Document ID: chunk:federal_register_of_legislation:F2025C00108:reg:4:p8
Version: federal_register_of_legislation:F2025C00108
Segment Type: reg
Provision Reference: reg 4 (pt 8/25)
Character Range: 107505–110717

means for an operator to manually disable a mandatory 'Vehicle Stability Function', the 'Vehicle Stability Function' must be automatically reinstated no later than when the vehicle reaches a speed of 40 km/h and at the initiation of each new ignition cycle.
     4.                            When a vehicle is equipped with a means to automatically disable a mandatory 'Vehicle Stability Function', to provide increased traction by modifying the functionality of the drive train, the disablement and its re-instatement must be automatically linked to the operation which changes the functionality of the drive train.
     5.                            In the cases permitted by clauses 2.3 and 2.4 of this appendix above, a constant yellow optical warning signal must inform the driver that the 'Vehicle Stability Function' has been disabled.  The yellow warning signal specified in paragraph 3 of this appendix below may be used for this purpose.  The warning signal must be distinct and separate from any 'Service Brake System' failure 'Visible Indicator' lamp provided pursuant to clause 5.2 of this standard.

 1.                                  Intervention and failure warning signals
     1.                            The tell-tale for the following intervention and failure signals must be identified by the text "ESC" or the symbol shown in Diagram 1 for "Vehicle Stability Function Intervention/Failure Tell-tale".  This tell-tale must be indicated as active either when constantly illuminated or flashing as indicated below.  The illumination must be yellow.
         1.                     The signal must be visible to the driver, even in daylight, such that the driver can easily verify the satisfactory condition of the signal without leaving the driver's seat.  It must be located in the same region set out in clause 5.2.12 of this standard.
     2.                            Interventions of the 'Vehicle Stability Function' must be indicated to the driver by a flashing optical warning signal fulfilling the requirements of clause 3.1 of this appendix.  The indication must be present as long as the 'Vehicle Stability Function' is in an intervention mode.
         1.                     Additionally, interventions by systems related to the 'Vehicle Stability Function' (including traction control, trailer stability assist, corner brake control, and other similar functions that use throttle and/or individual torque control to operate and share common components with vehicle stability function) may also be indicated to the driver by this flashing optical warning signal.
         2.                     Interventions of the 'Vehicle Stability Function' used in any learning process to determine the vehicle operational characteristics must not generate the above signal.
     3.                            A 'Vehicle Stability Function' failure or defect must be detected and indicated to the driver by an optical warning signal fulfilling the requirements of clause 3.1 of this appendix.
         1.                     The warning signal must be constant and remain displayed as long as the failure or defect persists and the ignition (start) switch is in the 'on' (run) position.