ISO 11992-2:2014

DRAFT INTERNATIONAL STANDARD ISO/DIS 11992-2
ISO/TC 22/SC 3 Secretariat: DIN
Voting begins on Voting terminates on

2011-12-12 2012-15-12
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION  •  МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ  •  ORGANISATION INTERNATIONALE DE NORMALISATION

Road vehicles — Interchange of digital information on electrical
connections between towing and towed vehicles —
Part 2:
Application layer for brakes and running gear
Véhicules routiers -- Échange d'informations numériques sur les connexions électriques entre véhicules
tracteurs et véhicules tractés —
Partie 2: Couche d'application pour les équipements de freinage et les organes de roulement
[Revision of second edition (ISO 11992-2:2003) and ISO 11992-2:2003/Amd.1:2007]
ICS 43.040.15
In accordance with the provisions of Council Resolution 15/1993 this document is circulated in
the English language only.
Conformément aux dispositions de la Résolution du Conseil 15/1993, ce document est
distribué en version anglaise seulement.

To expedite distribution, this document is circulated as received from the committee
secretariat. ISO Central Secretariat work of editing and text composition will be undertaken at
publication stage.
Pour accélérer la distribution, le présent document est distribué tel qu'il est parvenu du
secrétariat du comité. Le travail de rédaction et de composition de texte sera effectué au
Secrétariat central de l'ISO au stade de publication.

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REFERRED TO AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.
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©  International Organization for Standardization, 2011

ISO/DIS 11992-2
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ii © ISO 2011 – All rights reserved

ISO/DIS 11992-2
Contents Page
Foreword . iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 3
5 General Specifications . 4
6 Application layer . 5
6.1 Protocol Data Unit (PDU) specification . 5
6.2 Parameter Group Number (PGN) . 7
6.3 Address assignment . 7
6.4 Message routing . 9
6.5 Parameters . 11
6.6 Messages . 63
7 Conformance tests . 82
7.1 General . 82
7.2 Conformance tests for commercial vehicles . 82
7.3 Conformance tests for towed vehicles . 83
Annex A (normative) Geometric data . 84
Annex B (informative) Message Flow . 88
Bibliography . 94

ISO/DIS 11992-2
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 11992-2 was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 3,
Electrical and electronic equipment.
This third edition cancels and replaces the second edition (ISO 11992-2:2003) and its amendment 1 of which
have been technically revised.
ISO 11992 consists of the following parts, under the general title Road vehicles — Interchange of digital
information on electrical connections between towing and towed vehicles:
⎯ Part 1: Physical layer and data-link layer
⎯ Part 2: Application layer for brakes and running gear
⎯ Part 3: Application layer for equipment other than brakes and running gear
⎯ Part 4: Diagnostics
iv © ISO 2011 – All rights reserved

ISO/DIS 11992-2
Introduction
This part of the internation standard has been established in order to define the data interchange between a
commercial vehicle and its towed vehicle(s), including communication between towed vehicles, using a
Controller Area Network (CAN) serial data link as specified in ISO 11992-1 for control and status data related
to electronical controlled braking and running gear applications.
It is subject to additions which will become necessary in order to keep pace with experience and technical
advances. Care has been taken to ensure that these additions can be introduced in a compatible way, and
care will have to be taken in the future so that such additions remain compatible with previous versions. In
particular, it may become necessary to standardize new parameters and parameter groups. ISO members can
request that such new parameters and parameter groups to be included in future editions of ISO 11992.

DRAFT INTERNATIONAL STANDARD ISO/DIS 11992-2

Road vehicles — Interchange of digital information on electrical
connections between towing and towed vehicles —
Part 2:
Application layer for brakes and running gear
1 Scope
This part of the ISO 11992 international standard specifies the parameters and messages for electronically
controlled braking systems, including ABS (anti-lock braking systems) and VDC (vehicle dynamics control
systems) as well as for running gear equipment (i.e. systems for steering, suspension and tyres), to ensure
the data communication interchange of information between road vehicles with a maximum authorized total
mass greater than 3500 kg, and their towed vehicles, including the communication between (several) towed
vehicles, on a dedicated network. It does not include any other communication on that network that is not
related to communication between those vehicles.
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 7638, Road vehicles — Connectors for the electrical connection of towing and towed vehicles —
Connectors for braking systems and running gear of vehicles
ISO 11898-1, Road vehicles — Controller area network (CAN) — Part 1: Data link layer and physical
signalling
ISO 11992-1, Road vehicles — Interchange of digital information on electrical connections between towing
and towed vehicles — Part 1: Physical layer and data-link layer
ISO 11992-4, Road vehicles — Interchange of digital information on electrical connections between towing
and towed vehicles — Part 4: Diagnostics
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 11992-1, ISO 11898-1 and the
following apply.
3.1
ABS
This definition is used for a control function to support anti-lock braking (anti-lock braking system). It is also
used for control systems providing an anti-lock braking function.
3.2
ASR
This definition is used for a control function to support traction control (anti-spin regulation).
ISO/DIS 11992-2
3.3
Centre-axle trailer
This term is used for a towed vehicle equipped with a towing device which can not move vertically (in relation
to the trailer), and in which the axle(s) is(are) positioned close to the center of gravity of the trailer.
3.4
Commercial vehicle
This term is used for a vehicle that is engine driven and capable of towing other vehicles; same as a truck or
tractor.
3.5
EBS
This definition is used for a control system providing an electronically controlled braking that contains
functions like ABS, ASR, VDC.
3.6
ECU
This term is used for an electronic control unit.
3.7
Drawbar trailer
This term is used for a towed vehicle with one axle group or single axle at the front that is steered by
connection to the towing vehicle by a drawbar and one axle group or single axle at the rear. This vehicle may
also be a towing type.
3.8
Dolly
This term is used for a towed vehicle with one axle group or single axle, and a fifth wheel coupling, designed
to convert a semi trailer into the equivalent of a full trailer.
3.9
Gateway
This term is used for a network node that is able to filter and forward messages to different network segments.
3.10
Link trailer
This term is used for a towed vehicle with a fifth wheel coupling, designed for towing a semi trailer.
3.11
Network segment
This term is used for an electrical connection between one group of logically combined nodes of a
communication network.
3.12
Node
This term is used for an electronic device providing means to receive and transmit messages.
3.13
RGE
This definition is used for running gear equipment of a vehicle, including steering, suspension and tyres.
3.14
ROP
This definition is used for a control function to prevent roll-over situations of a vehicle (roll-over prevention /
protection), part of a VDC function.
NOTE In UNECE Regulation No. 13 Roll-over Prevention is referred to as Roll-over Control.
2 © ISO 2011 – All rights reserved

ISO/DIS 11992-2
3.15
Semi-trailer
This term is used for a towed vehicle with one axle group or single axle at the rear and a means of attachment
to a tractor that results in some of the load being imposed on the tractor.
3.16
Towed vehicle
This term is used for any type of vehicle that is actually being towed by another vehicle; usually these are
trailers or dollies.
3.17
Towing vehicle
This term is used for any type of vehicle that is actually towing another vehicle; usually these are commercial
vehicles (tractors) or a trailer or dolly towing another trailer
3.18
VDC
This definition is used for a control function as part of the braking system that reacts to stabilise the vehicle
during dynamic manoeuvres (Vehicle Dynamic Control) with the possible sub-functions ROP, YC.
3.19
YC
This definition is used for a control function to reduce unwanted lateral movement of a vehicle (yaw control),
part of a VDC function
NOTE In UNECE Regulation No. 13 Yaw Control is referred to as Directional Control.
4 Symbols and abbreviated terms
CAN Controller Area Network
CAN-ID CAN Identifier
DA Destination Address
DLC Data Length Code
DP Data Page
EDP Extended Data Page
GE Group Extension
LSB Least Significant Byte (or Bit)
MSB Most Significant Byte (or Bit)
P Priority
PDU Protocol Data Unit
PF PDU Format
PGN Parameter Group Number
PS PDU Specific
ISO/DIS 11992-2
SA Source Address
UTC Universal Time Coordinate
5 General Specifications
The data link shall be in accordance with ISO 11898-1; the physical layer shall be in accordance with
ISO 11992-1.
Appropriate PDUs are specified to structure the communication between towing and towed vehicle
interface(s). These PDUs shall be transmitted between electronic devices (nodes) at the towing vehicle and
each towed vehicle as defined in the following sections.
Each node at a vehicle shall provide logical separation between the network segments and any in-vehicle
networks and act as a gateway to forward the messages as specified in the following sections.
Any combination of new and old towing and towed vehicles is allowed. Multiple towed vehicles may be
connected in any combination; the network shall be capable of addressing any towed vehicle, including
dollies. The truck operator may disconnect and connect towed vehicles at any time and any order and the
network shall adjust and respond accordingly.
4 © ISO 2011 – All rights reserved

ISO/DIS 11992-2
6 Application layer
6.1 Protocol Data Unit (PDU) specification
6.1.1 General
The application layer provides a string of information that is assembled as a PDU. The PDU provides a
framework for organizing the information sent by means of CAN data frames.
All transmitted CAN data frames shall use the extended data frame format with a 29-bit CAN-ID as defined in
ISO 11898-1. The PDU framework is the same as defined in SAE J1939-71 [2].
The PDU shall consist of the fields as shown in Figure 1, which are
⎯ a 29-bit CAN-ID with the sub-fields Priority (P), Extended Data Page (EDP), Data Page (DP), PDU
Format (PF), PDU Specific (PS) — which may be a Destination Address (DA) or a Group
Extension (GE) —, and Source Address (SA),
⎯ a 64-bit data field.
MSB 29-bit CAN-ID bit position LSB CAN data field byte position
bit/byte
28 26 25 24 23 16 15 8 7 0 1 2 3 4 5 6 7 8
position
Data field
P EDP DP PF PS SA
number
3 1 1 8 8 8 64
of bits
Figure 1 — PDU structure
Depending on the contents of the sub-fields the PDUs are classified as PDU1 or PDU2 frames as given in the
following definitions.
6.1.2 Priority (P)
This 3-bit sub-field shall be used to optimize PDU frame latency for transmission onto the bus only and shall
have no other specific meaning. It shall not be used for message validation on receiver side and should be
globally masked off by the receiver (ignored). The priority of any PDU may be set from highest, 0 (000 ), to
10 2
lowest, 7 (111 ) and will use this default values:
10 2
⎯ The default for all control oriented PDUs shall be 3 (011 ).
10 2
⎯ The default of all other informational PDUs shall be 6 (110 ).
10 2
⎯ The default for diagnostic PDUs shall be 7 (111 ).
10 2
6.1.3 Extended Data Page (EDP)
This 1-bit sub-field shall be used in conjunction with the DP sub-field to select an auxiliary range of PGNs. The
definition of a PGN is given in clause 6.2. This bit shall always be set to zero.
6.1.4 Data Page (DP)
This 1-bit sub-field shall be used to select an auxiliary range of PGNs. The definition of a PGN is given in
clause 6.2.
ISO/DIS 11992-2
6.1.5 PDU Format (PF)
This 8-bit sub-field shall determine the PDU format and the transmission method as specified in Table 1.
⎯ If the value of the PDU format field is below 240, then the PDU format is of type PDU1 and the PDU-
specific field contains a destination address.
⎯ If the value of the PDU format field is 240 to 255, then PDU format is of type PDU2 and the PDU-specific
field contains a group extension.
Table 1 — PDU definition
PDU
PF value PS Transmission method
format
This PDU 1 format shall be used for messages to be sent directly to either a
0 to 239 PDU1 DA
specific or a global destination.
This PDU 2 format shall only be used to communicate global (broadcast)
240 to 255 PDU2 GE
messages.
6.1.6 PDU Specific (PS)
6.1.6.1 General
This 8-bit sub-field shall depend on the PDU format. For a PDU1 format the PDU specific (PS) sub-field is a
destination address (DA), for a PDU2 format the PS sub-field is a group extension (GE) (see Table 1).
6.1.6.2 Destination Address (DA)
The DA shall contain the specific address of the towing or towed vehicle to which the PDU is being sent. If the
global destination address (255 = FF ) is sent, all nodes shall process the PDU.
10 16
6.1.6.3 Group Extension (GE)
The GE in conjunction with the four least significant bits of the PF sub-field shall be used as part of the
specific PGN.
6.1.7 Source Address (SA)
This 8-bit sub-field shall provide the source address (SA) of the node that transmits the PDU. Therefore the
SA sub-field assures that the CAN-ID is unique on all network segments.
6.1.8 Data field
All CAN data frames shall use a data field length of 8 byte, i.e. DLC=8. If less than 8 byte are required by the
defined PGN all non-used bits shall be transmitted with all bits set to 1.
6 © ISO 2011 – All rights reserved

ISO/DIS 11992-2
6.2 Parameter Group Number (PGN)
This 24-bit number shall be used in all cases where a group of parameters assembled in the PDU data field
need to be identified. A PGN is built from the CAN-ID sub-fields EDP, DP, PF and PS as specified in Figure 2
and is used to identify or label a group of parameters. It is independent of the remaining fields of the CAN-ID.
The upper bits 18 to 23 are reserved and shall always be set to zero (0). For a PDU1 message, i.e. if the PS
field is a DA, the least significant byte (PS) of the PGN shall always be set to zero (0).
MSB    LSB
byte position 2 1 0
bit position 23 18 17 16 15 8 7 0
000000 EDP DP PF PS
Number of bits 6 1 1 8 8
Figure 2 — PGN sub-field definition
NOTE To reduce the effort of exchanging PDUs between the ISO 11992-2 communication and any in-vehicle
network, the PGNs within this standard are harmonized with those used in SAE J1939.
EXAMPLE For a message with CAN-ID 18FEC920 (PDU2 format) the sub-fields are P= 110 , EDP= 0 , DP= 0 ,
16 2 2 2
PF= FE , PS= C9 , SA= 20 . The corresponding PGN is 00FEC9 (65225 ).
16 16 16 16 10
6.3 Address assignment
6.3.1 Address usage
A road-train consists of one truck (commercial vehicle) and one or more trailer(s) (towed vehicles). Dollies
within the road train shall be treated as additional towed vehicles (see Figure 3).
The commercial vehicle is the towing vehicle of towed vehicle #1; towed vehicle #1 is the towing vehicle of
towed vehicle #2; and so on.
12 3 4
Key:
1 truck / commercial vehicle (position #0)
2 trailer / towed vehicle position #1
3 dolly / towed vehicle position #2
4 trailer / towed vehicle position #3
Figure 3 — Example of a possible road train configuration

ISO/DIS 11992-2
For towing vehicle/towed vehicle communication, each node shall use only the addresses given in Table 2 as
SA and DA for all messages.
Table 2 — Commercial vehicle / towed vehicle addresses
name address predecessor successor
commercial vehicle (#0) 32 / 20 n/a towed vehicle #1
10 16
towed vehicle #1 200 / C8 commercial vehicle (#0) towed vehicle #2
10 16
towed vehicle #2 192 / C0 towed vehicle #1 towed vehicle #3
10 16
towed vehicle #3 184 / B8 towed vehicle #2 towed vehicle #4
10 16
towed vehicle #4 176 / B0 towed vehicle #3 towed vehicle #5
10 16
towed vehicle #5 168 / A8 towed vehicle #4 undefined
10 16
global destination address 255 / FF undefined undefined
10 16
The global destination address shall only be used by the commercial vehicle to broadcast information to all
towed vehicles simultaneously.
6.3.2 Address assignment procedure
The address of the commercial vehicle is fixed. The respective address of a towed vehicle corresponds to its
position within the road train and shall be (re-) assigned each time
⎯ communication starts, or
⎯ the towed vehicle has been connected to the road train.
The dynamic address assignment shall be handled by the respective towing vehicle/towed vehicle node and
concerns the determination of the individual position within the road train. It is based on transmission of the
general initialization message (see clause 6.6.4.1) by the respective predecessor within the road-train.
Within a road-train, the address assignment procedure shall be initiated by the commercial vehicle, using its
default address for the general initialization message. A powered-up towed vehicle node shall use the towed
vehicle #1 address as the default address for transmitting available information until the general initialization
message has been received from the towing vehicle and a valid address can be assigned.
Each towed vehicle node shall use the general initialization message received at the towing vehicle network
interface to determine its own address. It shall use the successor's address of that message's SA as its own
address. This requires that a towed vehicle node shall be capable of
⎯ identifying its predecessor by the SA of the general initialization message,
⎯ assigning its own address based on the predecessors address, and
⎯ identifying potential receiver(s) by the destination address and by the message type.
An assigned address shall be valid as long as the towed vehicle is powered and no message from the
predecessor with a different SA is received. If a different SA is received the assignment procedure shall be
restarted.
To provide address assignment for itself and for possible successors, a node shall be capable of continuously
sending the general initialization message with its dynamically assigned own SA as illustrated in Figure 4.
This addressing method allows the towed vehicle node to communicate and to identify its presence to its
predecessor immediately after power-up. This means that several towed vehicles can use the same address
until the address assignment procedure is completed. Continuous sending of the general initialization
message is necessary to allow immediate towed vehicle address assignment at any time a towed vehicle
might be connected.
8 © ISO 2011 – All rights reserved

ISO/DIS 11992-2
Commercial vehicle Trailer #1 Trailer #2 Trailer #3 Trailer #4 Trailer #5
Sends SA=commercial vehicle to sucessor
SA =
Commercial
Receives SA = commercial vehicle from pred.
vehicle
Claims SA = towed vehicle #1
Sends SA = Towed vehicle #1 to successor
SA =
Towed
Receives SA = towed vehicle #1 from pred.
vehicle #1
Claims SA = towed vehicle #2
Sends SA = Towed vehicle #2 to successor
SA =
Receives SA = toved vehicle #2 from pred. Towed
Caims SA = towed vehicle #3 vehicle #2
Sends SA = Towed vehicle #3 to successor
SA =
Receives SA = towed vehicle #3 from pred.
Towed
Claims SA = towed vehicle #4
vehicle #3
Sends SA = Towed vehicle #4 to successor
SA =
Receives SA = towed vehicle #4 from pred. Towed
Claims SA = towed vehicle #5
vehicle #4
Figure 4 — Address assignment procedure

6.4 Message routing
If a vehicle has no provision for a successor, the message routing function is not required by the vehicle's
node.
To allow communication between towing and towed vehicles, a node shall be capable of
⎯ receiving messages from its predecessor and successor within the road-train,
⎯ identifying receiver(s) by the destination address (PDU 1 type messages) or the PDU format (PDU 2 type
messages),
⎯ routing all applicable messages from its predecessor(s) to its successor(s) within the road-train by
sending them with the unchanged SA and DA to its successor within a maximal delay time of t = 13 ms,
d
⎯ routing all applicable messages from its successor(s) to its predecessor(s) within the road-train by
sending them with the unchanged SA and DA to its predecessor within a maximal delay time of
= 13 ms.
t
d
A towed vehicle node shall not route messages to its successor or predecessor within the road-train,
⎯ if the SA of a message received from its predecessor corresponds to a road-train position closer or equal
to its own to the commercial vehicle, or
ISO/DIS 11992-2
⎯ if the SA of a message received from its successor corresponds to a road-train position more distant or
equal to its own from the commercial vehicle.
EXAMPLE Figure 5 shows some examples of message flow between vehicles

Commercial vehicle Towed vehicle #1 Towed vehicle #2 Towed vehicle #3
PDU 1 type messages from towing
vehicles to succeeding towed
vehicles
PF = PF =
PF =
PS = DA[towed vehicle #2] PS = DA[towed vehicle #3]
PS = DA[towed vehicle #1]
SA = commercial vehicle SA = towed vehicle #1 SA = towed vehicle #2
PDU 1 type message from
PF =
commercial vehicle to towed vehicle
PS = DA[towed vehicle #2]
PF =
#2
SA = commercial vehicle No transmission
PS = DA[towed vehicle #2]
SA = commercial vehicle
PDU 2 type message from PF =
PF =
commercial vehicle to all towed PS =
PS =
vehicles SA = commercial vehicle
PF =
SA = commercial vehicle
PS =
SA = commercial vehicle
PDU 1 type messages from towed
vehicles to preceding towing vehicles
PF = PF = PF =
PS = DA[commercial vehicle] PS = DA[towed vehicle #1] PS = DA[towed vehicle #2]
SA = towed vehicle #1 SA = towed vehicle #2 SA = towed vehicle #3
PF =
PF =
PS = DA[commercial vehicle]
PDU 1 type message from towed
PS = DA[commercial vehicle]
SA = towed vehicle #3
vehicle #3 to commercial vehicle
PF =
SA = towed vehicle #3
PS = DA[commercial vehicle]
SA = towed vehicle #3
PDU 2 type message from towed
PF =
vehicle #2
PS = No transmission
PF =
SA = towed vehicle #2
PS =
SA = towed vehicle #2
Figure 5 — Example of message flow between vehicles

10 © ISO 2011 – All rights reserved

ISO/DIS 11992-2
6.5 Parameters
6.5.1 Generic data ranges
Each defined parameter shall comply with one of the defined parameter types
⎯ Table 3 specifies the ranges used to determine the validity of transmitted signals.
⎯ Table 4 specifies the ranges used to denote the status of a discrete parameter.
⎯ Table 5 specifies the ranges used to denote the status of a control mode command.
The values in the range "error indicator" provide a means for a module to immediately indicate that valid
parameter data is not currently available, owing to some type of error in the sensor, subsystem or module.
Additional information about the failure may be available using diagnostic communication.
The values in the range "not available" provide a means for a module to transmit a parameter that is not
available or not supported in that module. This value does not replace the "error indicator".
The values in the range "not requested" provide a means for a device to transmit a command message and
identify those parameters where no response is expected from the receiving device.
The values in the range of "special function" are reserved for definition of parameter specific functionalities.
For some parameters non generic definitions are given in the following sections. These are not defined here.
Examples are encoded table values, where each value is assigned to one specific meaning.
After power-on, a node shall internally set the "availability bits" of received parameters as "not available" and
operate with default values until valid data is received. When transmitting, undefined bytes shall be sent as
255 (FF ) and undefined bits shall be sent as "1".
10 16
If a failure of a function or device prevents the transmission of valid data for a parameter, the error indicator,
as specified in Table 3, Table 4 or Table 5, shall be used in place of that parameter data. However, if the
measured or calculated data has yielded a value that is valid yet exceeds the defined parameter range, the
error indicator shall not be used. The data shall be transmitted using the appropriate minimum or maximum
parameter value.
A 2-byte (16 bit) parameter shall be sent least significant byte first, most significant byte second.
Table 3 — Transmitted signal ranges
Range name 1 byte 2 byte
0 to 250 0 to 64255
10 10 10 10
Valid signal
0 to FA 0 to FAFF
16 16 16 16
Reserved for future 251 to 253 64256 to 65023
10 10 10 10
indicators FB to FD FB00 to FDFF
16 16 16 16
254 65024 to 65279
10 10 10
Error indicator
FE FE00 to FEFF
16 16 16
Not available or 255 65280 to 65535
10 10 10
not requested FF FF00 to FFFF
16 16 16
ISO/DIS 11992-2
Table 4 — Transmitted values for discrete parameters (measured)
Range name Transmitted value
Disabled (off, passive, insufficient) 00
Enabled (on, active, sufficient) 01
Error indicator 10
Not available or not installed 11
Table 5 — Transmitted values for control requests (status)
Range name Transmitted value
Comand to disable function (turn off, etc.) 00
Comand to enable function (turn on, etc.) 01
Special function (parameter specific) 10
Don't care/ take no action (leave function as it is) 11
6.5.2 General parameter specification
A description of each parameter is given in clauses 6.5.3, 6.5.4, and 6.5.5. The description includes data
length, data type, resolution and range for reference.
The type of data shall also be identified for each parameter. Data may be either status or measured.
⎯ Status specifies a command requesting an action to be performed by the receiving node. Examples of
status-type data are "service brake demand value" and "ride height request".
⎯ Measured data conveys the current value of a parameter as measured or observed by the transmitting
node to determine the condition of the defined parameter. Examples of measured type data are "wheel-
based vehicle speed" and "lift axle 1 position". Note that a measured type parameter can indicate the
condition of the defined parameter, even if no measurement has been taken. For example, the measured
type parameter can indicate that a solenoid has been activated, even if no measurement has been taken
to ensure the solenoid accomplished its function.
For each parameter the attributes given in Table 6 shall apply.
Table 6 — attribute definiton
Attribute definition
Data length Required number of bits/bytes of the parameter
Resolution Weight of a bit in physical unit
Offset Value of the binary value 0 (zero) in physical unit
Data range Physical range of data the parameter is able to hold
Operating range Physical range of data that may be used
Type Type of data as specified in this section
PGN reference: Reference to the PGN(s) where the parameter is used

The PGN reference attribute is informative. The PGN parameters are specified normative in subclause 6.6.
12 © ISO 2011 – All rights reserved

ISO/DIS 11992-2
6.5.3 System independent parameters
6.5.3.1 Tyre/wheel identification
This parameter shall indicate the identification number of the tyre or wheel. The identification number shall
specify the tyre or wheel position on each axle (Bit 1 to Bit 4) and the number of axles starting from the front of
the respective towed vehicle (Bit 5 to Bit 8) (see Figure 6).
The tyre/wheel identification shall only be used as complementary information in conjunction with all tyre,
wheel or wheel-end related information in the PGN's message and shall be ignored if that parameters are not
supported. The identification number "0" shall be used if the position of the tyre, wheel, wheel-end or axle
cannot be identified. Table 7 specifies the parameter description.
Table 7 — specification of parameter tyre/wheel identification
Attribute Value
Data length 1 byte
encoded table value
Bit 1 to bit 4
0000  – wheel position undefined
Resolution 0001 to 1111 – wheel position 1 to 15
2 2
Bit 5 to bit 8
0000  – axle position undefined
0001 to 1111 – axle position 1 to 15
2 2
Type Measured
PGN 65222 — EBS23 — Electronic brake system #2/3
PGN reference: PGN 65116 — RGE22 — Running gear equipment #2/2
PGN 65118 — RGE23 — Running gear equipment #2/3

Assingment rules
⎯ The tyre/wheel identification shall be assigned sequentially from the vehicle's centre line starting from "9"
incrementing on the right side and from "7" decrementing on the left side, in the normal direction of travel.
"8" is used for one wheel on the centre line as illustrated in Figure 6.
⎯ It is assumed that each wheel rim has one, and only one, tyre.
⎯ In situations where the number of wheels on each wheel-end cannot be identified, or the wheel-end alone
is to be identified, the parameters shall be identified using the default wheel position 7 left and 9 right in
the normal direction of travel.
⎯ In cases where the wheel definition is shared, within the same PGN, with another parameter or
parameters, the wheel-end may be specified as a wheel position 1 to 7 on the left hand side or 9 to 15 on
the right hand side, as required by the other parameter or parameters.
⎯ In situations where more than 15 axles are present on the vehicle, the first 15 axles shall be identified
using this procedure; the additional axles shall then be identified with the axle identification "0" together
with the respective wheel identification.
NOTE Due to the parameter definition there is an ambiguity between 'parameter not supported' (255 ) and
wheel = 15 and axle = 15 . As the identification number serves only as complementary information for other parameters
10 10
the value of 255 identifies only a valid position if those parameters are supported.
ISO/DIS 11992-2
driving direction
0 8 F (= 15)
(1,7) (1,9)
(2,7) (2,9)
(3,6) (3,7) (3,9) (3,A)
(4,8)
Figure 6 — Tyre/wheel and axle position

6.5.3.2 Seconds
This parameter shall indicate the component 'seconds' of the current time of day. This should be reported as
the seconds of the current time at UTC; however, it may be reported as the component seconds of the current
time at a local time zone. The local hour / minute offset parameters (subclause 6.5.3.8, 6.5.3.9) are used to
indicate if the time of day is the current UTC time or a local time zone time. Table 8 specifies the parameter
description.
Table 8 — specification of parameter seconds
Attribute Value
Data length 1 byte
Resolution 0,25 s / bit
Offset 0 s
Data range 0 to 62,5 s
Operating range 0 to 59,75 s
Type Measured
PGN reference: PGN 65254 — TD11 — Time/Date #1/1

6.5.3.3 Minutes
This parameter shall indicate the component 'minutes' of the current time of day. This should be reported as
the minutes of the current time at UTC; however, it may be reported as the component minutes of the current
time at a local time zone. The local hour / minute offset parameters (subclause 6.5.3.8, 6.5.3.9) are used to
indicate if the time of day is the current UTC time or a local time zone time. Table 9 specifies the parameter
description.
14 © ISO 2011 – All rights reserved

F (= 15)                                   0

ISO/DIS 11992-2
Table 9 — specification of parameter minutes
Attribute Value
Data length 1 byte
Resolution 1 min / bit
Offset 0 min
Data range 0 to 250 min
Operating range 0 to 59 min
Type Measured
PGN reference: PGN 65254 — TD11 — Time/Date #1/1

6.5.3.4 Hours
This parameter shall indicate the component 'hour' of the current time of day. This should be reported as the
hours of the current time at UTC; however, it may be reported as the component hours of the current time at a
local time zone. The local hour / minute offset parameters (subclauses 6.5.3.8, 6.5.3.9) are used to indicate if
the time of day is the current UTC time or a local time zone time. Table 10 specifies the parameter description.
Table 10 — specification of parameter hours
Attribute Value
Data length 1 byte
Resolution 1 h / bit
Offset 0 h
Data range 0 to 250 h
Operating range 0 to 23 h
Type Measured
PGN reference: PGN 65254 — TD11 — Time/Date #1/1

6.5.3.5 Day
This parameter shall indicate the component 'day' of the current time of day. This should be reported as the
day of the current time at UTC; however, it may be reported as the component day of the current time at a
local time zone. The local hour / minute offset parameters (subclauses 6.5.3.8, 6.5.3.9) are used to indicate if
the time of day is the current UTC time or a local time zone time. Table 11 specifies the parameter description.
Table 11 — specification of parameter day
Attribute Value
Data length 1 byte
Resolution 0,25 day / bit
Offset 0 day
Data range 0 to 62,50 day
Operating range 0,25 to 31,75 day
Type Measured
PGN reference: PGN 65254 — TD11 — Time/Date #1/1

NOTE A value of 0 for the day is null. The values [1, 2, 3, 4] indicate the first day of a month, the values [5, 6, 7, 8]
indicate the second day of the month, etc.
ISO/DIS 11992-2
6.5.3.6 Month
This parameter shall indicate the component 'month' of the current time of day. This should be reported as the
month of the current time at UTC; however, it may be reported as the component month of the current time at
a local time zone. The local hour / minute offset parameters (subclauses 6.5.3.8, 6.5.3.9) are used to indicate
if the time of day is the current UTC time or a local time zone time. Table 12 specifies the parameter
description.
Table 12 — specification of parameter month
Attribute Value
Data length 1 byte
Resolution 1 month / bit
Offset 0 month
Data range 0 to 250 month
Operating range 1 to 12 month
Type Measured
PGN 65254 — TD11 — Time/Date #1/1
PGN reference:
PGN 35072 — RGE24 — Running gear equipment #2/

NOTE A value of 0 is null. A value of 1 identifies January, 2 identifies February, etc.
6.5.3.7 Year
This parameter shall indicate the component 'year' of the current time of day. This should be reported as the
year of the current time at UTC; however, it may be reported as the component year of the current time at a
local time zone. The local hour / minute offset parameters (subclauses 6.5.3.8, 6.5.3.9) are used to indicate if
the time of day is the current UTC time or a local time zone time. Table 13 specifies the parameter description
Table 13 — specification of parameter year
Attribute Value
Data length 1 byte
Resolution 1 year / bit
Offset 1985 year
Data range 1985 to 2235 year
Operating range 1985 to 2235 year
Type Measured
PGN 65254 — TD11 — Time/Date #1/1
PGN reference:
PGN 35072 — RGE24 — Running gear equipment #2/

NOTE A value of 0 identifies year 1985, 1 identifies year 1986, etc.
6.5.3.8 Local minute offset
This parameter shall indicate the component 'minute' of the offset between the UTC time and date and a local
time zone time and date and is defined as the number of minutes to add to UTC time and date to convert into
the time and date of local time zone.
⎯ The local offset is a positive value for time zones east of the Prime Meridian to the International Date
Line.
⎯ The local offset is a negative value for time zones west of the Prime Meridian to the International Date
Line.
16 © ISO 2011 – All rights reserved

ISO/DIS 11992-2
The local minute offset is only applicable when the time and date parameters are reported as UTC time and
date. Table 14 specifies the parameter description.
Table 14 — specification of parameter local minute offset
Attribute Value
Data length 1 byte
Resolution 1 min / bit
Offset - 125 min
Data range - 125 min to 125 min
Operating range - 59 min to 59 min
Type Measured
PGN reference: PGN 65254 — TD11 — Time/Date #1/1

6.5.3.9 Local hour offset
This parameter shall indicate the component 'hour' of the offset between the UTC time and date and a local
time zone time and date and is defined as the number of hours to add to UTC time and date to convert intto
the time and date of local time zone.
⎯ The local offset is a positive value for time zones east of the prime Prime Meridian to the International
Date Line.
⎯ The local offset is a negative value for time zones west of the Prime Meridian to the International Date
Line.
The local hour offset is only applicable when the time and date parameters are reported as UTC time and
date. Table 15 specifies the parameter description.
Table 15 — specification of parameter local hour offset
Attribute Value
Data length 1 byte
Resolution 1 h / bit
Offset -125 h
Data range - 125 h to 125 h
Operating range - 23 h to 23 h
Type Measured
PGN reference: PGN 65254 — TD11 — Time/Date #1/1
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