Document ID: chunk:federal_register_of_legislation:F2021C00476:body:0:p21
Version: federal_register_of_legislation:F2021C00476
Segment Type: other
Provision Reference: 
Character Range: 57133–60122

transmission (park position) may be used to achieve or assist in achieving the above performance.

         5.2.19.2.1. A break in the wiring within the electrical transmission, or an electrical failure in the control of the parking braking system shall be signalled to the driver by the yellow warning signal specified in paragraph 5.2.21.1.2.  When caused by a break in the wiring within the electrical control transmission of the parking braking system, this yellow warning signal shall be signalled as soon as the break occurs.

          In addition, such an electrical failure in the control or break in the wiring external to the electronic control unit(s) and excluding the energy supply shall be signalled to the driver by flashing the red warning signal specified in paragraph 5.2.21.1.1. as long as the ignition (start) switch is in the "on" (run) position including a period of not less than 10 seconds thereafter and the control is in the "on" (activated) position.

         However, if the parking braking system detects correct clamping of the parking brake, the flashing of the red warning signal may be suppressed and the non-flashing red signal shall be used to indicate "parking brake applied.

         Where actuation of the parking brake is normally indicated by a separate red warning signal, satisfying all the requirements of paragraph 5.2.21.2., this signal shall be used to satisfy the above requirement for a red signal.

         5.2.19.3. Auxiliary equipment may be supplied with energy from the electric transmission of the parking braking system provided that the supply of energy is sufficient to allow the actuation of the parking braking system in addition to the vehicle electrical load under non-fault conditions.  In addition, where the energy reserve is also used by the service braking system, the requirements of paragraph 5.2.20.6. shall apply.

         5.2.19.4. After the ignition/start switch which controls the electrical energy for the braking equipment has been switched off and/or the key removed, it shall remain possible to apply the parking braking system, whereas releasing shall be prevented.

         5.2.20. Special additional requirements for service braking systems with electric control transmission:

         5.2.20.1. With the parking brake released, the service braking system shall be able to generate a static total braking force at least equivalent to that required by the prescribed Type-0 test, even when the ignition/start switch has been switched off and/or the key has been removed.  It should be understood that sufficient energy is available in the energy transmission of the service braking system.

         5.2.20.2. In the case of a single temporary failure ( 40 ms) within the electric control transmission, excluding its energy supply, (e.g. non-transmitted signal or data error) there shall be no distinguishable effect on the service braking performance.

         5.2.20.3. A failure within the electric