Document ID: chunk:federal_register_of_legislation:F2024L00446:reg:16:p78
Version: federal_register_of_legislation:F2024L00446
Segment Type: reg
Provision Reference: reg 16 (pt 78/108)
Character Range: 1108427–1111418

4WD operation which fulfils the specifications in paragraphs 2.2. and 2.3. of Annex B5.

              2.4.2.4.2. If the test vehicle is tested with only one powered axle, the test vehicle shall be tested on a dynamometer in 2WD operation which fulfils the specifications in paragraph 2.2. of Annex B5.

              At the request of the manufacturer and with the approval of the approval authority a vehicle with one powered axle may be tested on a 4WD dynamometer in 4WD operation mode.

              2.4.2.4.3. If the test vehicle is operated with two axles being powered in dedicated driver-selectable modes which are not intended for normal daily operation but only for special limited purposes, such as 'mountain mode' or 'maintenance mode', or when the mode with two powered axles is only activated in an off-road situation, the vehicle shall be tested on a dynamometer in 2WD operation which fulfils the specifications in paragraph 2.2. of Annex B5.

              At the request of the manufacturer and with the approval of the approval authority, the vehicle may be tested on a 4WD dynamometer in 4WD operation mode.

              2.4.2.4.4. If the test vehicle is tested on a 4WD dynamometer in 2WD operation the wheels on the non-powered axle may rotate during the test, provided that the vehicle dynamometer operation mode and vehicle coastdown mode support this way of operation.

              Figure A6/5a
              Possible test configurations on 2WD and 4WD dynamometers

              2.4.2.5. Demonstration of equivalency between a dynamometer in 2WD operation and a dynamometer in 4WD operation

              2.4.2.5.1. At the request of the manufacturer and with the approval of the approval authority, the vehicle which has to be tested on a dynamometer in 4WD operation may alternatively be tested on a dynamometer in 2WD operation if the following conditions are met:

                  (a) The test vehicle is converted to have only one powered axle;

                  (b) The manufacturer demonstrates to the approval authority that the CO2, fuel consumption and/or electrical energy consumption of the converted vehicle is the same or higher as for the non-converted vehicle being tested on a dynamometer in 4WD operation;

                  (c) A safe operation is ensured for the test (e.g. by removing a fuse or dismounting a drive shaft) and an instruction is provided together with the dynamometer operation mode;

                  (d) The conversion is only applied to the vehicle tested at the chassis dynamometer, the road load determination procedure shall be applied to the unconverted test vehicle.

              2.4.2.5.2. This demonstration of equivalency shall apply to all vehicles in the same road load family. At the request of the manufacturer, and with approval of the approval authority, this demonstration of equivalency may be extended to other road load families upon evidence that a vehicle from the worst-case road load family