Iveco TRALIS EBS2 Repair Manual
ELECTRONICALLY
CONTROLLED BRAKING
SYSTEM EBS 2/ESP/EBL
STRALIS AT/AD/AS
”This document provides data, characteristics, instructions and
methodology to perform repair interventions on the vehicle
and its components.
Anyhow, this document is addressed to qualified and
specialised personnel. Iveco commercial and assistance
network personnel as well as all Iveco authorised points of
assistance are specifically qualified and equipped to perform
the repair interventions that are indicated in this document.
Before performing any intervention, check to have available
the document relating to the vehicle model on which the
intervention is being performed and also make sure that all
accident prevention devices, such as, as a rough guide, goggles,
helmet, gloves, shoes, as well as work tooling, lifting and
transport tooling, etc., are available and efficient, and further
make sure that the vehicle is put such a way that an
intervention can be made in safety conditions.
Making interventions strictly observing the indications given
here, as well as using specific tooling indicated, assures a
correct repair intervention, execution timing observance and
operators’ safety.
Each repair intervention must be finalised to the recovery of
functionality, efficiency and safety conditions that are provided
by Iveco.
Each intervention, on the vehicle, that is finalised to a
modification, alteration or else, which is not authorised by
Iveco, involves the exclusion of any responsibility for Iveco,
and, in particular, where the vehicle is covered by a guarantee,
each such intervention involves an immediate lapse of the
guarantee.
Responsibility for Iveco in repair intervention execution is
excluded.
Iveco is available to provide all clarifications necessary to make
interventions, as well as to provide indications in cases and
situations not included in this document.
Data and information contained in this document could result
not to be updated owing to modifications made by Iveco at
any moment for technical or commercial reasons, or because
of the need to adapt the vehicle to law requirements in
different countries.
Inthecaseofadifferencebetweenwhatcontainedhereand
what actually found on the vehicle, please contact Iveco
network before making any intervention.”
The data contained in this publication might fail to reflect the
latest changes which the Manufacturer may introduce at any
time, for technical o r sales purposes, or to meet the
requirements of local legislation.
Copy, even partial, of text and drawings is forbidden.
Publication Edited by:
IVECO S.p.A.
Customer Service
Lungo Stura Lazio , 15
10156 Torino - Italia
Print 603.93.321 -1
st
Ed. 2004
Produced by:
B.U. TECHNICAL PUBLISHING
Iveco Technical Publications
Lungo Stura Lazio , 15
10156 Turin - Italy
STRALIS AT/AD/AS
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
Pneumatic system EBS 2/ESP/EBL brakes
SYMBOLS FOR AIR/HYDRAULIC SYSTEM
CIRCUIT DIAGRAMS
(TANKS AND ACCUMULATORS) 5..........
SYMBOLS FOR AIR/HYDRAULIC SYSTEM
CIRCUIT DIAGRAMS (VALVES) 6............
SYMBOLS FOR AIR-HYDRAULIC SYSTEM
DIAGRAMS (TANKS AND
ACCUMULATORS) 12......................
SYMBOLS FOR AIR/HYDRAULIC SYSTEM
CIRCUIT DIAGRAMS (CONVERTERS,
CYLINDERS AND CALLIPERS) 13.............
SYMBOLS FOR AIR/HYDRAULIC SYSTEM
CIRCUIT DIAGRAMS
(CALLIPERS AND CYLINDERS) 14............
1
Page
SYMBOLS FOR AIR/HYDRAULIC SYSTEM
CIRCUIT DIAGRAMS (SEMI-COUPLINGS
AND COUPLING CONNECTORS) 15.........
SYMBOLS FOR AIR/HYDRAULIC SYSTEM
CIRCUIT DIAGRAMS (SEMI-COUPLINGS
AND COUPLING CONNECTORS) 16.........
SYMBOLS FOR AIR/HYDRAULIC SYSTEM
CIRCUIT DIAGRAMS
(INDICATORS AND SWITCHES) 17..........
SYMBOLS FOR AIR/HYDRAULIC SYSTEM
CIRCUIT DIAGRAMS (BRAKES) 18............
PIPINGS AND FITTINGS 19....................
- In general 19.............................
- Rigid pipings reflanging 19...................
- Rigid pipings bending 20....................
- Rigid pipings cutting 20.....................
- Flexible pipings replacement with traditional
fittings 21...............................
- Flexible pipings replacement with quick
connection fittings 22......................
EBS 2 (ELECTRONIC BRAKE SYSTEM) 24.........
- EBS Benefits 24..........................
- Tractor and trailer compatibility at any time 24..
- Complete fault-diagnosis structures 24........
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2
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
S
TRALIS AT/AD/AS
OPERATING LOGIC 25.......................
BRAKE SYSTEM 25...........................
AUXILIARY BRAKE INTEGRATION 27...........
- ESP (Electron ic Stability Program) 28.........
“ABS-EBL” SYSTEM (ANTI-LOCK BRAKE SYSTEM —
ELECTRONIC BRAKE LIMITER) 28............
- “ABS” (Anti-Lock Brake System) 28..........
- EBL (Electron ic Brakes Limiter) 29............
- Operating Logic 29.......................
- Braking system evolution 29................
BRAKING SYSTEMS 30........................
Page
Page
- EBS 2 working diagram for 6x2 vehicles (trucks)
with CURSOR 10/13 engine 41.............
- EBS 2 working diagram for 6x2 vehicles (trucks)
with CURSOR 10/13 engine 42.............
- EBS 2 working diagram for 6x2 vehicles (trucks)
with CURSOR 10/13 engine 43.............
- EBS 2 system components location on vehicle
(tractors variant) 44.......................
- ABS-EBL system components location
(tractors variant) 45.......................
DESCRIPTION 46............................
- Service braking 46........................
- Emergency braking 46.....................
- Exhaust brake 46.........................
- Parking brake 46.........................
- ABS-EBL working diagram for 4x2 vehicles
(trucks and tractors, not inclu ding HR)
with CURSOR 8 (F2B) engine 30............
- Working diagram for 6x2 vehicles (tractors)
with CURSOR 8 (F2B) engine 31............
- ABS-EBL working diagram for 6x2 vehicles
(tractors) with CURSOR 8 (F2B) engine 32....
- Working diagram for 6x2 vehicles (trucks) with
CURSOR 8 (F2B) engine and with CURSOR 10
engine (F3A with mechanical suspensions) 33...
- ABS-EBL w orking diagram for 6x2 vehicles (trucks)
with CURSOR 8 (F2B) engine and w ith CURSOR 10
engine (F3A with mechanical suspensions) 34...
- ABS-EBL workin g diagram for stand alone 4x2
vehicles (trucks) with CURSOR 8 (F2B) engine 35
- ABS-EBL working diagram for 6x2C vehicles
(trucks) with CURSOR 8 (F2B) engine 36......
- ABS-EBL workin g diagram for stand alone 6x2
vehicles (trucks) with CURSOR 8 (F2B) engine 37
- EBS 2 working diagram for 4x2 vehicles (tractors)
with CURSOR 10/13 engine 38.............
BRAKES 46.................................
- Front an d rear disk brakes
(KNORR SN7 type) 46....................
FAULT DIAGNOSIS 47.......................
- Diagnosis Instruments 47...................
- Cluster Diagnosis 48......................
- EBS 2 theoretical scheme 63................
TIGHTENING TORQUES 68...................
TOOLS 70.................................
SPECIFICATIONS AND DATA -
PNEUMATIC SYSTEM 77....................
SPECIFICATIONS AND DATA - BRAKES 82......
CHECKS ON MAIN COMPONENTS
OF BRAKE SYSTEM 83......................
MAIN COMPONENTS OF THE BRAKING
SYSTEM 85...............................
- Compressor 85..........................
- EBS 2 working diagram for 4x2 T/FP-CT vehicles
- Head locking screw tigh tn ess 85.............
(tractors) with CURSOR 10/13 engine 39.....
- Fault diagnosis 86.........................
- EBS 2 working diagram for 6x2 vehicles (tractors)
with CURSOR 10/13 engine 40.............
Base - May 2004 Print 603.93.321
- A.P.U. (Air Processing Unit) 86..............
STRALIS AT/AD/AS
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
3
OPERATION 88.............................
- Duplex control valve (vehicles without EBS) 92.
- Fault Diagnosis (vehicles without EBS) 92......
- CBU (Central Brake Unit)
(vehicles with EBS 2) 93...................
- Relay valve (vehicles without EBS) 95.........
- Fault Diagnosis (vehicles without EBS) 95......
- Coupling heads 95........................
- Electropneumatic modulator
(vehicles with EBS 2) 96...................
- Operation 98............................
- Redundancy valve (for 4x2 and 6x2 trucks) 99..
- ABS solenoid valve 99.....................
- Dual stop valve 99........................
- Triple servo control valve
(vehicles without EBS) 99..................
- Predominance control 100..................
- Fault Diagnosis 100........................
- Trailer drive servo-assisted distributor
(vehicles with EBS 2) 101...................
Page
Page
- Speed sensor 107.........................
- Phonic wheels 107.........................
- Electronic control unit 107..................
- Pressure sensor 107........................
- Diaphragm brake cylinder (for fron t and
added front axle disc brake) 108..............
- Combined brake cylinder
(for front and rear disc brake) 108............
- Combined cylinder emergency brake
release device 109.........................
- Repairs 109..............................
- Fault Diagnosis 109........................
DISC BRAKES KNORR TYPE (CALIPER SN7) 110...
- Operation 111............................
CHECKS 111.................................
- Checking the automatic play recovery sy stem
efficiency 111.............................
- Brake caliper components 112...............
- Check of braking seals thickness 113...........
OVERHAULING FRONT DISC BRAKES 114........
- Operation 102............................
- Pressure test point valve 104.................
- Parking brake hand control valve
(vehicles suited to towing) 104...............
- Fault Diagn osis (parking brake control valve) 104.
- Parking brake control manual distributor
(standby vehicles) 105......................
- Manual control valve to slow down
the trailer (optional extra) 105...............
- Fault Diagn osis (parking brake control valve) 105.
- Controlled pressure valve 106................
- Fault Diagnosis 106........................
- Check valve (vehicles suited to towing) 106.....
- Low-pressure switch 106....................
- Electro-pneumatic valve for ASR 107..........
- Replacing brake lin ings 114..................
- Removing and refitting brake callipers 117.......
- Removal 117.............................
- Refitting 118..............................
- Removing and refitting wheel hubs 118.........
- Removal 118.............................
- Refitting 119..............................
BRAKE CALIPER OVERHAUL 120................
- Disassembly 120..........................
- Componentpartcleaningandcheck 121.......
- Assembly 121............................
OVERHAULING REAR DISC BRAKES 123.........
- Replacing brake lin ings 123..................
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4
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
S
TRALIS AT/AD/AS
OVERHAULING BRAKE DISCS 126...............
TURNING AND GRINDING BRAKE DISCS 126.....
Page
Base - May 2004 Print 603.93.321
STRALIS AT/AD/AS
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS
(TANKS AND ACCUMULATORS)
DESCRIPTION SYMBOL
HYDRAULIC FLOW
AIR FLOW
ELECTRICAL LINE
ABLE TO ROTATE
CROSSOVER OF CONNECTED LINES
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
5
PRESSURE TEST POINT
QUICK-CONNECTION COUPLING
COCK
COCK WITH OUTLET
SILENCER
COMPRESSOR
ENERGY SAVING COMPRESSOR
VACUUM PUMP
12
02
02
4
32
HYDRAULIC PUMP
02
HYDRAULIC HAND PUMP
32780
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6
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS (VALVES)
DESCRIPTION SYMBOL
CONDENSATE SEPARATOR
TRALIS AT/AD/AS
S
FILTER
DEHUMIDIFIER
DEHUMIDIFIER
DEHUMIDIFIER WITH BUILT-IN
REGULATOR
AUTOMATIC CONDENSATE
DRAIN VALVE
CONTROLLED CONDENSATE
DRAIN VALVE
HAND CONDENSATE DRAIN VALVE
CONTROLLED ANTI-ICING UNIT
12
12
4
21
1
22
21
1
22
23
7
12
AUTOMATIC ANTI-ICING UNIT
PRESSURE REGULATOR WITH
INDEPENDENT CIRCUIT
PRESSURE CONTROLLER
PRESSURE CONTROLLER
PRESSURE CONTROLLER
(GOVERNOR)
PRESSURE LIMITING VALVE
12
1
1
1
21
21
23
1
1
2
2
21
22
23
24
3278332782
Base - May 2004 Print 603.93.321
STRALIS AT/AD/AS
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS (VALVES)
DESCRIPTION SYMBOL
7
PROPORTIONAL REDUCING VALVE
MATCHING VALVE
FOUR CIRCUIT PROTECTION VALVE
THREE CIRCUIT PROTECTION
VALVE
TWO CIRCUIT PROTECTION VALVE
NON-RETURN AIR INLET VALVE
LIMITED RETURN AIR INLET VALVE
21
2
2
23
1
1
1
22
24
21
123
22
21
1
22
21
21
SAFETY VALVE
CHECK VALVE
CHECK VALVE
DOUBLE SHUT-OFF VALVE
DIFFERENTIAL DOUBLE SHUT-OFF
VALVE
THROTTLE VALVE WITH QUICK
RETURN
THROTTLE VALVE
21
2
2
1
2
11 12
U
MS
12
32783 32784 32785
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8
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS (VALVES)
DESCRIPTION SYMBOL
TRALIS AT/AD/AS
S
DUMP VALVE
BRAKE CONTROL VALVE
BRAKE CONTROL VALVE
BRAKE CONTROL VALVE
PARKING BRAKE CONTROL VALVE
A
P
21
2111
2212
2111
2111
4
2212
21
2211
PARKING BRAKE CONTROL VALVE
BRAKE VALVE
CONTROL VALVE
CONTROL VALVE
RETARDER CONTROL VALVE
SERVO CONTROL VALVE
R
21
21
21
21
221
2313
4
21
32786
Base - May 2004 Print 603.93.321
STRALIS AT/AD/AS
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS (VALVES)
DESCRIPTION SYMBOL
4241
SERVO CONTROL VALVE
21
4
SERVO CONTROL VALVE FOR
SINGLE LINE
TRAILER BRAKING TRIPLE
CONTROL VALVE
TRAILER BRAKING TRIPLE
CONTROL VALVE WITH BUILT-IN
SERVO SWITCHING
42
41 43
42
41 43
12
21
21
2211
9
LOAD PROPORTIONING VALVE
DUAL LOAD PROPORTIONING
VALVE
LOAD PROPORTIONING VALVE
WITH BY-PASS
LOAD PROPORTIONING VALVE
WITH BUILT-IN RELAY
LOAD PROPORTIONING VALVE
WITH BUILT-IN RELAY WITH AIR
CONTROL
21
2111
2212
12
21
11
1
2
4
4
1
2
4241
32787
32786
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10
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS (VALVES)
DESCRIPTION SYMBOL
TRALIS AT/AD/AS
S
LOAD PROPORTIONING VALVE
WITH AIR CONTROL
LOAD PROPORTIONING VALVE
WITH AIR CONTROL
PROPORTIONAL REDUCING VALVE
SLAVED PROPORTIONAL
REDUCING VALVE
STROKE LIMITING VALVE
12
4241
1
2
4
1 2
4
1
2
2
1
LEVELLING VALVE
LEVELLING VALVE
LEVELLING VALVE WITH BUILT-IN
TRAVEL LIMITER
HAND OPERATED SUSPENSION
RAISING CONTROL VALVE
1
21 22
12
12 23
11
21
2423
21 22
32788
32787
Base - May 2004 Print 603.93.321
STRALIS AT/AD/AS
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS (VALVES)
DESCRIPTION SYMBOL
2
PROPORTIONAL CONTROL VALVE
1
13
HAND OPERATED SUSPENSION
CONTROL VALVE WITH
ELECTRICAL MONITORING
12 22
42
41
2111
11
ELECTROPNEUMATIC VALVE
ELECTROPNEUMATIC VALVE
ELECTROPNEUMATIC VALVE
HYDRAULIC MODULATOR FOR ABS
AUGMENTER VALVE
1
3
12
12
21
1
VR HZ2
ABS
22
HZ1VL
HL HR
4
1
2
32788
Print 603.93.321 Base - May 2004
12
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
TRALIS AT/AD/AS
S
SYMBOLS FOR AIR-HYDRAULIC SYSTEM DIAGRAMS (TANKS AND ACCUMULATORS)
DESCRIPTION SYMBOL
COMPRESSED AIR TANK
BRAKE FLUID RESERVOIR
AIR SPRING
32789
Base - May 2004 Print 603.93.321
STRALIS AT/AD/AS
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS
(CONVERTERS, CYLINDERS AND CALLIPERS)
DESCRIPTION SYMBOL
VACUUM BRAKE SERVO
VACUUM BRAKE SERVO
DUAL CIRCUIT MASTER CYLINDER
SINGLE CIRCUIT MASTER CYLINDER
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
13
AIR/HYDRAULIC CONVERTER
AIR/HYDRAULIC CONVERTER
HYDRAULIC BRAKE CYLINDER
SLAVE CYLINDER
BRAKE CYLINDER
SPRING CYLINDER
COMBINED BRAKE CYLINDER
FIXED DISC BRAKE CALLIPER
3279132790
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14
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS
(CALLIPERS AND CYLINDERS)
DESCRIPTION SYMBOL
FLOATING DISC BRAKE CALLIPER
FLOATING DISC BRAKE CALLIPER
WITH PARKING
MECHANICAL FLOATING DISC
BRAKE CALLIPER
SERVO CLUTCH
TRALIS AT/AD/AS
S
SERVO CLUTCH
32791
Base - May 2004 Print 603.93.321
STRALIS AT/AD/AS
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS
(SEMI-COUPLINGS AND COUPLING CONNECTORS)
DESCRIPTION SYMBOL
A
“ISO” SEMI-COUPLING
M
ISO VERSION
A
“ISO” SEMI-COUPLING
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
15
“CUNA” SEMI-COUPLING
“CUNA” SEMI-COUPLING
M
VERSION WITH ISO COUPLINGS
A
B
ITALIAN VERSION
M
A
A
“NATO” SEMI-COUPLING
M
NATO VERSION
32793
32792
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16
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS
(SEMI-COUPLINGS AND COUPLING CONNECTORS)
DESCRIPTION SYMBOL
4
1
5
23
V
Z
A
SINGLE LINE VERSION
A
M
SEMI-COUPLING
V
Z
A
TRALIS AT/AD/AS
S
SEMI-COUPLING
SEMI-COUPLING
SINGLE LINE VERSION
12
22
4
2
SINGLE LINE VERSION
12
22
4
1
2
SINGLE LINE VERSION
A
M
32793
Base - May 2004 Print 603.93.321
STRALIS AT/AD/AS
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS
(INDICATORS AND SWITCHES)
DESCRIPTION SYMBOL
PRESSURE GAUGE
PRESSURE GAUGE
PRESSURE SENDING UNIT
LAMP
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
17
MECHANICAL SWITCH
PRESSURE SWITCH
LOW PRESSURE SWITCH
AUDIBLE WARNING
SENSOR
32794
Print 603.93.321 Base - May 2004
18
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
SYMBOLS FOR AIR/HYDRAULIC SYSTEM CIRCUIT DIAGRAMS (BRAKES)
DESCRIPTION SYMBOL
SINGLE CYLINDER HYDRAULIC
BRAKE
TWIN CYLINDER HYDRAULIC BRAKE
DUAL SERVO HYDRAULIC BRAKE
DUAL SERVO HYDRAULIC BRAKE
WITH PARKING BRAKE
TRALIS AT/AD/AS
S
SINGLE CAM OPERATED BRAKE
TWIN DUAL CAM OPERATED BRAKE
32795
Base - May 2004 Print 603.93.321
STRALIS AT/AD/AS
799512 PIPINGS AND FITTINGS
In general
Hydraulic system pipings for industrial vehicles are currently of
two types:
- Flexible ones made of polyamide with single-layered or
double-layered structure and in the following diameters
(∅ 6-8-10-12-16 mm) equipped with spares in meters.
- Rigid metal pipings in the following diameters
(∅ 4.75-6.35-8-10-12 mm). Pipings from ∅ 4.75 to
∅ 10 mm are supplied as spares in straight 4-5-6 m crop
ends, while those exceeding 10 mm are supplied as spares
already cut, bent and reflanged.
Rigid pipings reflanging
Figure 1
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
Figure 3
31973
Burr piping (1), insert union (2) and place it between small
blocks (3) abutting pin (5). Lock piping (1) with screw (4).
Figure 4
19
A
B
C
RIGID PIPINGS REFLANGING REPRESENTATION
Reflanging type A
Figure 2
31971
31974
Take back pin (4) to its neutral position. Screw screw (1) till
matrix die (2) comes to abut against small blocks (3) thereby
shaping the piping (5) end.
Reflanging type B
Figure 5
31972
Arrange on a press 99386523 (3) small blocks (1) so that the
punched numbers, showing the piping number to be worked,
are facing the matrix die (2). The choice of the matrix die (2)
depends on the diameter of the piping to be reflanged.
Moreover, on every matrix die (2) the diameter of the piping
is punched for which the same one can be used.
Print 603.93.321 Base - May 2004
Assemble matrix die (2) on press 99386523 (1).
For the reflanging process comply with what has been stated
above for reflanging type A.
31975
20
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
TRALIS AT/AD/AS
S
Reflanging type C
Figure 6
Key on piping (1) nut (2) and ring (3).
Figure 7
Figure 9
31979
31976
Place piping (1) into tool (3) and operating on lever (2) bend
the piping.
Figure 10
31977
Assemble union (2) and tighten so that ring (3, Figure 6) is
locked on piping (1).
Rigid pipings bending
Figure 8
31978
Assemble tool (1) 99386523 choosing parts (2) and (3)
depending on the diameter of pipings to be bent.
31980
In order to free piping (2) from tool (3), operate on lever (1).
Rigid pipings cutting
Figure 11
31981
Place piping (2) into tool (3) 99386523 and tighten screw (1).
Keeping piping (2) still, rotate tool (3) till the piping is
completely cut.
Base - May 2004 Print 603.93.321
STRALIS AT/AD/AS
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
21
After having cut the piping, burr and shape the end as
previously described.
Rotating tool (3) around piping (2), screw (1) is
loosened. In order to completely cut the piping, it is
!
then necessary to tighten screw (1) when it
loosening.
Flexible pipings replacement with traditional fittings
Strictly comply with the following instructions:
Figure 12
10397
- Use homologated pipes only;
- Check the spare pipe status, on which no cracks, cuts or
nickings must be detected;
- Cut the pipe at 90° with respect to the axis through a
suitable pipe-cutting pliers 99387050 at the necessary
length;
Insert on the pipe in the following order:
- nut (3), pressure ring (2) (its greater thickness must be
facing nut (3) and reinforcement bush (1));
- the bush must be in perfect conditions (it must not have
either distortions or hammering traces).
- Carry out abutment ring reflanging upon assembly on the
vehicle or work bench on a fitting.
- The exerted pressure and the final distance from front
pressure ring edge to reinforcement bush edge must be
those mentioned in the table below.
In case of a bad assembly, never use the pipe after
having extracted bush and abutment ring.
!
Pipe
mm
6x1
Distance between
bush edge and ring
mm (*)
from 1 to 1.5
Assembling
pressure
2
N/mm
0.040
Double-
layered
Single-
8x1
10 x 1.5
12 x 1.6
from 2 to 2.5
from 2 to 2.5
from 2 to 2.5
0.050
0.050
0.060
layered
16 x 2.34
(*) See reference h, Figure 14.
from 3 to 3.5
0.060
Figure 14
Figure 13
10399
1. Reinforcement bush - 2. Pressure ring -
3. Nut - 4. Fitting - 5. Pipe -
10398
REINFORCEMENT BUSH ASSEMBLY
A = CORRECT ASSEMBLY
B = WRONG ASSEMBLY
- Key the reinforcement bush with tool 99372219
guaranteeing the contact between its flange and the pipe
end;
- make sure that the pipe end penetrates into the suitable
rake groove obtained in the flange.
Print 603.93.321 Base - May 2004
h. Distance between bush edge and ring edge (see table).
Insert the thereby-prepared piping end into the fitting body till
the reinforcement bush flange rests within the suitable seat:
- For closing the nut on the fitting, initially screw it manually
and then complete the tightening with a suitable box
wrench (complete series 99372221) inserted into the
dynamometric wrench, to be calibrated according to the
required tightening torque.
22
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
TRALIS AT/AD/AS
S
Assembly of piping on vehicle is carried out by taking into
account some important solutions:
- Bendings must comply with minimum radiusses, in order
to avoid throttlings.
Pipings diameter
mm
6x1
8x1
10 x 1.5
12 x 1.6
16 x 2.34
Minimum bending radius
mm
approx. 40
approx. 50
approx. 60
approx. 75
approx. 100
Make sure that pipings are not in contact with sharp
edges or with cutting metallic parts or with heat
!
sources, but that are distant therefrom by a minimum
safety distance of 15 mm.
- Moreover,when crossing chassis longitudinal members or
metallic parts, check that passage holes are coated with
rubber fairlead rings and that these latter ones are in good
conditions;
- Avoid that the pipe slides along cutting edges that would
risk to create nickings;
- Having to fix the piping onto already existing ducts, take
into account the supplementary heat to which it can be
subjected (hydraulic power steering duct): in such case,
the piping must be protected with guards;
- At the end of the connection, verify that the piping,
between keying and securing, is not stretched, but must
be slightly loosened to recover higher temperature
variations, particularly for short lengths;
- Before assembling, accurately clean the pipings by blowing
compressed air in order to guarantee system operation.
Flexible pipings replacement with quick connection fittings
Rotating fittings
Figure 16
39306
Screw the fitting in the threaded seat provided on the
pneumatic valve and lock it at the tightening torque shown in
the table.
Swinging fittings
Figure 17
39307
Figure 15
- Check that the sealing ring (1) is into its suitable seat;
- screw the fitting till it is felt that the sealing gasket abuts
onto the valve;
- adequately swing the fitting and keeping the swingable
part still, lock the hexagonal nut at the tightening torque
mentioned in the table.
13132
- Protect the pipes in case of grinding or welding
operations on the vehicle; for such purpose, an adhesive
plate is applied in the cabin and shows the precautions to
be observed with utmost care to avoid damages.
Rotating and swinging fittings
FITTING TIGHTENIG TORQUE (Nm ± 10%)
THREADING
M10x1.0mm
M12x1.5mm
22
24
For better safety and work comfortability, it is
advisable to detach the pipings during such operations.
!
At the end of the assembly, check the perfect seal of all gaskets
(unions, fittings, etc.).
Base - May 2004 Print 603.93.321
M14x1.5mm
M16x1.5mm
M22x1.5mm
28
35
40
STRALIS AT/AD/AS
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
23
Figure 18
33977
- Use homogated pipes only;
- Check the spare pipe status, on which no cracks, cuts or
nicking must be detected;
- Cut the pipe at 90° with a max 15° error with respect to
the axis through the suitable pipe-cutting pliers 99387050
at the necessary length;
Figure 19
Figure 20
39308
- Manually insert pipe (2) into fitting (1), with a force varying
from 30 to 120 N depending on pipe diameter, so that the
notch L
is placed inside the fitting while the notch L2is
1
visible.
Figure 21
A
33976
A = Marking to identify pipe end-of-stroke
- Strongly and indelibly mark with ink two reference
notches on both diametrically-opposed pipe faces for an
angle ≥ 75°, placed at the distances of L
guarantee a correct assembly.
Dimensions L1and L2change depending on the pipe
diameter and must be measured from the longest
!
pipe part (see Figure 18).
D
(mm)
6
L
(mm)
19.8
0
+0.5
L
1
(mm)
17
-0.5
+1
and L2to
1
L
2
(mm)
22
-0.5
+1
33978
In case of disassembling of fittings (1) from pneumatic
components, check the sealing ring (2) status, and if necessary
replace it.
FITTING SEALING RINGS
THREADING DIMENSIONS
M 10 x 1.0
M 12 x 1.5
M 14 x 1.5
M 16 x 1.5
M 22 x 1.5
10.1 x 1.6
11.0 x 2.0
-
15.0 x 2.0
-
Every time a piping is detached from a quick
connection fitting, it is necessary to replace the fitting
!
itself. Quick connection fittings are supplied complete
as spares.
8
12
20.5
25
18
22
23
28
Quick connection and threaded fittings, as well as
flexible pipings used with quick connection fittings
!
and flexible pipings used with threaded fittings, are
16
Print 603.93.321 Base - May 2004
27.1
24
30
not interchangeable.
24
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
TRALIS AT/AD/AS
S
EBS 2 (ELECTRONIC BRAKE S YSTEM)
The increase in competition in the transport sector has had the effect, among others, of constantly increasing the basic requirements
of braking systems.
The introduction of the EBS electronic brake system is the logical answer to these new needs.
It is an integrated and permanent electronic control system for the brake system of the tractor and trailer.
It supplements the ABS, ASR and EBL functions.
The system is made up of a pneumatic system and an electric system. In the system there is inserted the CBU (central brake unit),
component integrating:
- Duplex distributor, which generates electric and pneumatic signals to increase or decrease pressure in the braking system;
- electronic central unit, which has the task of managing the braking system determining deceleration values as a function of
parameters detected from various components;
- proportional relay valve, which modulates pressure at front axle.
The EBS system dialogues with the control units of the other assemblies:
Engine, Ecas, retarder and gearbox via the CAN line (VDB, Vehicle Data Bus).
EBS Benefits
Lower servicing costs.
The EBS combines many functions. The aim is to cut maintenance costs while maximizing braking safety — that is minimizing brake
lining wear.
An individual control according to the lining wear parameters on both the front and rear axles harmonizes lining wear. Distributing
the load homogeneously between all the brakes of the wheels reduces total consumption. In addition, the frequency of servicing
and changing the linings coincide. The costs of inactivity are drastically reduced.
Depending on the servicing a vehicle needs along with other factors, the owner may be able to make considerable savings. A
comparison of the maintenance costs, for the brake system, of a vehicle with EBS and one with a conventional brake system highlights
significant savings.
Tractor and trailer compatibility at any time
Harmonizing the braking processes of the entire tractor-trailer combination, especially if the combinations are frequently changed,
often with conventional means, is not satisfactory.
An inadequate balance, such as with a trailer whose braking is not sufficiently effective, will cause uneven wear of the brake linings.
The EBS will recognize all the incompatibilities between tractor and trailer, harmonizing braking automatically. When the brakes work
in the best conditions, not only are brake maintenance costs optimized, but safety and comfort are optimum too.
Complete fault-diagnosis structures
The EBS provides the owner of the vehicle with constantly updated information on the state of the brake system and the basic brakes.
This makes it possible to schedule servicing in advance. The EBS monitors all the fundamental components and functions of the brake
system.
Any defect recognized by the system is accurately highlighted. The maintenance specialist can therefore rectify the error at issue.
The high degree of safety ensured by the EBS is due to several factors:
- Lower pressure accumulation and response times for the brakes on the front, rear and trailer axles.
- Better ABS function.
- Tractor/trailer always balanced in every moment.
- Constant monitoring of the service brake system. In the event of reduced brake performance, the EBS will be able to warn the
driver.
- The integrated ASR function permits optimum vehicle stability and drive optimization.
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STRALIS AT/AD/AS
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
OPERATING LOGIC
The purpose of the electronic control unit is to slow down the vehicle as quickly as possible, ensuring its stability and avoiding the
tendency for the wheels to lock.
To achieve this aim, while braking, the electronic control unit will be informed of the:
- required deceleration via the sensors inside the duplex control valve;
- pressures made available via the pressure sensors in the components;
- reaction on slowing down due to the pressures made available via the speed sensor signals.
The continuous monitoring and processing of this information, in relation to the set aim, will cause the modulating valves to activate
appropriately and optimize the braking action accordingly.
25
IN
Required deceleration
Braking pressure
Wheel speed
Graduated release trailer pressure
CONTROL UNIT
AIM
n Slip = 0
BRAKE SYSTEM
In a dynamic situation the effect on the vehicle will be managed in this way:
Figure 22
OUT
FRONT AXLE pressure
REAR AXLE pressure
77208
Ca. Front axle load - Cp. Rear axle load - Cr. Load on fifth wheel - Da. Front axle braking force -
Dp. Rear axle braking force - Dm. Braking force at graduated release - Ds. Semitrailer braking force -
Ffa. Resultant of braking/front axle load - Ffp. Resultant of braking/rear axle load - Ffm. Resultant of braking/load
at graduated release - Ffs. Resultant of braking/semitrailer load - a. Braking angle - Rr. Reaction on the fifth wheel -
Dec. Required deceleration - g. Acceleration due to gravity - z. Braking ratio
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26
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
TRALIS AT/AD/AS
S
Generally, the EBS will tend to apply a braking force in proportion to the load on the axles, that is to maintain the same angle ”α”
for all the axles:
Da
Ca
Dp
=
Cp
=
Ds (Dm)
Cs (Cr)
=
Tag α α =
dec
=z
g
Therefore, such force will be larger as compared to required deceleration.
This, as may be seen, also holds for the semitrailer control.
If the reaction on the fifth wheel ”Rr” is not as expected, the system automatically increases or decreases the predominance at the
graduated release and ”Ffm” accordingly so as to ensure the best compatibility between the tractor and semitrailer in compliance
with current type-approval standards, as may be seen in the following compatibility diagram.
Figure 23
000987t
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STRALIS AT/AD/AS
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
27
AUXILIARY BRAKE INTEGRATION
Commercial vehicles are normally fitted with auxiliary brakes for slowing down without causing wear, such as the exhaust brake and
intarder.
On vehicles equipped with the EBS, these devices can be integrated to ensure the vehicle slows down sooner and more effectively.
The exhaust brake/intarder action percentage is set by the driver with the lever.
The exhaust brake will be applied up to a speed of 1000 rpm, while the action of the retarder will cause the following action depending
on the position of the lever:
Figure 24
Position 0 — disengaged
001685t
Position 1 — E.B. 100%
Position 2 — E.B. 100% + Intarder 25% (20% *)
Position 3 — E.B. 100% + Intarder 50% (40% *)
Position 4 — E.B. 100% + Intarder 75% (60% *)
Position 5 — E.B. 100% + Intarder 100% (80% *)
Position 6 — E.B. 100% + Intarder 100%
These applications, always possible, will be signalled to the driver by the relevant indicator lights coming on.
* Vehicles with mechanic gearbox.
On vehicles without the optional Intarder, the auxiliary brake lever has just three positions: off, E.B. 50%, E.B. 100%.
!
On vehicles fitted with a EuroTronic gearbox, with the auxiliary brake lever on position 6, slowing down will be more
effective with the automatic gear shift down.
Switching the engine off for longer than one minute involving a change in load, tyres or ratios at the rear axle causes the adjustment
data to be lost and so a fresh period of data acquisition will be necessary for the system to be able to reactivate auxiliary brake
integration if no vehicle parameter is changed the integration will be immediately available.
If manually activating the auxiliary brakes, the next time the brake pedal is pressed will implement integration.
On releasing the brake pedal, if the manual action is compatible with the calculated action it will be kept active.
If activating the auxiliary brakes, both manual and integrated, causes the rear axle to slow down too much and a tendency for it to
lock, the EBS control unit, on detecting this situation via the speed sensors, will immediately disengage them or turn on the auxiliary
brake Slip Control.
Print 603.93.321 Base - May 2004
28
AIR SYSTEM - BRAKES EBS 2/ESP/EBL
TRALIS AT/AD/AS
S
ESP (Electronic Stability Program)
ESP function, joined to EBS abilities, controls vehicle lateral dynamics.
The main objectives of this function are:
- Improving stability, most of all in both understeering and oversteering conditions
- Reducing braking spaces in change of line conditions on slippery roads
Main central unit input data in order to achieve following objectives, are:
- signal from steering angle sensor (mounted on the steering wheel)
- signals from y aw speed and lateral acceleration sensors (integrated into the ESP module, that is mounted on the chassis and
also contains a part o f ESP software).
In order to avoid control loss, the ESP will automatically activate the brakes of one wheel per axle only trying to take the vehicle
back to correct direction. In this case, the ESP controls towing body skidding angle and slant, as well as the shift between driver’s
request and actual vehicle yaw speed. To the purpose of withstanding vehicle deceleration, the driving torque will be decreased.
In yaw control mode, the ESP very carefully controls driver’s reactions and always tries to provide relevant support.
Note: ESP function is optionally available on tractors only.
Figure 25
89009
1. ESP module - 2. Reference pin for mounting to support bracket.
“ABS-EBL” SYSTEM (ANTI-LOCK BRAKE SYSTEM — ELECTRONIC BRAKE LIMITER)
EBL function controls rear axle wheel “skidding” by comparing it to front axle wheel speed.
On the basis of wheel r.p.m.’s and braking pressure (detected by the sensor upstream from rear axle ABS modulators), the central
unit calculates vehicle speed, rear axle wheel “skidding” and minimum acceleration expected.
“ABS” (Anti-Lock Brake System)
The braking of a m oving vehicle and the according deceleration and stopping distances depend above all on the grip between the
surfaces of the tyres and the road.
With a fully efficient braking system, a further improvement in braking can only be achieved by acting on the friction of the tyres
or on the grade of the road surface.
Even in these optimum conditions, absolute braking safety is anyhow not guaranteed when faced with especially tricky situations,
such as poor grip due to a wet or icy road surface: the driver is forced to moderate use of the brakes in order to avoid partially
locking one or more wheels, with the risk of skidding dangerously.
The function of the ”ABS” is therefore to ensure vehicle stability (in all braking conditions), preventing the wheels from locking
irrespective of the state of the road surface, so as to ensure the available grip is made full use of.
Even in the case of e mergency braking, the system makes it possible to keep direction, that is to turn the steering wheel to avoid
obstacles with no risk of skidding.
In short, the anti-lock brake system (ABS):
- Prevents the wheels locking when the vehicle is braking, no matter what grip is available on the road.
- Shortens stopping distances.
- Provides safety for the driver who can keep the vehicle’s stability and direction.
Base - May 2004 Print 603.93.321
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