Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:10:p49
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 10 (pt 49/150)
Character Range: 850694–853537

200 engine operating hours since the counter was last held whichever occurs first; or
(ii) The OBD scan tool commands the OBD System to clear OBD information.
       Figure C1
       Illustration of the MI counters activation principles

       Figure C2
       Illustration of the B1 counter activation principles

       4.6.5.1.2. Cumulative continuous-MI counter
 The OBD system shall contain a cumulative continuous-MI counter to record the cumulative number of hours during which the internal combustion engine has been operated over its life while a continuous-MI is activated.
 The cumulative continuous-MI counter shall count up to the maximum value provided in a 2-byte counter with 1 hour resolution and hold that value.
 The cumulative continuous-MI counter shall not be reset to zero by the engine system, a scan tool or a disconnection of a battery.
 The cumulative continuous-MI counter shall operate as follows:
(a) The cumulative continuous-MI counter shall begin counting when the continuous-MI is activated;
(b) The cumulative continuous-MI counter shall halt and hold its present value when the continuous-MI is no longer activated;
(c) The cumulative continuous-MI counter shall continue counting from the point it had been held when a continuous-MI is activated.
 Figure C1 illustrates the principle of the cumulative continuous-MI counter and Appendix 2 to this annex contains examples that illustrate the logic.
       4.6.5.2. Counters associated with Class B1 malfunctions
4.6.5.2.1. Single B1-counter
 The OBD system shall contain a B1 counter to record the number of hours during which the internal combustion engine has operated while a Class B1 malfunction is present.
 The B1 counter shall operate as follows:
(a) The B1 counter shall begin counting as soon as a Class B1 malfunction is detected and a confirmed and active DTC has been stored;
(b) The B1 counter shall halt and hold its present value if no Class B1 malfunction is confirmed and active, or when all Class B1 malfunction have been erased by a scan tool;
(c) The B1 counter shall continue counting from the point it had been held if a subsequent Class B1 malfunction is detected within 3 operating sequences.
 In the case where the B1 counter has exceeded 200 engine running hours, the OBD system shall set the counter to 190 engine running hours when the OBD system has determined that a Class B1 malfunction is no longer confirmed and active, or when all Class B1 malfunctions have been erased by a scan tool. The B1 counter shall begin counting from 190 engine running hours if a subsequent Class B1 malfunction is present within 3 operating sequences.
 The B1 counter shall be reset to zero when three consecutive operating sequences have occurred during which no Class B1 malfunctions have been detected.
Note: The B1 counter does not indicate