Document ID: chunk:federal_register_of_legislation:F2024L00446:reg:13:p11
Version: federal_register_of_legislation:F2024L00446
Segment Type: reg
Provision Reference: reg 13 (pt 11/23)
Character Range: 1973118–1976194

The procedure describes a method for checking the function of the On-Board Diagnostic (OBD) system installed on the vehicle by failure simulation of relevant systems in the engine management or emission control system. It also sets procedures for determining the durability of OBD systems.

              The manufacturer shall make available the defective components and/or electrical devices which would be used to simulate failures. When measured over the Type 1 test cycle, such defective components or devices shall not cause the vehicle emissions to exceed any of the OBD thresholds set out in Table 4A and Table 4B (as applicable) in paragraph 6.8.2. of this Regulation by more than 20 per cent. For electrical failures (short/open circuit), the emissions may exceed these OBD thresholds by more than twenty per cent.

              When the vehicle is tested with the defective component or device fitted, the OBD system is approved if the MI is activated. The OBD system is also approved if the MI is activated below the OBD thresholds.

              2. Description of test

              2.1. The testing of OBD systems consists of the following phases:

              2.1.1. Simulation of malfunction of a component of the engine management or emission control system;

              2.1.2. Preconditioning of the vehicle with a simulated malfunction over preconditioning specified in paragraph 6.2.1. or paragraph 6.2.2. of this appendix;

              2.1.3. Driving the vehicle with a simulated malfunction over the Type 1 test cycle and measuring the emissions of the vehicle. When driving the vehicle with a simulated malfunction, the drive trace indices and tolerances set out in paragraph 2.6.8.3.2. of Annex B6 shall not apply;

              2.1.4. Determining whether the OBD system reacts to the simulated malfunction and indicates malfunction in an appropriate manner to the vehicle driver.

              2.2. Alternatively, at the request of the manufacturer, malfunction of one or more components may be electronically simulated according to the requirements of paragraph 6. of this appendix.

              2.3. Manufacturers may request that monitoring take place outside the Type 1 test cycle if it can be demonstrated to the Type Approval Authority that monitoring during conditions encountered during the Type 1 test cycle would impose restrictive monitoring conditions when the vehicle is used in service.

              2.4. For OVC-HEVs, testing shall be carried out under charge-sustaining conditions.

              3. Test vehicle and fuel

              3.1. Vehicle

               The test vehicle shall meet the requirements of paragraph 2.3. of Annex B6 to this Regulation.

              3.2. Fuel

               The appropriate reference fuel as described in Annex B3 to this Regulation shall be used for testing. The fuel type for each failure mode to be tested (described in paragraph 6.3. of this appendix) may be selected by the Type Approval Authority from the reference fuels described in Annex B3 to this Regulation in the