ISO 7635:2006

INTERNATIONAL ISO
STANDARD 7635
Third edition
2006-06-01
Road vehicles — Air and air/hydraulic
braking systems of motor vehicles,
including those with electronic control
functions — Test procedures
Véhicules routiers — Systèmes de freinage à air comprimé ou
hydropneumatiques pour les véhicules à moteur, y compris les
systèmes à fonctions de commande électroniques — Méthodes d'essai

Reference number
©
ISO 2006
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©  ISO 2006
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ii © ISO 2006 – All rights reserved

Contents Page
Foreword. v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 Symbols . 4
5 Test site conditions . 6
5.1 Test site . 6
5.2 Road surface condition. 6
5.3 Ambient conditions . 7
6 General requirements. 7
7 Recommended sequence of the tests . 8
7.1 Preparation and static checks and tests. 8
7.2 Basic performance tests — Unladen . 9
7.3 Failure tests – Unladen. 9
7.4 ABS tests — Unladen . 9
7.5 ABS tests — Laden. 10
7.6 Failure tests — Laden. 10
7.7 Basic performance tests — Laden. 10
8 Vehicle preparation. 11
8.1 Documents and basic data . 11
8.2 Braking system condition and bedding . 11
8.3 Adjustment of braking equipment . 11
8.4 Tyre conditions . 11
8.5 Devices and instruments needed for the testing . 11
9 Static tests and checks . 13
9.1 Static braking force and control force vs. line pressure . 13
9.2 Capacity of energy sources. 13
9.3 Service braking system — Response time measurement. 14
9.4 Automatic braking . 15
9.5 Brake failure and defect warning signals. 15
9.6 Tests on vehicles equipped with spring brake actuators. 17
9.7 Additional tests on vehicles equipped with EBS . 18
10 Basic performance tests — Unladen . 18
10.1 Type 0 test (service braking system cold brake effectiveness, engine disconnected). 18
10.2 Type 0 test (service braking system cold brake, engine connected). 19
10.3 Parking braking system — Hill holding test . 19
10.4 Secondary braking system test. 19
10.5 Wheel locking sequence . 20
11 Failure tests — Unladen. 20
11.1 Service braking system partial failure test (type 0 test, cold brake effectiveness, engine
disconnected). 20
11.2 Failed load sensing device test/function test . 21
11.3 Failure of the energy source on vehicles equipped with EBS . 21
12 ABS tests — Unladen . 22
12.1 ABS failure. 22
12.2 Determination of the peak coefficient of adhesion on the high adhesion surface. 23
12.3 Determination of adhesion utilization on high adhesion surface. 24
12.4 Determination of adhesion utilization on low adhesion surface. 26
12.5 Additional checks . 26
13 ABS tests — Laden . 27
13.1 Additional split adhesion test. 27
13.2 Energy consumption on low adhesion surface . 27
14 Failure tests — Laden. 30
14.1 Service braking system partial failure test (type 0 test, cold brake effectiveness, engine
disconnected). 30
14.2 Failed load sensing device test . 30
14.3 Energy source failure test. 30
15 Basic performance tests — Laden . 30
15.1 Parking braking system — Hill holding test. 30
15.2 Parking braking system — Dynamic test . 32
15.3 Wheel locking sequence . 32
15.4 Type 0 test (service braking system cold brake effectiveness, engine disconnected). 32
15.5 Type 0 test (service braking system cold brake, engine connected) . 32
15.6 Warning device test . 33
15.7 Energy storage capacity test . 33
15.8 Type II or type IIA tests (downhill, endurance braking test). 33
15.9 Type I test (fade test) . 36
Annex A (normative) Typical braking equipment. 38
Bibliography . 40

iv © ISO 2006 – All rights reserved

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 7635 was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 2, Braking
systems and equipment.
This third edition cancels and replaces the second edition (ISO 7635:2003), which has been technically
revised.
INTERNATIONAL STANDARD ISO 7635:2006(E)

Road vehicles — Air and air/hydraulic braking systems of motor
vehicles, including those with electronic control functions —
Test procedures
1 Scope
This International Standard specifies the method of testing the air or air over hydraulic braking systems of
vehicles of categories M and N (excluding M1 and N1) as defined in Annex 7 to the UN-ECE Consolidated
Resolution on the Construction of Vehicles (R.E.3.) which are built to comply with UN-ECE Regulation 13/09
including supplements 1-6. Test methods covering lock actuators or the electrical regenerative braking
systems of electric and hybrid vehicles are not included in this edition.
NOTE Requirements of UN-ECE Regulation 13 related purely to the design of braking systems and braking system
components are not part of this International Standard.
The values in square brackets [ ] and the values in tables are taken from UN-ECE Regulation No. 13.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 611:2003, Road vehicles — Braking of automotive vehicles and their trailers — Vocabulary
ISO 1176:1990, Road vehicles — Masses — Vocabulary and codes
ISO 3833:1977, Road vehicles — Types — Terms and definitions
ISO 7638-1, Road vehicles — Connectors for the electrical connection of towing and towed vehicles — Part 1:
Connectors for braking systems and running gear of vehicles with 24 V nominal supply voltage
ISO 7638-2, Road vehicles — Connectors for the electrical connection of towing and towed vehicles — Part 2:
Connectors for braking systems and running gear of vehicles with 12 V nominal supply voltage
ISO 11992 (all parts), Road vehicles — Interchange of digital information on electrical connections between
towing and towed vehicles
ISO 12161, Road vehicles — Endurance braking systems of motor vehicles and towed vehicles — Test
procedures
ISO 21069-1:2004, Road vehicles — Test of braking systems on vehicles with a maximum authorized total
mass of over 3,5 t using a roller brake tester — Part 1: Pneumatic braking systems
1)
ISO 21069-2 , Road vehicles — Test of braking systems on vehicles with a maximum authorized total mass
of over 3,5 t using a roller brake tester — Part 2: Air over hydraulic braking systems
UN-ECE Regulation N° 13, Uniform provisions concerning the approval of vehicles with regard to braking
NOTE UN-ECE Regulation 13 is periodically updated through amendments and supplements, with this International
Standard having been prepared in accordance with the 09 series of amendments including supplements 1 to 6. When
using this International Standard, care should be taken to ensure that changes have not subsequently occurred that affect
the test methods or values given.
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 611, ISO 1176, and ISO 3833 and
the following apply.
3.1
braking systems
3.1.1
air-over hydraulic braking system
braking system having stored pneumatic energy, hydraulically actuated brakes and transmission means
incorporating a pneumatic to hydraulic converter
NOTE For a typical system diagram, see Figure A.1.
3.1.2
pneumatic (full air) braking system
braking system in which the control and energy are transmitted from the point of application to the brakes by
pneumatic transmission devices
NOTE For a typical system diagram, see Figure A 2.
3.1.3
electronic braking system
EBS
braking system in which control is generated and processed as an electrical signal in the control transmission
NOTE Electrical output signals control devices, which produce actuation forces from stored pneumatic energy.
3.1.4
antilock braking systems
ABS
3.1.4.1
categories of ABS
⎯ Category 1: ABS which meets all the requirements of ECE R 13 Annex 13;
⎯ Category 2: ABS which meets the requirements of ECE R 13 Annex 13, except paragraph 5.3.5 of ECE
R 13 Annex 13 (no braking rate on split-adhesion surfaces is prescribed);
⎯ Category 3: ABS which meets the requirements of ECE R 13 Annex 13, except paragraphs 5.3.4 and
5.3.5 of ECE R 13 Annex 13 (all split adhesion tests are omitted).

1) To be published.
2 © ISO 2006 – All rights reserved

3.1.4.2
wheel control
3.1.4.2.1
directly controlled wheel
wheel whose braking force is modulated according to data provided at least by its own sensor
3.1.4.2.2
indirectly controlled wheel
wheel whose braking force is modulated according to data provided by sensor(s) of other wheel(s)
NOTE ABS with select-high control are deemed to include both directly and indirectly controlled wheels. In systems
with select-low control, all sensed wheels are deemed to be directly controlled wheels.
3.1.4.3
full cycling ABS
ABS which is repeatedly modulating the brake force to prevent the directly controlled wheels from locking
NOTE Brake applications where modulation only occurs once during the stop shall not be considered to meet this
definition.
3.2
vehicle loading
3.2.1
laden vehicle
vehicle laden so as to reach its maximum mass
3.2.1.1
laden motor vehicle other than semi-trailer tractor
vehicle laden to technically feasible maximum design total mass specified by the vehicle manufacturer and
acknowledged by the Technical Services
NOTE This mass may exceed the “maximum authorized total mass” permitted by national regulations. Mass
distribution on the axles is stated by the vehicle manufacturer. In the event of several load distribution patterns being
planned, the distribution of the maximum design total mass among the axles is such that the load on each axle is
proportional to the maximum load for each axle defined by the manufacturer.
3.2.1.2
laden semi-trailer tractor
vehicle laden as in 3.2.1.1, except that the load defined by the manufacturer may be repositioned halfway
between the fifth wheel coupling pin position and the centre-line of the rear axle(s), so as to compensate for
the dynamic load transfer from the semi-trailer
NOTE This additional load, representing the semi-trailer loading may be carried in a specially designed load frame.
3.2.2
unladen vehicle
3.2.2.1
unladen motor vehicle other than semi-trailer tractor
vehicle laden to complete vehicle kerb mass without load or occupant but with the fuel tank filled to at least
90 % of the capacity specified by the vehicle manufacturer at the start of test and complete with cooling fluid
and lubricants, and tools and spare wheel, if provided
NOTE During the tests, the fuel quantity in the fuel tank is maintained at least to 50 % of its capacity. An increase up
to 200 kg mass over this mass is allowed. This corresponds, for instance, to the driver, one observer and instrumentation.
If necessary, the appropriate vehicle mass may be removed. For a vehicle without body, the manufacturer declares the
minimum axle loads for a bodied vehicle.
3.2.2.2
unladen semi-trailer tractor
vehicle laden as in 3.2.2.1 including the fifth wheel coupling or an equivalent load (in value and in position)
3.3
Air system pressures
3.3.1
pressure indicated by manufacturer
reservoir pressure specified by the manufacturer from which it is possible to achieve the required efficiency for
service braking and which is the basis for the tests prescribed in 15.7.
3.3.2
maximum pressure
pressure available for normal operation:
⎯ cut-out pressure, in the case of an installation with a pressure regulating device; and
⎯ [90] % of the asymptotic pressure, in the case of an installation with a pressure-limited compressor.
3.3.3
minimum pressure
pressure available for normal operation:
⎯ cut-in pressure, in the case of an installation with a pressure regulating device; and
⎯ [90] % of the pressure indicated by the manufacturer, in the case of an installation with a pressure-limited
compressor.
3.4
vehicle types
vehicles subject to the European Agreement Concerning the International Carriage of Dangerous Goods,
e.g. ADR vehicles
4 Symbols
For the purposes of this International Standard the symbols given in Table 1 apply.
Table 1 — Symbols
Symbol Meaning Unit
a mean deceleration m/s
m
d mean fully developed deceleration m/s
m
E wheelbase m
ε the adhesion utilised by the vehicle: quotient of the maximum braking rate with the ABS
operative (z ) and the coefficient of adhesion (k)
AL
ε the ε value measured on axle i (in case of a power-driven vehicle with a category 3 ABS)
i
ε the ε value on the high adhesion surface
H
ε the ε value on the low adhesion surface
L
F actuating force N
F Normal reaction of road surface under dynamic conditions with the ABS operative N
dyn
F F on axle i N
idyn dyn
F normal reaction of road surface on axle i under static conditions N
i
F total normal static reaction of road surface on all wheels of power-driven (towing vehicles) N
M
4 © ISO 2006 – All rights reserved

Table 1 (continued)
Symbol Meaning Unit
a
F total normal static reaction of road surface on the unbraked and non-driven axles of the N
Mnd
power-driven vehicle
a
F total normal static reaction of road surface on the unbraked and driven axles of the power- N
Md
driven vehicle
a
F 0,01 F + 0,015 F (rolling resistance) N
Wm Mnd Md
2 2
g acceleration due to gravity (9,81 m/s) m/s
h height of centre of gravity specified by the manufacturer and agreed by the Technical m
Service conducting the approval test
h height of fifth wheel coupling (king pin) m
k
k coefficient of adhesion between tyre and road
k k -factor of one front axle
f
k k -value determined on the high adhesion surface
H
k k -value determined on axle i for a vehicle with a category 3 ABS
i
k k -value determined on the low adhesion surface
L
k value of adhesion for 100 % slip
lock
k k -factor of the power driven vehicle
M
k maximum value of the curve “adhesion versus slip”
peak
k k -factor of one rear axle
r
n number of brake applications
p maximum pressure supplied by the towing vehicle in the supply circuit for the trailer bar
max
p 65 % of p bar
1 2
p pressure level specified by the manufacturer enabling the prescribed performance of the bar
service braking system to be achieved
P mass of motor vehicle kg
M
P maximum permissible mass of the trailer allowed to be towed by the power-driven vehicle t
T
R ratio of k to k
peak lock
S stopping distance m
t, t , ∆t time interval s
i
t , t , t pump up times (ref. 9.2.1) min
1 2 3
t mean value of t s
m
t minimum value of t s
min
v vehicle speed km/h
v maximum speed of the vehicle km/h
max
v lower speed limit for the antilock energy consumption test km/h
u
V reservoir volume l
z braking rate
z braking rate of the vehicle with the ABS operative
AL
z mean braking rate
m
z maximum value of z
max
z mean braking rate of front axle
mf
z mean braking rate of rear axle
mr
z z of the power-driven vehicle on a “split-surface”
MALS AL
a
F and F : In case of two-axle power-driven vehicles these symbols may be simplified to corresponding F symbol.
Mnd Md i
5 Test site conditions
5.1 Test site
The test site should be of sufficient size, without obstacles, to provide a safe testing environment.
The test site shall have a road of sufficient length prior to the test area to enable the test speeds to be attained.
The test area should be of;
a) sufficient length to allow for poor braking performance; and
b) sufficient width to allow for poor directional stability under braking.
5.2 Road surface condition
5.2.1 Surface
5.2.1.1 The test area shall be a dry, smooth, hard-surface free of loose material providing a peak
coefficient of adhesion of about [0,8].
5.2.1.2 Additionally, for the testing of vehicle(s) equipped with an ABS a surface providing a peak
coefficient of adhesion k of [0,3] or less is needed. It shall be preceded and followed by a surface
peak
according to 5.2.1.1 of sufficient length on the approach side to enable the test speeds to be attained.
The ratio R = k /k and the adhesion vs. slip curve have to be available for this surface in line with
peak lock
ECE R 13, Annex 13, Appendix 4.
Until such test surfaces become generally available, tyres at the limit of wear, and higher values up to [0,4]
may be used. The actual value obtained and the type of tyres and surface shall be recorded.
For testing vehicles fitted with ABS of category 1 or 2, it is also necessary for a low adhesion surface (k ) to
L
have a high adhesion surface (k ) on at least one side to enable the split-adhesion tests to be performed.
H
Both surfaces shall be sufficiently wide to be able to determine, using the vehicle under test, the peak
coefficients of adhesion separately.
The above described surfaces shall be such that k is equal to or greater than [0,5], and k /k is equal to or
H H L
greater than [2]. If any doubt arises that this requirement is met (e.g. the high adhesion surface is wet), the
peak coefficients of adhesion shall be ascertained by using the procedure detailed in subclauses 12.2
and 12.4. However, the peak coefficients of adhesion shall always be measured when testing a vehicle fitted
with antilock brakes of category 1 to check the braking rate on the split surface (reference 13.1).
5.2.2 Gradient
5.2.2.1 Road surface shall be level with a tolerance of ± 1 % of the average gradient, measured over a
minimum distance of 50 m.
5.2.2.2 Type II and type IIA test site conditions
Table 2 — Type II and type IIA test site conditions
Gradient Length of gradient
% km
Type II 6 6
Type IIA 7 6
NOTE In support of the tests specified in 15.8, additional information regarding practical test site conditions can be
taken from ISO 12161, including a test procedure using a vehicle dynamometer test bench.
6 © ISO 2006 – All rights reserved

5.2.2.3 The parking braking system hill holding test may be conducted on an appropriate gradient or on a
level road as specified in 10.3 and 15.1.
5.2.3 Camber
The camber or transverse gradient across the road surface shall not exceed 2 %.
5.3 Ambient conditions
5.3.1 Wind speed
The tests must be performed when there is no wind liable to affect the results. The wind speed shall not
exceed an average of 5 m/s.
5.3.2 Air temperature
The air temperature shall be recorded in the test report.
6 General requirements
6.1 General test conditions to be followed during the determination of braking performance
a) vehicle speed (reference 6.11);
b) without exceeding the maximum permissible control force;
c) engine disconnected or connected (as prescribed);
d) without wheel-locking, except immediately before stopping unless specifically allowed;
e) without deviation of the vehicle from its course (steering corrections of less than 90° allowed, if not
otherwise specified);
f) loading condition: unless otherwise specified, all tests should be carried out with the vehicle laden and
unladen.
6.2 During all phases of the following test procedures, any unusual braking performance characteristics
and/or vehicle behaviour e.g. course deviation or abnormal vibration, shall be observed and reported.
6.3 During the tests with the engine connected on vehicles with a manual gearbox, the clutch may be
disengaged just before the vehicle stops to avoid the engine stalling.
6.4 Deceleration measurements used in the following test procedures, unless otherwise stated, refer to the
“mean fully developed deceleration” as defined in UN-ECE Regulation 13 Annex 4 paragraph 1.1.2.
6.5 Tests may be carried out under adverse conditions to avoid delays, but with due consideration for
safety. Such adverse conditions shall be reported. Any failed tests under such conditions shall be repeated
under the correct conditions, but not all tests need necessarily be repeated.
6.6 The recommended sequence of the tests is listed in Clause 7.
6.7 Full or partial re-tests, after a failed test or to test alternative braking system components, shall again
follow the recommended order (Clause 7), and with particular emphasis on the vehicle preparation and
bedding in procedures.
6.8 Control forces shall be applied rapidly, but without significant overshoot, and then be maintained
constant during the stop (if not otherwise specified). The use of an adjustable pressure regulating device is
recommended.
6.9 Skilled test drivers shall determine the optimum vehicle braking performance without wheel-locking
except immediately before stopping and without course deviation [see 6.1. item e) for allowable steering
correction] after appropriately familiarizing themselves with the vehicle braking, steering and suspension
systems.
6.10 All tests start with cold brakes except the hot performance tests. A brake is deemed to be cold when the
temperature measured on the disc or on the outside of the drum or on the brake linings is lower than [100] °C.
6.11 The speed of the vehicle before actuating the braking system control shall be stabilized at a level not
less than [98] % of the prescribed speed for the test in question unless there is any other overriding
requirement.
6.12 Where a vehicle is so constructed that its maximum speed is lower than that prescribed for any test, the
test shall be performed at the maximum speed of the vehicle.
6.13 Tests with the engine connected shall be carried out in the appropriate gear, defined as the highest
gear normally used at the specified speed without exceeding the manufacturer’s recommended maximum
engine speed.
6.14 Each specific failure mode appropriate to the vehicle braking equipment shall be considered and the
braking system shall be checked for the worst-case failure modes (for EBS see ECE R 13 Annex 18 reference
in 8.1.4 of this International Standard).
6.15 Where fault conditions are imposed on the braking system, they should be removed after the
appropriate test has been conducted and the correct operation of the braking system should then be verified.
7 Recommended sequence of the tests
7.1 Preparation and static checks and tests
Table 3 — Preparation and static checks and tests
No. Test Engine status Reference to this Reference to
International ECE R 13/09
Standard
1 Preparation (documents, instrumentation, 8 § 1-2
bedding etc.)
2 Static braking force 9.1.1 5.1.4.4
3 Control force vs. line pressure 9.1.2 A4 § 2.1.1
4 Pressures at the coupling heads 9.1.3 A10 § 3.1.3
5 Capacity of energy sources running 9.2 A7 § 2
6 Response time 9.3 A4 § 4
7 Automatic braking 9.4 5.2.1.18.4
8 Brake failure and defect warning signals 9.5 5.2.1.29
5.2.1.13
5.2.1.25.2.5
A13 § 4.1, 4.2,
4.5.2
9 Spring braking system 9.6 A8
10 Test of EBS operation with ignition off 9.7 5.2.1.27.1
8 © ISO 2006 – All rights reserved

7.2 Basic performance tests — Unladen
Table 4 — Basic performance tests — Unladen
No. Test Engine status Reference to this Reference to
International ECE R 13/09
Standard
1 Type 0 test disconnected 10.1 A4 § 1.4.2, 2.1.1
2 Type 0 test connected 10.2 A4 § 1.4.3
3 Dynamic test of the parking braking system disconnected 10.4 A4 § 2.2
(if applicable)
4 Parking braking system (hill holding) disconnected 10.3 not prescribed
5 Wheel locking sequence test disconnected 10.5 A10 § 3.1.4.2
7.3 Failure tests – Unladen
Table 5 — Failure tests – Unladen
No. Test Engine status Reference to this Reference to
International ECE R 13/09
Standard
1 Service braking system failure, type 0 test disconnected 11.1 A4 § 2.2 or 2.4
2 Failed load sensing device disconnected 11.2 A10 § 6
3 Failed energy source on vehicles equipped with 11.3 5.2.1.27.5-8
EBS
7.4 ABS tests — Unladen
Table 6 — ABS tests — Unladen
No. Test Engine status Reference to this Reference to
International ECE R 13/09
Standard
1 ABS failure disconnected 12.1 A13 § 4.5,
A4 § 2.4.1
2 Adhesion utilisation on high adhesion disconnected 12.3 A13 § 5.2
3 Determination of k disconnected 12.2 A13 § app. 2
Hpeak
4 Adhesion utilisation on low adhesion disconnected 12.4 A13 § 5.2
5 Determination of k disconnected 12.4 A13 § app. 2
Lpeak
6 Wheel behaviour tests disconnected 12.5.2.1 A13 § 5.3.1
7 Transition from high to low adhesion disconnected 12.5.2.2 A13 § 5.3.2
8 Transition from low to high adhesion disconnected 12.5.2.3 A13 § 5.3.3
9 Split adhesion test disconnected 12.5.3 A13 § 5.3.4
ABS cat. 1 or 2
7.5 ABS tests — Laden
Table 7 — ABS tests — Laden
No. Test Engine status
Reference to this Reference to
International ECE R 13/09
Standard
1 ABS failure disconnected 13
A13 § 4.5,
A4 § 2.4.1
2 Adhesion utilisation on high adhesion disconnected 13 A13 § 5.2
3 Determination of k disconnected 13 A13 § app. 2
Hpeak
4 Adhesion utilisation on low adhesion disconnected 13 A13 § 5.2
5 Determination of k disconnected 13 A13 § app. 2
Lpeak
6 Wheel behaviour tests disconnected 13 A13 § 5.3.1
7 Transition from high to low adhesion disconnected 13 A13 § 5.3.2
8 Transition from low to high adhesion disconnected 13 A13 § 5.3.3
9 Split adhesion test disconnected 13, 13.1 A13 § 5.3.4
ABS cat. 1 or 2
A13 § 5.3.5
ABS cat. 1
10 Energy consumption disconnected 13.2 A13 § 5.1
7.6 Failure tests — Laden
Table 8 — Failure tests — Laden
No. Test Engine status Reference to this Reference to
International ECE R 13/09
Standard
1 Service braking system failure, type 0 test disconnected 14.1 A4 § 2.2 or 2.4
2 Failed load sensing device disconnected 14.2 A10 § 6
3 Energy source failure disconnected 14.3 5.2.1.14
7.7 Basic performance tests — Laden
Table 9 — Basic performance tests — Laden
No. Test Engine status Reference to this Reference to
International ECE R 13/09
Standard
1 Parking braking system (hill holding) disconnected 15.1 A4 § 2.3.1-5
2 Electrical parking brake 15.1.3 5.2.1.26
3 Dynamic test of the parking braking system disconnected 15.2 A4 § 2.3.6 or 2.2
4 Wheel locking sequence test disconnected 15.3 A10 § 3.1.4.2
5 Type 0 test (plot deceleration vs. pressure) disconnected 15.4 A4 § 1.4.2, 2.1.1
6 Type 0 test connected 15.5 A4 § 1.4.3
7 Warning device tests disconnected 15.6 5.2.1.29
5.2.1.13
8 Capacity of energy storage devices disconnected 15.7 A7
9 Type II or II/A test connected 15.8 A4 § 1.6, 1.8, A5
10 Type 0 hot performance test (if the service disconnected 15.8.2.2.2 A4 § 1.6.3
braking system was used for type II test) 15.8.2.3.2
11 Type I test connected 15.9 A4 § 1.5.1
12 Type 0 hot performance (fade) test disconnected 15.9.5 A4 § 1.5.3.1
10 © ISO 2006 – All rights reserved

8 Vehicle preparation
8.1 Documents and basic data
NOTE The control of the data in the definitions in 3.2 and 3.3 are an integral part of the vehicle preparation.
The vehicle shall be verified based upon the documentation as follows:
8.1.1 Main technical data according to Annex 2 of ECE R 13.
8.1.2 Piping diagram, layout and list of the elements of the braking system.
8.1.3 Braking system data and performance calculation.
8.1.4 Documentation according to Annex 18 of ECE R 13, if the vehicle is equipped with EBS. This
documentation includes an explanation of design provisions guaranteeing compliance with all relevant parts of
ECE R 13 (paragraphs 5.2.1.8, 5.2.1.27 and 5.2.1.28) which deal with the special requirements for brake force
compensation, EBS and coupling force control. This documentation may also indicate the worst-case failures
for EBS.
8.1.5 Report/approval of EMC (if vehicle is equipped with an ABS or EBS) in accordance with ECE R 10/02.
8.1.6 Report (if vehicle is equipped with an electric control line) that the vehicle has been satisfactorily
tested to the method described in Annex 17 of ECE R 13.
8.2 Braking system condition and bedding
8.2.1 The braking system components shall be new, or capable of functioning as if new, and within the
vehicle manufacturer’s specifications.
8.2.2 The brake linings shall be bedded. Until a uniform procedure is established, the bedding of the service
and parking brake linings should be carried out according to the manufacturer’s recommendations.
The brake linings may be regarded as bedded if at least 80% of their surface contacts with the brake drums or
discs. Neither glazed, nor burned or damaged surfaces are acceptable.
8.3 Adjustment of braking equipment
Brake adjustment devices, including those in automatically adjusted brakes, shall be set according to the
vehicle manufacturer’s recommendations. Re-adjustment of the brakes may be made prior to each specific
test. The automatic adjustment of brakes is tested in 15.9.3, which takes place before the type I test.
8.4 Tyre conditions
8.4.1 The tyres shall be inflated to the vehicle manufacturer’s recommended pressure levels.
8.4.2 It is recommended that the tyre tread wear not exceed 50 % of the new condition, and that totally new
tyres not be used.
8.5 Devices and instruments needed for the testing
Care should be taken to ensure that instruments and devices added to the vehicle braking equipment do not
significantly affect braking system performance.
8.5.1 Additional devices for carrying out the testing of the braking systems
These consist of the following:
⎯ Pressure regulating/shut-off devices;
⎯ Air reservoir of 0,5 litre for trailer control line;
⎯ Air reservoir for simulation of trailer compressed air system capacity (9.2.2);
⎯ Signalling device (e.g. control lamp) to show functioning of the retarder and in case of integrated retarder
control, a means of disabling the retarder;
⎯ Towing vehicle for optional drag test(s).
8.5.2 Instrumentation
The test vehicle (and the towing vehicle if appropriate) shall be prepared for testing by the installation of
additional instruments and/or calibration of the existing standard vehicle instruments, as required.
All the instruments shall be checked to ensure correct function and, with the vehicle stationary on the test
surface, all the instruments shall be set.
It is recommended that the instrumentation include the following:
⎯ Control force gauges for the service braking system, for the parking braking system and for the secondary
braking system (if this system is not combined with either the service or the parking braking system);
⎯ Decelerometer;
⎯ Vehicle speed measuring and recording system;
⎯ Stopping distance measuring means;
⎯ Time measuring means;
⎯ Brake temperature indicating system;
⎯ Application and response time measuring equipment;
⎯ Line pressure gauges/transducers;
⎯ Towing force measuring system;
⎯ Wheel speed measuring and recording system;
⎯ Steering wheel angle indicator;
⎯ Optional instruments, which may include:
a) control travel gauges;
b) low to high adhesion surface transition indicator;
c) high capacity bi-directional ammeter (for EBS electrical tests, see 11.3.3.2).
8.5.3 Provision for failure simulation
The vehicle shall be equipped with the necessary added devices, piping and wiring as agreed with the vehicle
manufacturer to provide the required failure simulations.
12 © ISO 2006 – All rights reserved

8.5.3.1 In the pneumatic part of the braking system, a failure should correspond to an uncoupled pipe.
8.5.3.2 In the hydraulic part of the braking system, a leakage should be simulated with the brake fluid
being returned to its reservoir.
8.5.3.3 In the electric part of the braking system, a failure should generally correspond to a disconnection,
but a short circuit or a ground connection may be specified by the manufacturer in certain instances. This may
be done by using prepared components or sections of wiring.
9 Static tests and checks
9.1 Static braking force and control force vs. line pressure
9.1.1 Static braking forces
Determine maximum braking forces under static conditions on a rolling road or roller brake tester according to
ISO 21069-1 and ISO 21069-2.
9.1.2 Control force vs. control line pressure
Produce statically a graph of line pressure against increasing control force up to the maximum force/pressure
allowed for the service, secondary and parking braking functions. If the graphs are to be constructed from a
series of individual readings, then at least five readings should be taken, including the threshold value. Care
should also be taken to accurately depict any changes in the force-pressure relationship by taking additional
readings if necessary.
9.1.3 Pressures at the coupling heads
In the case of a power-driven vehicle authorized to tow trailers of category O3 or O4, fully apply the service
brake control with the system at cut-in and cut-out pressures and the energy source isolated. Check that the
pressures of both the pneumatic control and supply lines are between 0,65 MPa (= 6,5 bar) and 0,85 MPa
(= 8,5 bar) with a 0,5 litre volume connected to the control line, irrespective of the load condition of the vehicle.
With the reservoir at cut-in pressure, check that the supply line is at least at 0,7 MPa (= 7 bar) without the
application of the service brake.
When an electric control line is provided, the digital demand value according to ISO 11992 shall be fulfilled.
NOTE ISO 11992 defines the digital demand value such that 1 bit corresponds to 5/256 kPa, i.e. 33280d
corresponds to 0,65 MPa (6,5 bar).
9.2 Capacity of energy sources
9.2.1 Definitions
t is the time required for the pressure to rise from zero to p , measured in the braking energy reservoir
1 1
which shows the slowest pressure rise;
t is the time required for the pressure to rise from zero to p , measured in the braking energy reservoir
2 2
which shows the slowest pressure rise, where the vehicle is equipped with no pneumatic reservoir for
auxiliary equipment or with one or more pneumatic reservoirs for the same purpose, with a total capacity
not exceeding [20] % of the total capacity of the braking system pneumatic reservoirs;
t is the time required for the pressure to rise from zero to p , measured in the braking energy reservoir
3 2
which sho
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