Commission Delegated Regulation (EU) 2015/68Show full title

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

4.1. Tractors

4.1.1. With the parking braking system 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. In the case of tractors authorised to tow vehicles of category R3b or R4b, such vehicles shall provide a full control signal for the service braking system of the towed vehicle. It should be understood that sufficient energy is available in the energy transmission of the service braking system.

4.1.2. 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.

4.1.3. A failure within the electric control transmission, not including its energy reserve, that affects the function and performance of systems addressed in this Regulation shall be indicated to the driver by the red or yellow warning signal specified in points 2.2.1.29.1.1 and 2.2.1.29.1.2 of Annex I, respectively, as appropriate. When the prescribed service braking performance can no longer be achieved (warning signal), failures resulting from a loss of electrical continuity (e.g. breakage, disconnection) shall be signalled to the driver as soon as they occur, and the prescribed residual braking performance shall be fulfilled by operating the service braking control in accordance with point 3.1.4 of Annex II.

The manufacturer shall provide the Technical Service with an analysis of potential failures within the control transmission and their effects. This information shall be subject to discussion and agreement between the Technical Service and the vehicle manufacturer.

These requirements shall not be construed as a departure from the requirements concerning secondary braking.

4.1.4. A tractor electrically connected to a towed vehicle via an electric control line, shall provide a clear warning to the driver whenever the towed vehicle provides the failure information that the stored energy in any part of the service braking system on the towed vehicle falls below the warning level, as specified in point 5.2.4. A similar warning shall also be provided when a continuous failure (> 40 ms) within the electric control transmission of the towed vehicle, excluding its energy reserve, precludes achievement of the prescribed service braking performance of the towed vehicle, as specified in point 4.2.3. The warning signal specified in point 2.2.1.29.2.1 of Annex I shall be used for this purpose.

4.1.5. In the event of a failure of the energy source of the electric control transmission, starting from the nominal value of the energy level, the full control range of the service braking system shall be guaranteed after twenty consecutive full stroke actuations of the service braking control device. During the test, the braking control device shall be fully applied for 20 seconds and released for 5 seconds on each actuation. It should be understood that during the above test, sufficient energy is available in the energy transmission to ensure full actuation of the service braking system. This requirement shall not be construed as a departure from the requirements of Annex IV.

4.1.6. When the battery voltage falls below a value nominated by the manufacturer at which the prescribed service braking performance can no longer be guaranteed and/or which precludes at least two independent service braking circuits from each achieving the prescribed secondary or residual braking performance, the warning signal specified in point 2.2.1.29.1.1 of Annex I shall be activated. After the warning signal has been activated, it shall be possible to apply the service braking control device and obtain at least the performances prescribed for residual and secondary braking in the case of tractor with maximum design speed exceeding 60 km/h or the performance prescribed for secondary braking in the case of tractor with maximum design speed not exceeding 60 km/h. It should be understood that sufficient energy is available in the energy transmission of the service braking system. This requirement shall not be construed as a departure from the requirement concerning secondary braking.

4.1.7. If auxiliary equipment is supplied with energy from the same reserve as the electric control transmission, it shall be ensured that, with the engine running at a speed not greater than 80 % of the maximum power speed, the supply of energy is sufficient to fulfil the prescribed deceleration values by either provision of an energy supply which is able to prevent discharge of this reserve when all auxiliary equipment is functioning or by automatically switching off pre-selected parts of the auxiliary equipment at a voltage above the critical level referred to in point 4.1.6 such that further discharge of this reserve is prevented. Compliance may be demonstrated by calculation or by a practical test. For vehicles authorised to tow a vehicle of category R3b or R4b the energy consumption of the towed vehicle shall be taken into account by a load of 400 W. This point does not apply to vehicles where the prescribed deceleration values can be reached without the use of electrical energy.

4.1.8. If the auxiliary equipment is supplied with energy from the electric control transmission, the following requirements shall be fulfilled.

4.1.8.1. In the event of a failure in the energy source, whilst the vehicle is in motion, the energy in the reservoir shall be sufficient to actuate the brakes when the control device is applied.

4.1.8.2. In the event of a failure in the energy source, whilst the vehicle is stationary and the parking braking system applied, the energy in the reservoir shall be sufficient to actuate the lights even when the brakes are applied.

4.1.9. In the case of a failure in the electric control transmission of the service braking system of a tractor equipped with an electric control line according to point 2.1.4.1.2 or 2.1.4.1.3 of Annex I, the full actuation of the brakes of the towed vehicle shall remain ensured.

4.1.10. In the case of a failure in the electric control transmission of a towed vehicle, electrically connected via an electric control line only, according to point 2.1.4.1.3 of Annex I, braking of the towed vehicle shall be ensured according to point 2.2.1.17.3.1 of Annex I. This shall be the case whenever the towed vehicle provides the ‘supply line braking request’ signal via the data communication part of the electric control line or in the event of the continuous absence of this data communication. This point shall not apply to tractors which cannot be operated with towed vehicles connected via an electric control line only, as described in point 3.4.

4.2. Trailers

4.2.1. 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.

4.2.2. In the case of a failure within the electric control transmission (e.g. breakage, disconnection), of at least 30 % of the prescribed performance for the service braking system of the relevant towed vehicle shall be maintained.

Until uniform test procedures have been agreed, the manufacturer shall provide the Technical Service with an analysis of potential failures within the control transmission, and their effects. This information shall be subject to discussion and agreement between the Technical Service and the vehicle manufacturer.

For towed vehicles, electrically connected via an electric control line only, according to point 2.1.4.1.3 of Annex I, and fulfilling 2.2.1.17.3.2 of Annex I with the performance prescribed in point 3.2.3 of Annex II, it is sufficient that the provisions of point 4.1.10 are invoked, when a braking performance of at least 30 % of the prescribed performance for the service braking system of the towed vehicle can no longer be ensured, by either providing the ‘supply line braking request’ signal via the data communication part of the electric control line or by the continuous absence of this data communication.

4.2.3. A failure within the electric control transmission of the towed vehicle that affects the function and performance of systems addressed by this Regulation and failures of energy supply available from the ISO 7638:2003 connector shall be indicated to the driver by the separate warning signal specified in point 2.2.1.29.2 of Annex I via pin 5 of the electrical connector conforming to ISO 7638:2003. In addition, towed vehicles equipped with an electric control line, when electrically connected to a tractor with an electric control line, shall provide the failure information for activation of the warning signal specified in point 2.2.1.29.2.1 of Annex I via the data communication part of the electric control line, when the prescribed service braking performance of the towed vehicle can no longer be ensured.

However, in the case of any failure of the energy supply available from the ISO 7638:2003 connector, the indication of the yellow warning signal via pin 5 of the electrical connector conforming to ISO 7638:2003 is sufficient under the condition that the full braking force is still available.