| Condition | Pass/Fail | Standard |
|---|---|---|
| MIL illuminates when key on engine off (KOEO) | Pass | Indicates the MIL bulb is working |
| MIL turns off when engine running (KOER) | Pass | Indicates no active emissions faults |
| MIL does not illuminate when key on engine off (KOEO) | Fail | Indicates a problem with the MIL bulb or circuit |
| MIL illuminates when engine running (KOER) | Fail | Indicates active emissions faults are present |
If your 2000 Durango 5.9L has the MIL illuminated while the engine is running, it will automatically fail the OBD portion of the smog test. This signifies that the OBD system has detected one or more emission-related problems. You’ll need to retrieve the Diagnostic Trouble Codes (DTCs) to diagnose and repair the issue.
Communication Standards: Can the Smog Machine Talk to Your Durango?
For a successful OBD smog test, the smog check equipment must be able to communicate with your 2000 Durango’s computer. Communication issues can lead to a test failure.
| Test Type | Standard |
|---|---|
| BAR-97 | Vehicle communicates with BAR-97 equipment. |
| OIS | Vehicle communicates with OIS and transmits required data. |
“No communication” failures can occur due to several reasons:
- Damaged OBD Connector or Wiring: Inspect the OBD connector under your dashboard for damage and check for any issues with the wiring leading to it.
- Aftermarket Stereo or Accessories: Sometimes, aftermarket electronics can interfere with OBD communication.
- Vehicle Computer Problems: In rare cases, issues with the vehicle’s computer itself can prevent communication.
For older vehicles like the 2000 Durango, ensuring a clean and functional OBD port is the first step in troubleshooting communication issues.
Permanent Diagnostic Trouble Codes (PDTCs): Are There Any Lingering Issues?
Permanent Diagnostic Trouble Codes (PDTCs) are a type of DTC that, once set, cannot be cleared by simply using a scan tool or disconnecting the battery. They are designed to ensure that a vehicle has truly completed the repair for an emission issue and verified it over time.
| Model Year | Test Type | Standard |
|---|---|---|
| 1996-1999 | BAR-97 | Not applicable. |
| 2000-2009 | OIS | Not applicable. |
| 2010 and newer | OIS | Vehicles fail when a PDTC is present. |
For a 2000 Durango 5.9L, PDTCs are not applicable for smog test failure. PDTC checks were implemented for 2010 and newer vehicles. However, understanding DTCs in general is still important for diagnosing any MIL illumination issues.
Specific OBD Test Considerations for 2000 Durango 5.9L
While the original document doesn’t list specific issues for the 2000 Dodge Durango 5.9L, considering vehicles of similar era and manufacturer can be helpful. For instance, the document mentions some Dodge Ram trucks from the late 90s and early 2000s having issues with continuous monitors not completing.
A well-maintained engine bay in a 2000 Dodge Durango 5.9L can contribute to passing a smog test by ensuring all emission components are in good working order.
Based on the general information and considering the age of a 2000 Durango 5.9L, potential issues to watch out for include:
- Readiness Monitor Completion: Ensure you perform a proper drive cycle after any repairs or battery disconnection to set the readiness monitors. If monitors are not setting, diagnose potential issues with the related emission systems (e.g., EVAP system, oxygen sensors).
- MIL Illumination: Address any “Check Engine” light issues before the smog test. Retrieve DTCs, diagnose the root cause, and perform necessary repairs. Common culprits for older vehicles can include issues with oxygen sensors, catalytic converters, or EVAP system leaks.
- OBD Communication: While less common, communication issues can occur in older vehicles due to connector corrosion or wiring problems. Ensure the OBD port is clean and functional.
Interpreting OBD2 Reports for Smog Test
When your 2000 Durango 5.9L undergoes a smog test, the OBD2 report will typically provide information on:
- Readiness Monitor Status: Indicates whether each supported monitor has been completed (“ready”) or not (“not ready”).
- MIL Status: Shows if the MIL is commanded ON or OFF.
- Diagnostic Trouble Codes (DTCs): Lists any stored DTCs, including pending and confirmed codes.
- Permanent Diagnostic Trouble Codes (PDTCs): (Though not applicable for failure for 2000 models, their presence can still indicate past issues).
For a Pass Result on your 2000 Durango 5.9L:
- Readiness Monitors: All applicable monitors should be “ready” except for possibly the Evaporative system monitor.
- MIL Status: MIL should be OFF when the engine is running (KOER).
- DTCs: No active DTCs should be present.
For a Fail Result, the OBD2 report will pinpoint the reason, such as:
- MIL ON: Indicates emission system fault(s). DTCs will need to be diagnosed and repaired.
- Excessive Incomplete Monitors: More than the allowed incomplete monitors are not set to “ready”.
- Communication Failure: Smog equipment could not communicate with the vehicle’s OBD system.
Conclusion: Ensuring Your 2000 Durango 5.9L Passes the Smog Test
Understanding the OBD2 system and smog test requirements is essential for 2000 Durango 5.9L owners. By checking readiness monitors, addressing any MIL illumination, ensuring OBD communication, and understanding the OBD2 report, you can proactively address potential issues and increase the chances of your Durango passing its smog test. Remember to consult a qualified mechanic for diagnosis and repair of any emission-related problems to keep your Durango running cleanly and legally.
