OBD II Workshop P roposed changes Mobile Source Control Division California Air Resources Board July 18, 2001 El Monte, California.

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OBD II WorkshopProposed changesMobile Source Control Division California Air Resources BoardJuly 18, 2001El Monte, CaliforniaDiscussion PointsNew technical requirementsCatalystMisfireEvaporative leak checkSecondary Air and Cold Start StrategyAir Conditioning systemVariable Valve TimingDORDiesel Catalyst and PM trapDiscussion PointsStandardization items for I/M and service techniciansDDV TestingProduction Vehicle TestingRate-based monitoringDeficienciesEnforcement ProvisionsNOx Catalyst MonitoringCurrently, only HC conversion efficiency required to be monitoredHowever, recent tailpipe standard reductions primarily target NOx (e.g. LEV II program)Current data indicates NOx emissions can vary from < 1x to > 3x standard when HC conversion efficiency threshold is reachedNOx- NMOG vs std1.25442982460.40.521.120.68333333330.120.28666666670.65666666671.341.451.23333333331.91111111111.850.53333333330.68000.96666666670.26666666671.241.83333333330.80.86333333330.15833333330.05001.19333333330.98833333332.251.161.99833333331.46666666670.16666666672.52.56666666672.150.5960.5822.3621.793333333300.91.73666666670.51.92.880.86666666671.56666666670.67666666671.66666666673.4NOX/StdNMOG/StdNOx/StdDDV data with "threshold" NMOG catalystNMOG-NOx vs baseline00001.1134020619-0.14285714290.08860759491.345238095202.6250.85001.666666666702.37162162161.5494071146000.77142857141.391304347800000002.35028248592.751.52173913045.62430939234.827814569506.55.41666666676.37142857142.31111111111.3095238095000019.038461538500000000NMOG MultipleNOx MultipleThreshold Catalyst NOx/NMOG Correlation catalyst dataCatalyst DataBaseline DataManufacturerMYEngine FamilyModelStdCat MonNMHC/NMOGCONOXNMOG StdNOX StdNMOG/StdNOX/StdNMHC/NMOGCONOXNMOG % IncreaseNOx % IncreaseCommentBMW99XBMXV02.8LEVLEV0.121.340.440.090.31.31.30.0000.000BMW0YBMXV05.4LEVLEV2.5xstd+4k0.1742.760.120.090.31.90.40.0000.000DaimlerChrysler98LEV/LDT20.1481.790.260.130.51.10.50.0000.000DaimlerChrysler99Grand CherokeeLEV/LDT22.5xstd+4k0.2793.370.560.130.52.11.10.0000.000DaimlerChrysler0NeonULEV1.75xstd0.0871.2820.2050.0550.31.60.70.0510.4840.0970.7061.113DaimlerChrysler11CRXT0242240Grand CherokeeULEV/LDT21.75xstd0.0451.250.060.130.50.30.10.0380.5300.0700.184-0.143Daewoo99XDWXV02.0D02LEV0.0691.4740.0860.090.30.80.30.0620.8310.0790.1200.089Baseline 100k cert valuesDaewoo0LEV0.0710.4710.1970.090.30.80.70.0480.3810.0840.4791.345Ford97VFM2.0V8G2EKEscortTLEV0.1775.260.8040.1560.61.11.30.0000.000ARB testFord11FMXT04.6PF6F-150LEV/MDV21.75xstd0.3013.730.870.230.61.31.50.0810.5200.2402.6982.625GM99XGMXV03.1043LEV1.75xstd0.1423.740.370.090.31.61.20.0531.0000.2001.6790.850Baseline 100k cert valuesGM98LEVMDV32.5xstd+4k0.3428.431.720.280.91.21.90.0000.000GM97VGM1.9VJG2JKTLEV2.0xstd+4k0.2734.851.110.1560.61.81.90.0000.000Honda98WHNXV02.3PL4AccordULEV1.75xstd0.061.890.160.0550.31.10.50.0280.3000.0601.1431.667Baseline 100k cert valuesHonda99XHNXT03.5EA3OdysseyLEV/LDT21.75xstd0.1111.710.340.130.50.90.70.0000.000LDT2?Isuzu11SZXT02.22LK0.091.950.4990.00.00.0770.7500.1480.1762.372Isuzu22SZXT03.52KK0.09734.120.6450.00.00.0901.7400.2530.0841.549Jaguar11JCXV04.0BN4LEV2.5xstd+4k0.1681.760.290.090.31.91.00.0000.000Kia0LEV0.090.630.080.090.31.00.30.0000.000Mazda0MPVLEV/LDT21.75xstd0.2121.530.620.130.51.61.20.1091.0800.3500.9450.771Mazda99ProtgULEV3.0xstd+4k0.1710.990.550.0550.33.11.80.0480.8400.2302.5631.391Mazda1626ULEV3.0xstd+4k0.1570.760.240.0550.32.90.80.0420.7600.2402.7380.000Mercedes98WMBXV03.2GNBLEV1.75xstd0.1371.530.2590.090.31.50.90.0000.000Mercedes99XMBXT04.3GNBLEV/MDV22.5xstd+4k0.2472.780.0950.230.61.10.20.0000.000Mercedes11MBXT03.21BLULEV/MDV21.75xstd0.1252.220.030.1430.60.90.10.0000.000Mitsubishi99DiamanteLEV2.5xstd+4k0.182n/an/a0.092.00.00.0000.000Mitsubishi11DSXV02.4GNGULEV1.75xstd0.061n/an/a0.0551.10.00.0000.000Nissan97VNS1.6VJG3EKSentraLEV2.5xstd+4k0.1330.8740.3580.090.31.51.20.0000.000ARB testNissan99XNSXV03.026ATLEV1.75xstd0.2461.530.5930.1560.61.61.00.1021.0000.1771.4122.350Nissan0YNSXV01.85BASentra CASULEV1.75xstd0.01140.50.0450.010.021.12.30.0050.1100.0121.1922.750Nissan11NSXT03.5C7AQX4LEV/LDT21.75xstd0.09611.460.580.130.50.71.20.0501.1100.2300.9381.522Porsche99XPRXV03.4996911Tier 10.4755.4631.1990.310.61.52.00.0510.6760.1818.3145.624ARB TestPorsche99XPRXV03.4996911Tier 10.5284.280.880.310.61.71.50.0920.6220.1514.7394.828Porsche11PRXV03.6TUR911 TurboLEV0.1292.60.050.090.31.40.20.0000.000Subaru99XFJXV02.2FEFLEV0.1783.90.750.090.32.02.50.0610.7100.1001.9186.500Subaru0YFJXV02.5JEHLegacyLEV1.75xstd0.1413.380.770.090.31.62.60.0480.8500.1201.9385.417Suzuki98WSKXV1.59TNSEsteemTLEV2.0xstd+4k ??0.2633.061.290.1560.61.72.20.1071.5580.1751.4586.371Suzuki0YSKXT2.00LMAVitaraLEV0.1220.6570.2980.130.50.90.60.0520.2010.0901.3462.311Suzuki11SKXT2.49LC1Grand VitaraLEV/LDT2 ??0.1332.7060.2910.130.51.00.60.0690.8280.1260.9281.310Toyota99XTYXT03.4GXStruckLEV/LDT21.75xstd0.1751.991.1810.130.51.32.40.0000.000Toyota97VTY2.2VJG3GKCamryLEV2.5xstd+4k??0.1782.090.5380.090.32.01.80.0000.000Toyota0YTYXV02.2JJBULEV1.75xstd0.093n/an/a0.0551.70.00.0000.000Toyota11TYXV01.5LJ1SULEV5.0 x std. ??0.02730.970.0180.010.022.70.90.0000.000Is the NMOG data correct?Volvo98XVVXV2.9EVATier 10.2374.7961.0420.310.60.81.70.1371.9880.0520.73019.038ARB testVolvo97VVV2.4VJGKEKTLEV2.0xstd+4k0.1362.040.30.1560.60.90.50.0000.000Volvo98WVVXV2.43TPFTLEV2.0xstd+4k0.2173.951.140.1560.61.41.90.0000.000Volvo11VVXV02.43U5NULEV1.75xstd0.0742.1840.8640.0550.31.32.90.0000.000VW99XVWXV02.0227Beetle, Golf, JettaLEV0.1672.960.260.090.31.90.90.0000.000VW98WVWXV02.0226New BeetleTLEV0.2044.260.940.1560.61.31.60.0000.000VW98WVWXV02.0226New BeetleTLEV0.1323.0840.4060.1560.60.80.70.0000.000ARB testVW0YADXV02.7333TLEV1.75xstd0.1420.6610.1560.60.91.70.0000.000VW11ADXV01.8342ULEV3.0xstd+4k0.1653.731.020.0550.33.03.40.0000.000Average1.41.2&COBD II Catalyst DDV DataSheet2Sheet3NOx Catalyst MonitoringOriginal ProposalStaff proposal would require 2007 and subsequent LEV II program vehicles to indicate a catalyst malfunction before HC or NOx conversion efficiency reaches 1.75x standard (2.5x for SULEVs)2005 and 2006 LEV II program vehicles would use an interim threshold of 3.5x NOx standardExpect most manufacturers to meet requirement with refinement of existing oxygen storage monitoring methodNOx Catalyst MonitoringRevised ProposalStaff proposal would require 2007 and subsequent LEV II program vehicles to indicate a catalyst malfunction before HC or NOx conversion efficiency reaches 1.75x standard (2.5x for SULEVs)30% of 2005 and 60% of 2006 LEV II program vehicles would use an interim threshold of 3.5x NOx standardExpect most manufacturers to meet requirement with refinement of existing oxygen storage monitoring methodOther Catalyst ChangesChanges would require aging of both monitored and unmonitored catalysts when developing threshold catalyst calibrations on 2005 and subsequent LEV II program vehicles not using fuel shut-off during misfireChanges would allow monitored catalyst volume to have lower than 50% conversion efficiency if packaged/replaced with additional catalyst volume that, in total, exceeds 50% conversion efficiencyMisfire MonitoringChanges would identify more specifically what type of disablements are generally approved by ARBChanges would identify what type of disablements will no longer be allowed in 2005 and subsequent model years(A/C compressor cycling, A/T gear shifts, idle to off-idle transitions, load or speed transients less severe than US06 cycle, etc.)Misfire Monitoring (cont.)Clarify for 2005 and subsequent vehicles, conditions when individual vs. multiple cylinder fault codes should be storedAllow disablement at engine start for no longer than 2 crankshaft revolutions after meeting the engine start definitionSet minimums of 1% and 5% for FTP and catalyst damage misfire levels, respectivelyAllow down to 75% probability of detection during cold start strategy operationEvaporative System MonitoringCurrently, purge valve functional check, 0.040 leak detection, and 0.020 leak detection required on all 2003 model year vehiclesEngine-off diagnostics that do not meet a conventional two-in-a-row definition not accounted for very well.Evaporative System Monitoring (cont.)Proposal would more explicitly allow non-conventional (e.g., engine-off) diagnosticsProposal would provide further specification on the shape of the orificeIntent of proposal to allow manufacturers with frequent 0.020 monitors to conduct gross leak (>0.090) in lieu of 0.040 monitoringEvaporative System Monitoring (cont.)Regarding frequency of 0.020 monitor, many manufacturers have made tremendous improvements from the 2000 to 2002 model yearWhile very restrictive enable conditions were originally necessary, further refinements now appear to allow much broader conditionsAccordingly, proposal does not account for as severely constrained monitoring conditions as originally adopted in 1996Evaporative System Monitoring (cont.)Proposal:Detect 0.040 in two weeksDetect 0.020 in three weeksPerform 0.090 in lieu of 0.040 if and only if:Detect 0.020 in two weeksDetect 0.090 in one weekSecondary Air and Cold Start Strategy MonitoringVast majority of emissions occur at cold startMany emission control components and strategies focused on accelerating catalyst warm-upCurrently, these components are generally monitored for proper performance only after the vehicle is warmed-upSecondary Air SystemOriginal ProposalChanges would require 2007 and subsequent LEV II program vehicles to monitor the secondary air flow rate during cold start for malfunctions that cause emissions to exceed 1.5x standard (2.5x for SULEV)2005 and 2006 LEV II program vehicles would be required to perform a functional check (e.g., flow or no flow) during cold start and a 1.5x standard flow rate check later in the same driving cycleMost likely monitoring method appears to use a wide-range A/F sensor (in lieu of a conventional O2 sensor)Secondary Air SystemRevised ProposalChanges would require 2007 2008 and subsequent LEV II program vehicles to monitor the secondary air flow rate during cold start for malfunctions that cause emissions to exceed 1.5x standard (2.5x for SULEV)2005 and 2006 and 2007 LEV II program vehicles would be required to perform a functional check (e.g., flow or no flow) during cold start and a 1.5x standard flow rate check later in the same driving cycleCold Start Strategy MonitoringOriginal ProposalChanges would require 2005 and subsequent LEV II program vehicles to monitor the key control and feedback parameters during cold start for malfunctions that cause emissions to exceed 1.5x standard (2.5x for SULEV)Most likely monitored parameters are engine speed, idle air mass flow, and commanded spark timingCold Start Strategy MonitoringRevised ProposalChanges would require 2005 and subsequent LEV II program 30/60/100% in 2006/07/08 vehicles to monitor the key control and feedback parameters during cold start for malfunctions that cause emissions to exceed 1.5x standard (2.5x for SULEV)Cold Start Strategy Monitoring (cont.)Only requires malfunction detection when a single component malfunction or deterioration can cause emissions to exceed 1.5x standard (as opposed to a total system monitor).Allows manufacturers to calibrate to 1.5x standard on a representative vehicle and carry-over the thresholds to other vehicles (reducing calibration burden).Air Conditioning System Component MonitoringCurrently, all electronic powertrain components required to be monitored under comprehensive componentsSome are concerned this may currently include some A/C componentsIn general, staff does not believe it should be necessary to monitor A/C components under the OBD II requirements Air Conditioning System Component Monitoring (cont.)Proposal would exclude electronic A/C components from monitoring unless:Failure causes emissions to exceed 1.5x applicable standard (FTP for A/C physically off malfunctions, SC03 for A/C physically on malfunctions), orFailure effectively disables any other OBD II monitorBased on experience to date, it appears unlikely that any A/C system components will require monitoring30/60/100% phase-in in 2006/07/08 vehiclesVariable Valve Timing (VVT) System MonitoringIncreasing trend in industry to use some form of VVT system for improved performance without emission increaseEssentially performs as an EGR systemCurrently, the individual VVT components are monitored but the overall system performance is not monitored to a tailpipe emission levelVariable Valve Timing (VVT) ProposalChanges would require 2005 and subsequent LEV II program vehicles to monitor system performance to 1.5x standards (2.5x SULEV)Position errors and slow response malfunctions would need to be detectedMost systems already monitored for these failure modes but may need to be recalibrated to meet the emission thresholdsDirect Ozone Reduction (DOR)System MonitoringSome new emission reduction technologies have evolved that directly reduce ozoneExamples include specially coated radiators, etc. (e.g., PremAir)Requires unique solution because component does not directly affect vehicle tailpipe or evaporative emissions nor any other OBD II system monitorsDirect Ozone Reduction (DOR)System Monitoring (cont.)CARB policy was formalized in MAC No. 99-06 which outlined emission credits and monitoring requirementsAssigns different levels of emission credit (or offset) depending on monitoring capability (i.e., functional vs. performance)Optical, resistance, and ozone sensor monitoring technologies are fairly far into developmentDirect Ozone Reduction (DOR)System Monitoring (cont.)Changes would simply incorporate MAC policy officially into regulationWould also allow half-credit for 2003 and 2004 without any monitoringUniqueness of component (e.g., deterioration does not affect tailpipe/evaporative emissions or other monitors) merits special handlingOffset would also be carried over to other HC-based standards (e.g., 1.5x HC std + offset)Monitoring ThresholdsMany OBD II monitors calibrated to 1.5x FTP emission levelsAs the industry transitions to lower emission levels in the LEV II program, some have questioned the need for revisions to the 1.5x thresholdMonitoring Thresholds (cont.)Based on systems certified to date, staff does not believe LEV II and ULEV II standards necessitate special thresholdsLEV II/ULEV II have identical HC and CO standards as LEV I/ULEV I and only have lower NOxNOx is generally only the limiting pollutant for EGR, fuel system, and potentially O2 sensor responseProposed regulation does, however, retain flexibility to revise the thresholds if later found to be necessarySULEV Monitoring ThresholdsProposed revisions do increase the threshold for SULEV vehicles to 2.5x standard in lieu of 1.5x standardAccounts for increased uncertainty of todays emission measurement technology at SULEV levelsAnd, based on currently certified systems, appears to allow essentially identical levels of individual component deterioration as ULEV I levels.Diesel Vehicle Monitoring ChangesCurrently, diesel vehicles Diesel Catalyst Monitoring for MDVsChanges would require 2007 and subsequent MDVs to monitor catalysts for 1.5x standard failures of HC, NOx, or PMIf failure of component cannot cause 1.5x standard emission levels, functional monitoring requiredHowever, low efficiency catalysts (Diesel Catalyst Monitoring for MDVs Interim Proposal2005 and 2006 MDVs only required to detect 1.5x standard NOx or PM failures (not HC)If failure of component cannot cause 1.5x standard emission levels, no monitoring required (instead of functional monitoring)Diesel PM Trap Monitoring for MDVsChanges would require 2007 and subsequent MDVs to monitor PM traps for 1.5x standard failuresIf failure of component cannot cause 1.5x standard emission levels, only functional monitoring requiredExhaust backpressure sensor appears to be likely monitoring technologyConsistent with OBD regs [(a)(1.10)] that currently require other emission control devices to be monitoredDiesel Catalyst Monitoring for LDVsChanges would require 2004 and subsequent LDVs to monitor catalysts for 1.5x standard failures of HC, NOx, or PMIf failure of component cannot cause 1.5x standard emission levels, functional monitoring requiredHowever, low efficiency catalysts (Diesel PM Trap Monitoring for LDVsChanges would require 2004 and subsequent LDVs to monitor PM traps for 1.5x standard failuresIf failure of component cannot cause 1.5x standard emission levels, only functional monitoring requiredExhaust backpressure sensor appears to be likely monitoring technologyConsistent with OBD regs [(a)(1.10)] that currently require other emission control devices to be monitored Standardization changesAn essential part of OBD II is the standardization requirementsIncludes items like scan tool communication, connector, fault codes, etc.Based on feedback from the field and I/M programs, global standards, and technology improvements, updates to current standardization requirements are warranted. Changes to help I/M programsEPA recently modified the requirements for state I/M programs Inspection of the OBD II system a necessary element and can be done in-lieu of any tailpipe emission testingAccordingly, increasing focus on the performance of OBD II systems and ease of incorporation into an I/M programModifications to help I/M programs (cont.)EPAs decision considered the results of several test programs across the nationWhile the decision supports the performance of the OBD II system in identifying vehicles in need of emission repairs, plenty of room for improvement was identified in areas to ease implementation into an I/M programReadiness StatusOne area for improvement identified was readiness status/codesConceived primarily to identify recent attempts to erase the fault memory of the vehicleField experience has shown a higher than expected number of vehicles that indicate one or more monitors has not runReadiness Status (cont.)Vehicles not ready due to:Incorrect or overly restrictive software logicRecent repairsOverly restrictive monitoring conditionsDriver habitsAmbient conditionsReadiness Status (cont.)Proposal requires faster, consistent setting to complete on passing vehiclesAdditional data available via scan tool to distinguish recent fault code clearing from driver pattern or ambient condition situationsAdditional data (via scan tool and service info) to help technicians set readiness status in post-repair situationsAllow MIL to blink readiness status to vehicle owner without using a scan toolElectronic access to VINOne item commonly collected during an I/M check is the VINRequires entry by the inspector manually or via bar code scanningAccess to the VIN through the OBD II data connector simplifies and automates data collectionProposal requires access on all 2005 and newer vehiclesConnector locationManufacturers are currently provided abundant latitude in the location of the OBD II data link.Pilot I/M programs have demonstrated the need for further restrictions on connector locationProposal further confines connector to drivers footwellMIL bulb checkAll I/M programs continue to use a visual MIL check as part of the inspectionProposed changes require MIL to remain on for a minimum of 15-20 seconds during bulb check to help technicians properly verify bulb checkProposal clarifies that MIL command status (via the scan tool) should be OFF during bulb check to avoid mistakenly failing cars in I/MCommunication Protocol TestingOBD II vehicles required to use one of three allowable generic communication protocolsSome problems have been encountered during scan tool or I/M equipment designMany due to inappropriate interpretations of SAE and ISO standards or misunderstandingsResult is some vehicles are more difficult to talk to than othersCommunication Protocol Testing (cont.)Changes would require manufacturers to test representative vehicles at the end of the assembly lineCARB would contract out to have custom test equipment built exactly to ISO and SAE standardsVehicles unable to communicate with custom test equipment would require corrective actionShould minimize chance of future problems resulting in vehicles incompatible with I/M checkRepair Information ChangesOne consistent message received from the field is that technicians want access to more and more information for repairWhile OBD II has put more information in the hands of independent technicians than ever before, even more could be done.EPA, California legislators, and CARB have all taken steps to make more info availableAccess to InformationUnder a separate rulemaking, CARB is adopting a service information regulationWill require access to service info via InternetWill dictate that some information be made available such as monitoring conditions, drive cycles to execute monitors, etc.Due to Board Hearing timing differences between service info and OBD II regulation, service info provisions must remain in OBD II with escape clause once service info is adoptedAdditional Scan Tool DataBased on feedback from the field, 12-18 additional parameters proposed to aid in diagnosis and repair of vehiclesFurther specification added to two parameters (TPS and Load) to clean-up discrepancies in the way they are calculated and reportedProposal requires the new parameters on all 2005 and newer vehicles.New Communication ProtocolAllowance of a new protocol to keep pace with the developments on vehicles regarding communication between modulesController Area Network (CAN) will allow faster data update rates and provide more information to techniciansWill be allowed on 2003 and newer vehiclesProposed changes make it the only protocol allowed on 2008 and newer vehiclesFurther StandardizationChanges provide more direction to manufacturers for using generic (P0xxx) fault codes instead of manufacturer-specificChanges require consistent storing and erasing of pending fault codes on all 2005 and subsequent model year vehiclesProduction Vehicle Evaluation TestingEssentially, three new verification test sequences required on production vehiclesFirst verifies basic OBD II interaction with a generic scan tool (simulates an I/M OBD test)Second verifies, in detail, that every monitor functions as designed on a production vehicleThird requires the collection of in-use monitoring performance data from actual in-use cars within the first six months after production startsVerification of Standardized FunctionsRequires manufacturer to verify basic interaction with a generic scan tool on one vehicle per representative calibrationWould take effect one year after ARB and/or industry create a benchmark piece of software/hardware to be used by all manufacturers (likely 1-3 years from now)Should take less than 5 minutes to complete the test on a single vehicleVerification of MonitorsRequired on one vehicle per DDV test group (total of 1-3 per manufacturer)Requires every single monitor to be exercised with a fault present and verify fault code is setRequired to be completed within 120 days after production startsEstimates for test time range from 2-5 weeks per car.Collection of In-use data Requires manufacturers to collect data from a small sample of actual in-use vehicles in the first six monthsData required to be collected for every test group (but number of vehicles per test group could be as few as 20-30) In-use Monitoring ConditionsCurrently, manufacturers required to seek CARB approval of the monitoring conditionsConditions must ensure robust monitoring, occur frequently in-use (real world), and generally, occur on the FTP or Unified cycleManufacturers requested this flexibility to determine the conditions case-by-case when the regulation was originally adoptedIn-use Monitoring Conditions (cont.)With this flexibility, the vast majority of manufacturers have developed monitoring conditions that achieve all three requirementsOthers, however, have asked for increased clarity regarding in-use performanceStill others have felt performance on the FTP alone should be good enoughIn-use Monitoring Conditions (cont.)This demand for a more precise in-use performance standard has led to CARB consideration of two concepts:Standardized monitoring conditionsRate-based monitoring conditionsStandardized Monitoring ConditionsCARB would define the precise monitoring conditions for monitorsWould ensure consistent performance by all manufacturers, simplify approval process, and likely provide adequate in-use performanceWould require major redesign by most manufacturers and put burden of in-use performance on CARB staffStandardized Monitoring Conditions (cont.)Most significantly, this concept does not allow manufacturers much room to optimize or tweak monitors for each make/model.Development of this concept essentially halted because of inherent problems with creating common conditions across all manufacturers.Rate-based Monitoring ConditionsManufacturers would continue to select monitoring conditions but each vehicle would contain counters to track monitoring frequency in-useManufacturers would be held liable for maintaining a minimum in-use frequencyWould answer the bottom line question- How often does this monitor run?Rate-based Monitoring Conditions (cont.)Appears to be the best compromise between providing flexibility to manufacturers to optimize conditions and maintaining consistent and adequate in-use performanceEnsures all manufacturers held to the same performance standardProvides an objective evaluation criteria to be used by ARB and industryRate-based ProposalVehicles will keep track of numerators and denominators for catalyst, evap, O2, EGR, and secondary airNumerator will keep track of how many times a particular monitor has runDenominator will keep track of how many times a vehicle has been operatedRatio of the two will indicate how often monitor is running.Numerator ProposalNumerator would increment by one each time the monitor met all the conditions necessary to detect a malfunctionDenominator ProposalDenominator would increment by one each time the vehicle met certain generic drive cycle conditionsTrip > 10 minutesElevation < 8000 feetAmbient temp > 20 FVehicle operation above 25 mph for > 5 minutes At least one idle of > 30 secondsDenominator Proposal (cont.)Secondary air monitor denominator would also add:Secondary air commanded on for >10 secsEvap leak check monitor denominator would instead add:40 F < Ambient temp < 95 F for 10 minutesCold start defined as: 40 F < ECT at start-up < 95 F and (ECT at start-up - IAT at start-up) < 12 FIn-use Monitoring Performance GoalsDesign target is a MIL in two weeks for 90% of the in-use vehiclesStaffs best estimate at this time is that a ratio (Numerator/Denominator) of > 0.25 would equate to a MIL in two weeks for 90% of the vehiclesIn-use Monitoring PerformanceOriginal ProposalProposal required 50/75/100% phase-in of numerators/denominators in 2005/06/07 with a design goal of 0.25 for the ratioProposal also required recall if ratio was In-use Monitoring PerformanceRevised ProposalProposal requires 100% phase-in of numerators/denominators in 2005 with a design goal of 0.25 for the ratioProposal would eliminate recall for ratios >0.1 for 2005 and 2006 and make recalls possible (not mandatory) for ratios from 0.0 to 0.1From 2007 on, mandatory recall for ratios < 0.1 and possible for ratios between 0.1 and 0.25In-use Monitoring PerformanceObviously, proposal will likely require revisions to fine-tune the required ratio as data is collected in the first few yearsRatios may need to increased or decreased to better correlate with the design goal of MIL illumination in two weeks for 90% of the vehiclesFor instance, 0.25 for secondary air and evap monitor denominators is very likely too low and will need to be increasedIn-use Monitoring Performance

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