Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:10:p54
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 10 (pt 54/150)
Character Range: 863846–866669

OBD system shall report the most accurate values that are calculated within the applicable electronic control unit (e.g. the engine control computer).
 Table 1 in Appendix 5 to this annex gives the list of mandatory OBD information relating to the engine load and speed.
 Table 3 in Appendix 5 to this annex shows the other OBD information which must be included if used by the emission or OBD system to enable or disable any OBD monitors.
 Table 4 in Appendix 5 to this annex shows the information which is required to be included if the engine is so equipped, senses or calculates the information[37]. At the decision of the manufacturer, other freeze frame or data stream information may be included.
 In case a device is monitored by the OBD system and is not covered by Appendix 5 to this annex (e.g. SCR), the data-stream information shall include elements of information for the sensors and actuators of this device in a way similar to those described in Appendix 5 to this annex. This shall be submitted for approval by the Type Approval Authority at the time of approval.
4.7.3. Access to OBD information
 Access to OBD information shall be provided only in accordance with the standards mentioned in Appendix 6 to this annex and the following sub-paragraphs[38].
 Access to the OBD information shall not be dependent on any access code or other device or method obtainable only from the manufacturer or its suppliers. Interpretation of the OBD information shall not require any unique decoding information, unless that information is publicly available.
 A single access method (e.g. a single access point/node) to OBD information shall be supported to retrieve all OBD information. This method shall permit access to the complete OBD information required by this annex. This method shall also permit access to specific smaller information packages as defined in this annex (e.g. road worthiness information packages in case of emission related OBD).
 Access to OBD information shall be provided using at least one of the following series of standards mentioned in Appendix 6 to this annex:
(a) ISO 27145 with ISO 15765-4 (CAN-based);
(b) ISO 27145 with ISO 13400 (TCP/IP-based);
(c) SAE J1939-73.
               Manufacturers shall use appropriate ISO or SAE-defined fault codes (for example, P0xxx, P2xxx, etc.) whenever possible. If such identification is not possible, the manufacturer may use diagnostic trouble codes according to the relevant clauses in ISO 27145 or SAE J1939. The fault codes must be fully accessible by standardized diagnostic equipment complying with the provisions of this annex.
               The manufacturer shall provide the ISO or SAE standardization body through the appropriate ISO or SAE process with emission-related diagnostic data not specified by ISO 27145 or SAE J1939 but