Document ID: chunk:federal_register_of_legislation:F2008C00323:reg:11:p12
Version: federal_register_of_legislation:F2008C00323
Segment Type: reg
Provision Reference: reg 11 (pt 12/45)
Character Range: 453521–456537

and shall notify the approval authority accordingly.

         In the event of failure to comply with these provisions the approval authority shall act to ensure that repair information is available, in accordance with the procedures laid down for type approval and in-service surveys.

         3.2. The OBD system shall be so designed, constructed and installed in a vehicle as to enable it to comply with the requirements of this annex during conditions of normal use.

         3.2.1. Temporary disablement of the OBD system

         3.2.1.1.  A manufacturer may disable the OBD system if its ability to monitor is affected by low fuel levels. Disablement shall not occur when the fuel tank level is above 20 per cent of the nominal capacity of the fuel tank.

         3.2.1.2.  A manufacturer may disable the OBD system at ambient engine starting temperatures below 266 K (–7 C) or at elevations over 2,500 metres above sea level provided the manufacturer submits data and/or an engineering evaluation which adequately demonstrate that monitoring would be unreliable when such conditions exist. A manufacturer may also request disablement of the OBD system at other ambient engine starting temperatures if he demonstrates to the authority with data and/or an engineering evaluation that misdiagnosis would occur under such conditions. It is not necessary to illuminate the malfunction indicator (MI) if the OBD thresholds are exceeded during a regeneration provided no defect is present.

         3.2.1.3.  For vehicles designed to accommodate the installation of power take-off units, disablement of affected monitoring systems is permitted provided disablement occurs only when the power take-off unit is active.

         3.2.2. Engine misfire in vehicles equipped with positive-ignition engines

         3.2.2.1. Manufacturers may adopt higher misfire percentage malfunction criteria than those declared to the authority, under specific engine speed and load conditions where it can be demonstrated to the authority that the detection of lower levels of misfire would be unreliable.

         3.2.2.2. When a manufacturer can demonstrate to the authority that the detection of higher levels of misfire percentages is still not feasible, or that misfire cannot be distinguished from other effects (e.g. rough roads, transmission shifts, after engine starting; etc.) the misfire monitoring system may be disabled when such conditions exist.

         3.3. Description of tests

         3.3.1. The test are carried out on the vehicle used for the Type V durability test, given in Annex 9, and using the test procedure in Appendix 1 to this annex. Tests are carried out at the conclusion of the Type V durability testing.

         When no Type V durability testing is carried out, or at the request of the manufacturer, a suitably aged and representative vehicle may be used for these OBD demonstration tests.

         3.3.2. The OBD system shall indicate the failure of an emission-related component or