Document ID: chunk:federal_register_of_legislation:F2021C00477:body:0:p61
Version: federal_register_of_legislation:F2021C00477
Segment Type: other
Provision Reference: 
Character Range: 160266–163203

terms, how the system will behave on the occurrence of any one of those specified faults which will have a bearing on vehicle control performance or safety.
 This may be based on a Failure Mode and Effect Analysis (FMEA), a Fault Tree Analysis (FTA) or any similar process appropriate to system safety considerations.
 The chosen analytical approach(es) shall be established and maintained by the manufacturer and shall be made open for inspection by the technical service at the time of the type approval.

3.4.4.1. This documentation shall itemise the parameters being monitored and shall set out, for each fault condition of the type defined in paragraph 3.4.4. above, the warning signal to be given to the driver and/or to service/technical inspection personnel.
4. Verification and test
4.1. The functional operation of "The System", as laid out in the documents required in paragraph 3., shall be tested as follows:
4.1.1. Verification of the function of "The System"
 As the means of establishing the normal operational levels, verification of the performance of the vehicle system under non-fault conditions shall be conducted against the manufacturer's basic benchmark specification unless this is subject to a specified performance test as part of the approval procedure of this or another Regulation.
4.1.2. Verification of the safety concept of paragraph 3.4.
 The reaction of "The System" shall, at the discretion of the type approval authority, be checked under the influence of a failure in any individual unit by applying corresponding output signals to electrical units or mechanical elements in order to simulate the effects of internal faults within the unit.
 The verification results shall correspond with the documented summary of the failure analysis, to a level of overall effect such that the safety concept and execution are confirmed as being adequate.

Annex 9

Electronic stability control and brake assist systems
A. Requirements for electronic stability control systems, where fitted
1. General requirements
 Vehicles equipped with an ESC system shall meet the functional requirements specified in paragraph 2. and the performance requirements in paragraph 3. under the test procedures specified in paragraph 4. and under the test conditions specified in paragraph 5. of this section.
2. Functional requirements
 Each vehicle to which this annex applies shall be equipped with an electronic stability control system that:
2.1. Is capable of applying braking torques individually to all four wheels[31] and has a control algorithm that utilizes this capability;
2.2. Is operational over the full speed range of the vehicle, during all phases of driving including acceleration, coasting, and deceleration (including braking), except:
2.2.1. When the driver has disabled ESC;
2.2.2. When the vehicle speed is below 20 km/h;
2.2.3. While the initial start-up self test and plausibility checks are completed,