Document ID: chunk:federal_register_of_legislation:F2023L00129:reg:10:p48
Version: federal_register_of_legislation:F2023L00129
Segment Type: reg
Provision Reference: reg 10 (pt 48/150)
Character Range: 848089–850971

the applicable activation mode, as described in the following paragraphs; or the absence of a malfunction by a series of single flashes. When applicable, each flash consists of a 1s MI-on followed by a one second MI-off, and the series of flashes will be followed by a period of four seconds with the MI off.
 Four activation modes are considered, where activation mode 4 shall take precedence over activation modes 1, 2 and 3, activation mode 3 shall take precedence over activation modes 1 and 2, and activation mode 2 shall take precedence over activation mode 1.
4.6.4.2.1. Activation mode 1 - absence of malfunction
 The MI shall blink for one flash.
4.6.4.2.2. Activation mode 2 - "On-demand-MI"
 The MI shall show blink for two flashes if the OBD system would command an on-demand-MI according to the discriminatory display strategy described in paragraph 4.6.3.1.
4.6.4.2.3. Activation mode 3 - "short-MI"
 The MI shall blink for three flashes if the OBD system would command a short-MI according to the discriminatory display strategy described in paragraph 4.6.3.1.
4.6.4.2.4. Activation mode 4 - "continuous-MI"
 The MI shall remain continuously ON ("continuous-MI") if the OBD system would command a continuous-MI according to the discriminatory display strategy described in paragraph 4.6.3.1.
4.6.5. Counters associated with malfunctions
4.6.5.1. MI counters
4.6.5.1.1. Continuous-MI Counter
 The OBD system shall contain a continuous-MI counter to record the number of hours during which the internal combustion engine has been operated while a continuous-MI is activated.
 The continuous-MI counter shall count up to the maximum value provided in a 2 byte counter with 1 hour resolution and hold that value unless the conditions allowing the counter to be reset to zero are met.
 The continuous-MI counter shall operate as follows:
(a) If starting from zero, the continuous-MI counter shall begin counting as soon as a continuous-MI is activated;
(b) The continuous-MI counter shall halt and hold its present value when the continuous-MI is no longer activated;
(c) The continuous-MI counter shall continue counting from the point at which it had been held if a malfunction that results in a continuous-MI is detected within 3 operating sequences;
(d) The continuous-MI counter shall start again counting from zero when a malfunction that results in a continuous-MI is detected after 3 operating sequences since the counter was last held;
(e) The continuous-MI counter shall be reset to zero when:
(i) No malfunction that results in a continuous-MI is detected during 40 warm-up cycles or 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