1. 1 Triggers for OBDII I/M Programs Rob Klausmeier dKC

2. 2 What Are Triggers? Triggers are reports to identify stations performing fraudulent or inaccurate inspections. Triggers can be grouped into the following categories: –High Probability Clean-Scanning Triggers, –Triggers to Identify Facilities with out-of- range inspection results

3. 3 High Probability Clean-Scanning Triggers Mismatch between expected and actual OBDII parameters. Questionable Retests – Short time between failing and passing tests Questionable Retests – Mismatch between initial test OBDII parameters and retest OBDII Parameters

4. 4 OBD Parameter Mismatch Report can identify mismatches between OBDII parameters for vehicle entered into inspection record and parameters downloaded from OBDII system % of vehicles with different OBDII parameters: –Monitors supported – 100% –Communication protocol – 100% –PID Count – 100% –PCM ID – 100% –PCM VIN – 16.8% –Calibration ID (CAL ID) – 34.9% –Calibration Verification number (CVN) – 34.6%

5. 5 % of Vehicles Reporting CAL ID, CVN and PCM VIN Model Year CAL IDCVNPCM VIN 1996-19990.00% 200046.25%43.00%13.13% 200177.52%79.65%42.58% 200291.39%90.38%47.43% ALL34.93%34.59%16.82%

6. 6 OBD Parameter Mismatches Currently, the only parameter that can positively identify clean scanning on initial tests is PCM VIN. A look-up table should be developed to identify the following for specific years, makes and models. –Monitors supported, –Communication protocol, –PID Counts, –PCM IDs, –CAL IDs, –CVNs

7. 7 PCM VIN Mismatches Identify mismatches between entered VIN and PCM VIN. Inspectors may be attempting to pass vehicles with OBDII faults by scanning problem free vehicles instead of vehicles that should be inspected. –If the vehicle has an electronic VIN available through the vehicle’s OBDII system, clean scanning cases can be identified by comparing entered VIN with VIN provided by vehicle’s OBDII system. –PCM VINs need to be manipulated to accurately identify mismatches. For example, dKC recommends comparing last 5 VIN digits.

8. 8 High Probability Clean-Scanning Triggers – Questionable Retests Trigger reports can identify questionable “fail previous test” / “pass next test” pairs. –Short-Time between failing and passing tests –OBD Parameter mismatches on retest passes

9. 9 Short Time Between Failing and Passing Inspections It is difficult to repair OBD failures and get failing vehicles to pass in a short time period: –MIL-On Fails – It takes time for the MIL to go off or readiness monitors to reset if codes are cleared –Readiness Fails – It takes time for readiness monitors to set to ready. Stations that often show short time periods between initial test failures and retest passes could be performing fraudulent inspections.

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11. 11 Questionable Retests Mismatch in OBDII Parameters Mismatch between initial test OBDII parameters and retest OBDII Parameters: –Supported readiness monitors –COM Protocol –PID/PCM identifiers –CAL ID –CVN –PCM VIN Mismatches between initial tests and retests could indicate that the inspector clean-scanned vehicles on retests.

12. 12 Readiness Monitor Mismatch

13. 13 Triggers To Identify Facilities With Out- Of-Range Inspection Results Too low or too high normalized failure rates Too low or too high KOEO failure rates Too low or too high DLC failure rates

14. 14 Too Low or Too High Normalized Failure Rates Too low or too high failure rates indicate possible fraudulent activities or equipment problems. Normalized fail rates can be calculated as follows: Compute overall initial test OBDII failure rate (all facilities) by model year. Tabulate percentage breakdown of initial OBDII tests by facility by model year. Weight the overall failure rate by model year by the percentage breakdown for each facility by model year. Compute the differences by facility between the actual failure rate and the normalized failure rate. Adjust differences by standard deviation.

15. 15 Normalized Fail Rates

16. 16 Out-Of-Range Inspection Results High KOEO or DLC Fail Rates Stations/Inspectors with a high percentage of failures due only to MIL not on during KOEO. Stations/Inspectors with a high percentage of DLC not found or damaged.

17. 17 Triggers Summaries Triggers should be tabulated by station. Stations with more than one minor trigger or any major trigger, e.g. Large emission reductions in a short time period, should be visited more frequently. Many stations have >1 Trigger. About ¾ of the trigger incidences are in stations that had >1 Trigger.

18. 18 Conclusions Trigger reports are being generated frequently to identify stations performing improper inspections.