ISO 11992-4:2023

Road vehicles — Interchange of digital information on electrical connections between towing and towed vehicles — Part 4: Diagnostic communication

This document specifies diagnostic application requirements and OSI-layer related communication profiles to ensure the interchange of digital information between towing and towed vehicles with a maximum authorized total mass greater than 3 500 kg. The conformance and interoperability test plans are not part of this document.

Véhicules routiers — Échange d'informations numériques sur les connexions électriques entre véhicules tracteurs et véhicules tractés — Partie 4: Communication de diagnostic

General Information

• Status: Published
• Publication Date: 13-Apr-2023
• ICS: 43.040.15 - Car informatics. On board computer systems
• Technical Committee: ISO/TC 22/SC 31 - Data communication
• Drafting Committee: ISO/TC 22/SC 31/WG 4 - Network applications
• Current Stage: 6060 - International Standard published
• Start Date: 14-Apr-2023
• Due Date: 02-Jul-2023
• Completion Date: 14-Apr-2023

Relations

• Revises: ISO 11992-4:2014 - Road vehicles — Interchange of digital information on electrical connections between towing and towed vehicles — Part 4: Diagnostic communication
• Effective Date: 23-Apr-2020

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 11992-4
Third edition
2023-04
Road vehicles — Interchange of digital
information on electrical connections
between towing and towed vehicles —
Part 4:
Diagnostic communication
Véhicules routiers — Échange d'informations numériques sur
les connexions électriques entre véhicules tracteurs et véhicules
tractés —
Partie 4: Communication de diagnostic
Reference number
ISO 11992-4:2023(E)
© ISO 2023

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ISO 11992-4:2023(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
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Published in Switzerland
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ISO 11992-4:2023(E)
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms.2
4.1 Symbols . 2
4.2 Abbreviated terms . 2
5 Conventions . 2
6 Vehicle network architecture .3
7 Non OSI-layer-related technical requirements overview . 4
8 Abstract service primitive interface (ASP) definition . 5
8.1 ASP – A_Data.req, A_Data.ind, and A_Data.con service primitive interface . 5
8.2 ASP – Service interface parameters . 6
8.2.1 General . 6
8.2.2 ASP – Data type definitions . 7
8.2.3 ASP – Mtype, message type . 7
8.2.4 ASP – TAtype, target address type . 7
8.2.5 ASP – AE, address extension . 7
8.2.6 ASP – TA, target address . 7
8.2.7 ASP – SA, source address . 7
8.2.8 ASP – Length, length of PDU. 8
8.2.9 ASP – PDU, protocol data unit . 8
8.2.10 ASP – Result, result . 8
9 Application .8
9.1 APP – Addressing of requested information . 8
9.2 APP – Data identifier (DID) definition . 8
9.3 APP – DTC field definition . 9
9.4 APP – DTC functional unit definition. 9
9.5 APP – Negative response code (NRC). 10
9.6 APP – Communication profile (ComProfile) . 10
10 OSI-layers-related technical requirements overview .11
11 Application layer .12
11.1 AL – Diagnostic services overview .12
11.2 AL – CommunicationControl . 13
11.3 AL – ReadDataByIdentifier . 13
11.4 AL – ReadDtcInformation . 14
11.4.1 AL – General . 14
11.4.2 AL – Applicable ReadDtcInformation service subFunctions . . 14
11.5 AL – Application layer communication profile (ComProfile) . 14
12 Presentation layer .14
13 Session layer .14
13.1 SL – Service primitive interface parameter definition . 14
13.2 SL – S_Data.req, S_Data.ind, and S_Data.con service interface . 14
13.3 SL – Service primitive interface AL to SL parameter mapping . 15
13.4 SL – Session layer communication profile (ComProfile) . 15
14 Transport layer .15
14.1 TL – USDT service primitive interface parameter definition . 15
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ISO 11992-4:2023(E)
14.2 TL – T_Data.req, T_Data.ind, and T_Data.con service interface .15
14.3 TL – Service primitive interface SL to TL parameter mapping . 16
14.4 TL – Transport protocol . 16
14.5 TL – Transport layer communication profile (ComProfile) . 16
15 Network layer .16
15.1 NL – Service primitive interface parameter definition . 16
15.2 NL – N_Data.req, N_Data.ind, and N_Data.con service interface . 17
15.3 NL – Service primitive interface TL to NL parameter mapping . 17
15.4 NL – Network layer services . 17
15.5 NL – Network layer communication profile (ComProfile) . 17
15.6 NL – Diagnostic CAN identifier configuration . 18
15.7 NL – Dynamic network address assignment . 19
15.7.1 NL – General . 19
15.7.2 NL – Address assignment of TTN_1 and TTN_3 . 19
15.7.3 NL – Address assignment of TTN_2 and TTN_4 . 20
15.8 NL – Static network address assignment . 20
15.8.1 NL – General . 20
15.8.2 NL – Address assignment of gateway application, IVN_1, and IVN_2 .20
15.8.3 NL – Server address assignment of IVN_1 and IVN_2 .20
15.9 NL – Gateway N_PDU routing .20
15.9.1 NL – General . 20
15.9.2 NL – Network address translation . 21
15.10 NL – Diagnostic communication port (DCP) . 25
16 Data link layer .25
16.1 DL – Service primitive interface parameter definition . 25
16.2 DL – L_Data.req, L_Data.ind, and L_Data.con service interface . 25
16.3 DL – Service primitive interface NL to DL parameter mapping . 26
16.4 DL – CAN data frame . 26
16.5 DL – Data link layer communication profile (ComProfile). 26
17 Physical layer .26
Annex A (normative) Network address assignment .28
Bibliography .30
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ISO 11992-4:2023(E)
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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
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. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see ww.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 31,
Data communication.
This third edition cancels and replaces the second edition (ISO 11992-4:2014), which has been
technically revised.
The main changes are as follows:
— introduction of requirement structure with numbering and name;
— introduction of application requirements;
— introduction of OSI layers related requirements;
— clarification on gateway network address translation (deleted subnet addressing subclause).
A list of all parts in the ISO 11992 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
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ISO 11992-4:2023(E)
Introduction
The ISO 11992 series specifies the interchange of digital information between road vehicles with a
maximum authorised total mass greater than 3 500 kg, and towed vehicles, including communication
between towed vehicles in terms of parameters and requirements of the lower OSI layers (physical and
data link layer) of the electrical connection used to connect the electrical and electronic systems.
This document is structured according to the Open Systems Interconnection (OSI) Basic Reference
Model, in accordance with ISO/IEC 7498-1 and ISO/IEC 10731, which structures communication
systems into seven layers. When mapped on this model, the application layer protocol and data link
layer framework requirements specified/referenced in the ISO 11992 series are structured according
to Figure 1.
Figure 1 illustrates a simplified communication framework:
— vehicle normal communication framework,
— vehicle diagnostic communication framework,
— vehicle-specific use case framework, and
— vehicle lower-layers framework.
The vehicle normal communication framework is composed of ISO 11992-2 and ISO 11992-3.
The vehicle diagnostic communication framework is composed of ISO 14229-1, ISO 14229-2, ISO 14229-3
and this document.
The vehicle-specific use case framework is composed of this document, ISO 22901-1 or vehicle
manufacturer-specific diagnostic data definition.
Figure 1 — ISO documents reference according to the OSI model
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INTERNATIONAL STANDARD ISO 11992-4:2023(E)
Road vehicles — Interchange of digital information
on electrical connections between towing and towed
vehicles —
Part 4:
Diagnostic communication
1 Scope
This document specifies diagnostic application requirements and OSI-layer related communication
profiles to ensure the interchange of digital information between towing and towed vehicles with a
maximum authorized total mass greater than 3 500 kg.
The conformance and interoperability test plans are not part of this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 11992-1, Road vehicles — Interchange of digital information on electrical connections between towing
and towed vehicles — Part 1: Physical and data-link layers
ISO 11992-2:2023, Road vehicles — Interchange of digital information on electrical connections between
towing and towed vehicles — Part 2: Application layer for brakes and running gear
ISO 11992-3:2021, Road vehicles — Interchange of digital information on electrical connections between
towing and towed vehicles — Part 3: Application layer for equipment other than brakes and running gear
ISO 14229-1, Road vehicles — Unified diagnostic services (UDS) — Part 1: Application layer
ISO 14229-2, Road vehicles — Unified diagnostic services (UDS) — Part 2: Session layer services
ISO 14229-3, Road vehicles — Unified diagnostic services (UDS) — Part 3: Unified diagnostic services on
CAN implementation (UDSonCAN)
ISO 15765-2, Road vehicles — Diagnostic communication over Controller Area Network (DoCAN) — Part 2:
Transport protocol and network layer services
ISO 15765-5, Road vehicles — Diagnostic communication over Controller Area Network (DoCAN) — Part 5:
Specification for an in-vehicle network connected to the diagnostic link connector
SAE J1939-21, Data Link Layer
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 11992-1, ISO 14229-1,
ISO 14229-2, ISO 14229-3 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
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ISO 11992-4:2023(E)
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
mandatory
M
keyword indicating an item that is required to be implemented as defined in this document to claim
compliance with this document
[SOURCE: ISO/IEC 14776-113:2002, 3.3.3, modified — The word “standard” has been replaced by
“document”.]
4 Symbols and abbreviated terms
4.1 Symbols
— empty table cell or feature undefined
4.2 Abbreviated terms
CEFF classical extended frame format
ComProfile communication profile
Cvt convention
DA destination address (see SAE J1939-21)
DP data page (see SAE J1939-21)
ECU electronic control unit
EDP extended data page (see SAE J1939-21)
GW gateway
M mandatory
NAT network address translation
P priority (see SAE J1939-21)
PDU protocol data unit
PF PDU format (see SAE J1939-21)
PGN parameter group number (see SAE J1939-21)
PS PDU specific: destination address or group extension (see SAE J1939-21)
USDT unacknowledged segmented data transfer
VIN vehicle identification number
5 Conventions
This document is based on the conventions used in ISO 14229-1 and the underlying OSI Service
Conventions (ISO/IEC 10731) as they apply for diagnostic services.
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ISO 11992-4:2023(E)
These conventions specify the interactions between the service user and the service provider. The
information is passed between the service user and the service provider by the service primitives,
which can convey parameters.
6 Vehicle network architecture
Figure 2 shows a possible road train configuration.
Key
1 towing vehicle 0
2 towed vehicle 1
3 towed vehicle 2 (dolly)
4 towed vehicle 3
Figure 2 — Example of a possible road train configuration
Figure 3 shows the vehicle network architecture. The external client 0.0 (external test equipment)
connects to the vehicle's diagnostic connector.
The gateway 0.0 of vehicle 0 connects the in-vehicle network(s) (Figure 3, key a), which is (are)
comprised of, e.g. network(s) Figure 3, keys 4 and 5 with an internal client 0.0 and servers (0.1 to 0.A). It
also connects vehicle 0 to the gateway 1.0 of vehicle 1 with a logical communication link Figure 3, key 2
based on ISO 11992-2 and Figure 3, key 3 based on ISO 11992-3.
Gateway 1.0 of vehicle 1 connects the in-vehicle network(s) (Figure 3, key a), which is (are) comprised
of, e.g. network(s) Figure 3, keys 4 and 5 with servers (1.1 to 1.B). It also connects vehicle 1 to the
gateway 2.0 (3.0, 4.0, 5.0) of vehicle 2 (3, 4, 5) with a logical communication link Figure 3, key 2 based
on ISO 11992-2 and Figure 3, key 3 based on ISO 11992-3.
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ISO 11992-4:2023(E)
Key
1 external diagnostic connection: ISO 11898 CAN, ISO 13400 Ethernet
2 ISO 11992-2 messages on ISO 11992-1 communication link
3 ISO 11992-3 messages on ISO 11992-1 communication link
4 ISO 11992-2 messages on ISO 11992-1 communication link
5 ISO 11992-3 messages on ISO 11992-1 communication link
a
In-vehicle network(s): e.g. ISO 11992-2, ISO 11992-3, the ISO 17987 series, the ISO 20794 series, ISO/IEC/
IEEE 8802.3, discrete connection.
Figure 3 — Logical vehicle network architecture
The diagnostic communication addressing scheme is initiated from the client (external or internal) to
one (physical: point to point addressing) or multiple (functional: one to many addressing) servers.
There is no mechanism specified in this document to synchronise multiple clients.
7 Non OSI-layer-related technical requirements overview
Tables 1 and 2 provide an overview about non OSI-layer-related technical requirements and associated
requirement numbers.
Table 1 — Abstract service primitive interface-related technical requirements overview
ASP#.REQ# Technical requirement title
0 Abstract service primitive interface (ASP) definition
0.1 ASP – A_Data.req, A_Data.ind, and A_Data.con service primitive interface
0.2 ASP – Abstract service primitive interface parameters
0.3 ASP – Applicable A_Data service interface parameters
0.4 ASP – Data type definitions
0.5 ASP – Mtype, message type
0.6 ASP – TAtype, target address type
0.7 ASP – AE, address extension
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ISO 11992-4:2023(E)
TTabablele 1 1 ((ccoonnttiinnueuedd))
ASP#.REQ# Technical requirement title
0.8 ASP – TA, target address
0.9 ASP – SA, source address
0.10 ASP – Length, length of PDU
0.11 ASP – PDU, protocol data unit
0.12 ASP – Result, result
Table 2 — Application-related technical requirements overview
APP#.REQ# Technical requirement title
8 Application
8.1 APP – Data identifier (DID) definition
8.2 APP – DTC field definition
8.3 APP – DTC functional unit definition
8.4 APP – Negative response code (NRC)
8.5 APP – Communication profile (ComProfile)
8 Abstract service primitive interface (ASP) definition
8.1 ASP – A_Data.req, A_Data.ind, and A_Data.con service primitive interface
The definitions in this document follow the abstract service primitive interface definition in the
ISO 14229-1 specification.
REQ 0.1 ASP – A_Data.req, A_Data.ind, and A_Data.con service primitive interface
The A_Data.req, A_Data.ind, and A_Data.con abstract service primitive interface shall be implemented
as specified in ISO 14229-1.
The service interface defines the service and parameter mapping to the application and the lower OSI
layers.
Figure 4 shows the A_Data.req (request), A_Data.ind (indication) and A_Data.con (confirmation)
service interface.
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ISO 11992-4:2023(E)
Key
t time
1 service access point
2 read back from N-layer service provider
Figure 4 — A_Data.req, A_Data.ind, and A_Data.con service interface
8.2 ASP – Service interface parameters
8.2.1 General
The abstract service primitive interface parameters are used by the management of the OSI-layers.
REQ 0.2 ASP – ISO 14229-1 service interface parameters
The service primitive interface parameters shall be implemented as specified in ISO 14229-1.

REQ 0.3 ASP – Applicable A_Data service interface parameters
The A_Data abstract service primitives shall use the service primitive parameters as specified in Table 3.
Table 3 — A_Data abstract service primitive parameters
ASP parameter .req .ind .con Description
A_Mtype
X X — message type [RDiagMixAddr]: remote diagnostics mixed address-
ing
A_AI[TAtype]
X X X target address type [functional, physical]
A_AI[SA]
X X X source address
A_AI[TA]
X X X target address
A_AI[AE]
X X X address extension
A_Length
X X — length of PDU
A_Data
X X — A_PDU data
A_Result
— X X result of service primitive interface execution
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ISO 11992-4:2023(E)
8.2.2 ASP – Data type definitions
REQ 0.4 ASP – Data type definitions
The data types shall be in accordance to:
— Enum: 8-bit enumeration,
— Unsigned Byte: 8-bit unsigned numeric value,
— Unsigned Word: 16-bit unsigned numeric value,
— Unsigned Long: 32-bit unsigned numeric value,
— Byte Array: sequence of 8-bit aligned data,
— Bit String: 8-bit binary coded.
8.2.3 ASP – Mtype, message type
REQ 0.5 ASP – Mtype, message type
The Mtype parameter shall be of data type Enum and shall be used to identify the message type and range
of address information included in a service call.
Range: [RDiagMixAddr]
8.2.4 ASP – TAtype, target address type
REQ 0.6 ASP – TAtype, target address type
The TAtype parameter shall be of data type Enum and shall be used to identify the target address type
to be used with the request address.
Range: [physical, functional]
8.2.5 ASP – AE, address extension
REQ 0.7 ASP – AE, address ext
...

ISO/TC 22/SC 31 N
Date: 2022-11-232023-02
ISO/PROOF 11992-4:2022(E)
ISO/TC 22/SC 31/WG 4
Secretariat: DIN
Road vehicles — Interchange of digital information on electrical connections
between towing and towed vehicles — Part 4: Diagnostic communication
Véhicules routiers — Échange d'informations numériques sur les connexions électriques
entre véhicules tracteurs et véhicules tractés — Partie 4: Communication de diagnostic

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ISO/DIS 11992-4:20222023(E)
Copyright notice
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the reproduction of working drafts or committee drafts in any form for use by participants in the
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Violators may be prosecuted.
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ISO/DIS 11992-4:20222023(E)
Contents Page
Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 2
4.1 Symbols . 2
4.2 Abbreviated terms . 2
5 Conventions . 3
6 Vehicle network architecture . 3
7 Non OSI-layer-related technical requirements overview . 4
8 Service primitive interface (SI) definition . 5
8.1 SI – A_Data.req, A_Data.ind, and A_Data.conf service primitive interface . 5
8.2 SI – Service interface parameters . 6
8.2.1 General .6
8.2.2 SIP – Data type definitions .7
8.2.3 SIP – Mtype, message type .7
8.2.4 SIP – TAtype, target address type .7
8.2.5 SIP – AE, address extension .7
8.2.6 SIP – TA, target address .7
8.2.7 SIP – SA, source address .8
8.2.8 SIP – Length, length of PDU .8
8.2.9 SIP – PDU, protocol data unit .8
8.2.10 SIP – Result, result .8
9 Application . 8
9.1 APP – Addressing of requested information . 8
9.2 APP – Data identifier (DID) definition . 8
9.3 APP – DTC field definition . 9
9.4 APP – DTC functional unit definition . 9
9.5 APP – Negative response code (NRC) . 10
9.6 APP – Communication profile (ComProfile) . 11
10 OSI-layers-related technical requirements overview . 11
11 Application layer . 13
11.1 AL – Diagnostic services overview . 13
11.2 AL – CommunicationControl . 14
11.3 AL – ReadDataByIdentifier . 14
11.4 AL – ReadDtcInformation . 15
11.4.1 AL – General . 15
11.4.2 AL – Applicable ReadDtcInformation service subFunctions . 15
11.5 AL – Application layer communication profile (ComProfile) . 15
12 Presentation layer . 15
13 Session layer . 15
13.1 SL – Service primitive interface parameter definition . 15
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ISO/DIS 11992-4:20222023(E)
13.2 SL – S_Data.req, S_Data.ind, and S_Data.conf service interface . 16
13.3 SL – Service primitive interface AL to SL parameter mapping . 16
13.4 SL – Session layer communication profile (ComProfile) . 16
14 Transport layer . 17
14.1 TL – USDT service primitive interface parameter definition . 17
14.2 TL – T_Data.req, T_Data.ind, and T_Data.conf service interface . 17
14.3 TL – Service primitive interface SL to TL parameter mapping . 17
14.4 TL – Transport protocol . 17
14.5 TL – Transport layer communication profile (ComProfile) . 18
15 Network layer . 18
15.1 NL – Service primitive interface parameter definition . 18
15.2 NL – N_Data.req, N_Data.ind, and N_Data.conf service interface. 18
15.3 NL – Service primitive interface TL to NL parameter mapping . 18
15.4 NL – Network layer services . 19
15.5 NL – Network layer communication profile (ComProfile) . 19
15.6 NL – Diagnostic CAN identifier configuration . 20
15.7 NL – Dynamic network address assignment . 21
15.7.1 NL – General . 21
15.7.2 NL – Address assignment of TTN_1 and TTN_3 . 21
15.7.3 NL – Address assignment of TTN_2 and TTN_4 . 21
15.8 NL – Static network address assignment . 22
15.8.1 NL – General . 22
15.8.2 NL – Address assignment of gateway application, IVN_1, and IVN_2 . 22
15.8.3 NL – Server address assignment of IVN_1 and IVN_2 . 22
15.9 NL – Gateway N_PDU routing . 22
15.9.1 NL – General . 22
15.9.2 NL – Network address translation . 23
15.10 NL – Diagnostic communication port (DCP) . 26
16 Data link layer . 26
16.1 DL – Service primitive interface parameter definition . 26
16.2 DL – L_Data.req, L_Data.ind, and L_Data.conf service interface . 26
16.3 DL – Service primitive interface NL to DL parameter mapping . 27
16.4 DL – CAN data frame . 27
16.5 DL – Data link layer communication profile (ComProfile) . 27
17 Physical layer . 28
Annex A (normative) Network address assignment . 29
A.1 Towing and towed vehicle network address assignment. 29
A.2 In-vehicle network address assignment . 30
Bibliography . 31
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ISO/DIS 11992-4:20222023(E)
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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
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. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see ww.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 31,
Data communication.
This third edition cancels and replaces the second edition (ISO 11992-4:2014), which has been
technically revised.
The main changes are as follows:
— introduction of requirement structure with numbering and name;
— introduction of application requirements;
— introduction of OSI layers related requirements;
— clarification on gateway network address translation (deleted subnet addressing subclause);).
A list of all parts in the ISO 11992 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
© ISO 20222023 – All rights reserved v

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ISO/DIS 11992-4:20222023(E)
Introduction
The ISO 11992 series specifies the interchange of digital information between road vehicles with a
maximum authorised total mass greater than 3 500 kg, and towed vehicles, including communication
between towed vehicles in terms of parameters and requirements of the lower OSI layers (physical and
data link layer) of the electrical connection used to connect the electrical and electronic systems.
This document is structured according to the Open Systems Interconnection (OSI) Basic Reference
[2] [3]
Model, in accordance with ISO/IEC 7498-1 and ISO/IEC 10731 ,, which structures communication
systems into seven layers. When mapped on this model, the application layer protocol and data link
layer framework requirements specified/referenced in the ISO 11992 series are structured according to
Figure 1.
Figure 1 illustrates a simplified communication framework:
— vehicle normal communication framework,
— vehicle diagnostic communication framework,
— vehicle-specific use case framework, and
— vehicle lower-layers framework.
The vehicle normal communication framework is composed of ISO 11992-2 and ISO 11992-3.
The vehicle diagnostic communication framework is composed of ISO 14229-1, ISO 14229-2,
ISO 14229-3 and this document.
[4]
The vehicle-specific use case framework is composed of this document, ISO 22901-1 or vehicle
manufacturer-specific diagnostic data definition.

vi © ISO 20222023 – All rights reserved

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ISO/DIS 11992-4:20222023(E)

Figure 1 — ISO documents reference according to the OSI model
© ISO 20222023 – All rights reserved vii

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DRAFT INTERNATIONAL STANDARD ISO/DIS 11992-4:20222023(E)

Road vehicles — Interchange of digital information on
electrical connections between towing and towed vehicles —
Part 4: Diagnostic communication
1 Scope
This document specifies diagnostic application requirements and OSI-layer related communication
profiles to ensure the interchange of digital information between towing and towed vehicles with a
maximum authorized total mass greater than 3 500 kg.
The conformance and interoperability test plans are not part of this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 11992-1, Road vehicles — Interchange of digital information on electrical connections between
towing and towed vehicles — Part 1: Physical and data-link layers
1
ISO 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
ISO 11992-3:2021, Road vehicles — Interchange of digital information on electrical connections between
towing and towed vehicles — Part 3: Application layer for equipment other than brakes and running gear
ISO 14229-1, Road vehicles — Unified diagnostic services (UDS) — Part 1: Application layer
ISO 14229-2, Road vehicles — Unified diagnostic services (UDS) — Part 2: Session layer services
ISO 14229-3, Road vehicles — Unified diagnostic services (UDS) — Part 3: Unified diagnostic services on
CAN implementation (UDSonCAN)
ISO 15765-2, Road vehicles — Diagnostic communication over Controller Area Network (DoCAN) — Part
2: Transport protocol and network layer services
ISO 15765-5, Road vehicles — Diagnostic communication over Controller Area Network (DoCAN) — Part
5: Specification for an in-vehicle network connected to the diagnostic link connector
SAE J1939-21, Data Link Layer

1
UnderFourth edition under preparation. Stage at the time of publication: ISO/DISFDIS 11992-
2:20222023.
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ISO/DIS 11992-4:20222023(E)
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 11992-1, ISO 14229-1,
ISO 14229-2, ISO 14229-3 and the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp
— IEC Electropedia: available at https://www.electropedia.org/
3.1
diagnostic gateway
node in a network that is physically connected to two (or more) networks and has the ability to transfer
diagnostic messages between the networks
3.2
mandatory
M
keyword indicating an item that is required to be implemented as defined in this document to claim
compliance with this document
[SOURCE: ISO/IEC 14776-113:2002, 3.3.3, modified — The word “standard” has been replaced by
“document”.]
3.3
user optional
U
keyword indicating that the referenced item is not required to claim compliance with this document
Note 1 to entry: Implementation of an optional item should be as defined in this document.
[SOURCE: ISO/IEC 15205:2000, 2.1.23, modified — The wording “keyword indicating that” has been
added; the word “standard” has been replaced by “document”; the last sentence in the definition has
been moved to Note 1 to entry.]
94 Symbols and abbreviated terms
9.14.1 Symbols
— empty table cell or feature undefined
9.24.2 Abbreviated terms
CEFF Classical Extended Frame Formatclassical extended frame format
ComProfile communication profile
Cvt convention
DA destination address (see SAE J1939-21)
DP data page (see SAE J1939-21)
ECU electronic control unit
EDP extended data page (see SAE J1939-21)
GW gateway
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ISO/DIS 11992-4:20222023(E)
M mandatory
NAT network address translation
P priority (see SAE J1939-21)
PDU protocol data unit
PF PDU format (see SAE J1939-21)
PGN parameter group number (see SAE J1939-21)
PS PDU specific: destination address or group extension (see SAE J1939-21)
USDT unacknowledged segmented data transfer
VIN vehicle identification number
105 Conventions
This document is based on the conventions used in ISO 14229-1 and the underlying OSI Service
Conventions (ISO/IEC 10731:1994) as they apply for diagnostic services.
These conventions specify the interactions between the service user and the service provider. The
information is passed between the service user and the service provider by the service primitives,
which can convey parameters.
116 Vehicle network architecture
Figure 2 shows a possible road train configuration.


Key
1 towing vehicle 0
2 towed vehicle 1
3 towed vehicle 2 (dolly)
4 towed vehicle 3
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ISO/DIS 11992-4:20222023(E)
Figure 2 — Example of a possible road train configuration
Figure 3 shows the vehicle network architecture. The external client 0.0 (external test equipment)
connects to the vehicle's diagnostic connector.
The gateway 0.0 of vehicle 0 connects the in-vehicle network(s) (Figure 3, key a), which is (are)
comprised of, e.g. network(s) Figure 3, keys 4 and 5 with an internal client 0.0 and servers (0.1 to 0.A).
It also connects vehicle 0 to the gateway 1.0 of vehicle 1 with a logical communication link Figure 3, key
2 based on ISO 11992-2 and Figure 3, key 3 based on ISO 11992-3.
Gateway 1.0 of vehicle 1 connects the in-vehicle network(s) (Figure 3, key a), which is (are) comprised
of, e.g.,. network(s) Figure 3, keys 4 and 5 with servers (1.1 to 1.B). It also connects vehicle 1 to the
gateway 2.0 (3.0, 4.0, 5.0) of vehicle 2 (3, 4, 5) with a logical communication link Figure 3, key 2 based
on ISO 11992-2 and Figure 3, key 3 based on ISO 11992-3.

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ISO/DIS 11992-4:20222023(E)

Key
1 external diagnostic connection: ISO 11898 CAN, ISO 13400 Ethernet
2 ISO 11992-2 messages on ISO 11992-1 communication link
3 ISO 11992-3 messages on ISO 11992-1 communication link
4 ISO 11992-2 messages on ISO 11992-1 communication link
5 ISO 11992-3 messages on ISO 11992-1 communication link
a
In-vehicle network(s): e.g. ISO 11992-2, ISO 11992-3, the ISO 17987 series, the ISO 20794 series, ISO/IEC/IEEE 8802.3,
discrete connection.
Figure 3 — Logical vehicle network architecture
The diagnostic communication addressing scheme is initiated from the client (external or internal) to
one (physical: point to point addressing) or multiple (functional: one to many addressing) servers.
There is no mechanism specified in this document to synchronise multiple clients.
127 Non OSI-layer-related technical requirements overview
TableTables 1 providesand 2 provide an overview about non OSI-layer-related technical requirements
and associated requirement numbers.
Table 1 — Abstract service primitive interface-related technical requirements overview
ASP#.REQ# Technical requirement title
0 Abstract service primitive interface (ASP) definition
0.1  ASP – A_Data.req, A_Data.ind, and A_Data.conf service primitive interface
0.2  ASP – Abstract service primitive interface parameters
0.3  ASP – Applicable A_Data service interface parameters
0.4  ASP – Data type definitions
0.5  ASP – Mtype, message type
0.6  ASP – TAtype, target address type
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ISO/DIS 11992-4:20222023(E)
ASP#.REQ# Technical requirement title
0.7  ASP – AE, address extension
0.8  ASP – TA, target address
0.9  ASP – SA, source address
0.10  ASP – Length, length of PDU
0.11  ASP – PDU, protocol data unit
0.12  ASP – Result, result
Table 2 — Application-related technical requirements overview
APP#.REQ# Technical requirement title
8 Application
8.1  APP – Data identifier (DID) definition
8.2  APP – DTC field definition
8.3  APP – DTC functional unit definition
8.4  APP – Negative response code (NRC)
8.5  APP – Communication profile (ComProfile)
138 Abstract service primitive interface (ASP) definition
13.18.1 ASP – A_Data.req, A_Data.ind, and A_Data.conf service primitive interface
The definitions in this document follow the abstract service primitive interface definition in the
ISO 14229-1 specification.
REQ 0.1 ASP – A_Data.req, A_Data.ind, and A_Data.conf service primitive interface
The A_Data.req, A_Data.ind, and A_Data.conf abstract service primitive interface shall be
implemented as specified in ISO 14229-1.
The service interface defines the service and parameter mapping to the application and the lower OSI
layers.
Figure 4 shows the A_Data.req (request), A_Data.ind (indication) and A_Data.conf
(confirmation) service interface.
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ISO/DIS 11992-4:20222023(E)


Key
t time
1 service access point
2 read back from N-layer service provider
Figure 4 — A_Data.req, A_Data.ind, and A_Data.conf service interface
13.28.2 ASP – Service interface parameters
13.2.18.2.1 General
The abstract service primitive interface parameters are used by the management of the OSI-layers.
REQ 0.2 ASP – ISO 14229-1 service interface parameters
The service primitive interface parameters shall be implemented as specified in ISO 14229-1.

REQ 0.3 ASP – Applicable A_Data service interface parameters
The A_Data abstract service primitives shall use the service primitive parameters as specified in Table 23.
Table 23 — A_Data abstract service primitive parameters
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ISO/DIS 11992-4:20222023(E)
ASP parameter .req .ind .conf Description
A_Mtype X X — message type [RDiagMixAddr]: remote diagnostics mixed
addressing
A_AI[TAtype] X X X target address type [functional, physical]
A_AI[SA]
X X X source address
A_AI[TA]
X X X target address
A_AI[AE] X X X address extension
A_Length X X — length of PDU
A_Data X X — A_PDU data
A_Result — X X result of service primitive interface execution
13.2.28.2.2 ASP – Data type definitions
REQ 0.4 ASP – Data type definitions
The data types shall be in accordance to:
— Enum: 8-bit enumeration,
— Unsigned Byte: 8-bit unsigned numeric value,
— Unsigned Word: 16-bit unsigned numeric value,
— Unsigned Long: 32-bit unsigned numeric value,
— Byte Array: sequence of 8-bit aligned data,
— Bit String: 8-bit binary coded.
13.2.38.2.3 ASP – Mtype, message type
REQ 0.5 ASP – Mtype, message type
The Mtype parameter shall be of data type Enum and shall be used to identify the message type and range of
address information included in a service call.
Range: [RDiagMixAddr]
13.2.48.2.4 ASP – TAtype, target address type
REQ 0.6 ASP – TAtype, target address type
The TAtype parameter shall be of data type Enum and shall be used to identify the target address type to be
used with the request address.
Range: [physical]
13.2.58.2.5 ASP – AE, address extension
REQ 0.7 ASP – AE, address extension
The AE parameter shall be of data type Unsigned Word and shall be used to extend the available address
range for large networks and to encode both, sending and receiving network layer entities of sub-networks other
than the local network where the communication takes place. AE is only part of the addressing information if
Mtype is set to remote diagnostics (RDiagMixAddr).
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ISO/DIS 11992-4:20222023(E)
Range: [0000 to FFFF ]
16 16
13.2.68.2.6 ASP – TA, target address
REQ 0.8 ASP – TA, target address
The TA parameter shall be of data type Unsigned Word and shall contain the target address of the node.
Range: [0000 to FFFF ]
16 16
13.2.78.2.7 ASP – SA, source address
REQ 0.9 ASP – SA, source address
The SA parameter shall be of data type Unsigned Word and shall contain the source address of the node.
Range: [0000 to FFFF ]
16 16
13.2.88.2.8 ASP – Length, length of PDU
REQ 0.10 ASP – Length, length of PDU
The Length paramet
...

INTERNATIONAL ISO
STANDARD 11992-4
Third edition
Road vehicles — Interchange of digital
information on electrical connections
between towing and towed vehicles —
Part 4:
Diagnostic communication
Véhicules routiers — Échange d'informations numériques sur
les connexions électriques entre véhicules tracteurs et véhicules
tractés —
Partie 4: Communication de diagnostic
PROOF/ÉPREUVE
Reference number
ISO 11992-4:2023(E)
© ISO 2023

---------------------- Page: 1 ----------------------
ISO 11992-4:2023(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2023
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on
the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below
or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii
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ISO 11992-4:2023(E)
Contents Page
Foreword .v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms.2
4.1 Symbols . 2
4.2 Abbreviated terms . 2
5 Conventions . 3
6 Vehicle network architecture .3
7 Non OSI-layer-related technical requirements overview . 4
8 Abstract service primitive interface (ASP) definition . 5
8.1 ASP – A_Data.req, A_Data.ind, and A_Data.conf service primitive interface . 5
8.2 ASP – Service interface parameters . 6
8.2.1 General . 6
8.2.2 ASP – Data type definitions . 7
8.2.3 ASP – Mtype, message type . 7
8.2.4 ASP – TAtype, target address type . 7
8.2.5 ASP – AE, address extension . 7
8.2.6 ASP – TA, target address . 7
8.2.7 ASP – SA, source address . 7
8.2.8 ASP – Length, length of PDU. 8
8.2.9 ASP – PDU, protocol data unit . 8
8.2.10 ASP – Result, result . 8
9 Application .8
9.1 APP – Addressing of requested information . 8
9.2 APP – Data identifier (DID) definition . 8
9.3 APP – DTC field definition . 9
9.4 APP – DTC functional unit definition. 9
9.5 APP – Negative response code (NRC). 10
9.6 APP – Communication profile (ComProfile) . 10
10 OSI-layers-related technical requirements overview .11
11 Application layer .12
11.1 AL – Diagnostic services overview .12
11.2 AL – CommunicationControl . 13
11.3 AL – ReadDataByIdentifier . 13
11.4 AL – ReadDtcInformation . 14
11.4.1 AL – General . 14
11.4.2 AL – Applicable ReadDtcInformation service subFunctions . . 14
11.5 AL – Application layer communication profile (ComProfile) . 14
12 Presentation layer .14
13 Session layer .14
13.1 SL – Service primitive interface parameter definition . 14
13.2 SL – S_Data.req, S_Data.ind, and S_Data.conf service interface . 14
13.3 SL – Service primitive interface AL to SL parameter mapping . 15
13.4 SL – Session layer communication profile (ComProfile) . 15
14 Transport layer .15
14.1 TL – USDT service primitive interface parameter definition . 15
iii
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ISO 11992-4:2023(E)
14.2 TL – T_Data.req, T_Data.ind, and T_Data.conf service interface .15
14.3 TL – Service primitive interface SL to TL parameter mapping . 16
14.4 TL – Transport protocol . 16
14.5 TL – Transport layer communication profile (ComProfile) . 16
15 Network layer .16
15.1 NL – Service primitive interface parameter definition . 16
15.2 NL – N_Data.req, N_Data.ind, and N_Data.conf service interface. 17
15.3 NL – Service primitive interface TL to NL parameter mapping . 17
15.4 NL – Network layer services . 17
15.5 NL – Network layer communication profile (ComProfile) . 17
15.6 NL – Diagnostic CAN identifier configuration . 18
15.7 NL – Dynamic network address assignment . 19
15.7.1 NL – General . 19
15.7.2 NL – Address assignment of TTN_1 and TTN_3 . 19
15.7.3 NL – Address assignment of TTN_2 and TTN_4 . 20
15.8 NL – Static network address assignment . 20
15.8.1 NL – General . 20
15.8.2 NL – Address assignment of gateway application, IVN_1, and IVN_2 .20
15.8.3 NL – Server address assignment of IVN_1 and IVN_2 .20
15.9 NL – Gateway N_PDU routing .20
15.9.1 NL – General . 20
15.9.2 NL – Network address translation . 21
15.10 NL – Diagnostic communication port (DCP) . 25
16 Data link layer .25
16.1 DL – Service primitive interface parameter definition . 25
16.2 DL – L_Data.req, L_Data.ind, and L_Data.conf service interface . 25
16.3 DL – Service primitive interface NL to DL parameter mapping . 26
16.4 DL – CAN data frame . 26
16.5 DL – Data link layer communication profile (ComProfile). 26
17 Physical layer .26
Annex A (normative) Network address assignment .28
Bibliography .30
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ISO 11992-4:2023(E)
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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
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. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see ww.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html.
This document was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 31,
Data communication.
This third edition cancels and replaces the second edition (ISO 11992-4:2014), which has been
technically revised.
The main changes are as follows:
— introduction of requirement structure with numbering and name;
— introduction of application requirements;
— introduction of OSI layers related requirements;
— clarification on gateway network address translation (deleted subnet addressing subclause).
A list of all parts in the ISO 11992 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www.iso.org/members.html.
v
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ISO 11992-4:2023(E)
Introduction
The ISO 11992 series specifies the interchange of digital information between road vehicles with a
maximum authorised total mass greater than 3 500 kg, and towed vehicles, including communication
between towed vehicles in terms of parameters and requirements of the lower OSI layers (physical and
data link layer) of the electrical connection used to connect the electrical and electronic systems.
This document is structured according to the Open Systems Interconnection (OSI) Basic Reference
Model, in accordance with ISO/IEC 7498-1 and ISO/IEC 10731, which structures communication
systems into seven layers. When mapped on this model, the application layer protocol and data link
layer framework requirements specified/referenced in the ISO 11992 series are structured according
to Figure 1.
Figure 1 illustrates a simplified communication framework:
— vehicle normal communication framework,
— vehicle diagnostic communication framework,
— vehicle-specific use case framework, and
— vehicle lower-layers framework.
The vehicle normal communication framework is composed of ISO 11992-2 and ISO 11992-3.
The vehicle diagnostic communication framework is composed of ISO 14229-1, ISO 14229-2, ISO 14229-3
and this document.
The vehicle-specific use case framework is composed of this document, ISO 22901-1 or vehicle
manufacturer-specific diagnostic data definition.
Figure 1 — ISO documents reference according to the OSI model
vi
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INTERNATIONAL STANDARD ISO 11992-4:2023(E)
Road vehicles — Interchange of digital information
on electrical connections between towing and towed
vehicles —
Part 4:
Diagnostic communication
1 Scope
This document specifies diagnostic application requirements and OSI-layer related communication
profiles to ensure the interchange of digital information between towing and towed vehicles with a
maximum authorized total mass greater than 3 500 kg.
The conformance and interoperability test plans are not part of this document.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 11992-1, Road vehicles — Interchange of digital information on electrical connections between towing
and towed vehicles — Part 1: Physical and data-link layers
1)
ISO 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
ISO 11992-3:2021, Road vehicles — Interchange of digital information on electrical connections between
towing and towed vehicles — Part 3: Application layer for equipment other than brakes and running gear
ISO 14229-1, Road vehicles — Unified diagnostic services (UDS) — Part 1: Application layer
ISO 14229-2, Road vehicles — Unified diagnostic services (UDS) — Part 2: Session layer services
ISO 14229-3, Road vehicles — Unified diagnostic services (UDS) — Part 3: Unified diagnostic services on
CAN implementation (UDSonCAN)
ISO 15765-2, Road vehicles — Diagnostic communication over Controller Area Network (DoCAN) — Part 2:
Transport protocol and network layer services
ISO 15765-5, Road vehicles — Diagnostic communication over Controller Area Network (DoCAN) — Part 5:
Specification for an in-vehicle network connected to the diagnostic link connector
SAE J1939-21, Data Link Layer
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 11992-1, ISO 14229-1,
ISO 14229-2, ISO 14229-3 and the following apply.
1) Fourth edition under preparation. Stage at the time of publication: ISO/FDIS 11992-2:2023.
1
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ISO 11992-4:2023(E)
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
mandatory
M
keyword indicating an item that is required to be implemented as defined in this document to claim
compliance with this document
[SOURCE: ISO/IEC 14776-113:2002, 3.3.3, modified — The word “standard” has been replaced by
“document”.]
4 Symbols and abbreviated terms
4.1 Symbols
— empty table cell or feature undefined
4.2 Abbreviated terms
CEFF classical extended frame format
ComProfile communication profile
Cvt convention
DA destination address (see SAE J1939-21)
DP data page (see SAE J1939-21)
ECU electronic control unit
EDP extended data page (see SAE J1939-21)
GW gateway
M mandatory
NAT network address translation
P priority (see SAE J1939-21)
PDU protocol data unit
PF PDU format (see SAE J1939-21)
PGN parameter group number (see SAE J1939-21)
PS PDU specific: destination address or group extension (see SAE J1939-21)
USDT unacknowledged segmented data transfer
VIN vehicle identification number
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ISO 11992-4:2023(E)
5 Conventions
This document is based on the conventions used in ISO 14229-1 and the underlying OSI Service
Conventions (ISO/IEC 10731) as they apply for diagnostic services.
These conventions specify the interactions between the service user and the service provider. The
information is passed between the service user and the service provider by the service primitives,
which can convey parameters.
6 Vehicle network architecture
Figure 2 shows a possible road train configuration.
Key
1 towing vehicle 0
2 towed vehicle 1
3 towed vehicle 2 (dolly)
4 towed vehicle 3
Figure 2 — Example of a possible road train configuration
Figure 3 shows the vehicle network architecture. The external client 0.0 (external test equipment)
connects to the vehicle's diagnostic connector.
The gateway 0.0 of vehicle 0 connects the in-vehicle network(s) (Figure 3, key a), which is (are)
comprised of, e.g. network(s) Figure 3, keys 4 and 5 with an internal client 0.0 and servers (0.1 to 0.A). It
also connects vehicle 0 to the gateway 1.0 of vehicle 1 with a logical communication link Figure 3, key 2
based on ISO 11992-2 and Figure 3, key 3 based on ISO 11992-3.
Gateway 1.0 of vehicle 1 connects the in-vehicle network(s) (Figure 3, key a), which is (are) comprised
of, e.g. network(s) Figure 3, keys 4 and 5 with servers (1.1 to 1.B). It also connects vehicle 1 to the
gateway 2.0 (3.0, 4.0, 5.0) of vehicle 2 (3, 4, 5) with a logical communication link Figure 3, key 2 based
on ISO 11992-2 and Figure 3, key 3 based on ISO 11992-3.
3
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ISO 11992-4:2023(E)
Key
1 external diagnostic connection: ISO 11898 CAN, ISO 13400 Ethernet
2 ISO 11992-2 messages on ISO 11992-1 communication link
3 ISO 11992-3 messages on ISO 11992-1 communication link
4 ISO 11992-2 messages on ISO 11992-1 communication link
5 ISO 11992-3 messages on ISO 11992-1 communication link
a
In-vehicle network(s): e.g. ISO 11992-2, ISO 11992-3, the ISO 17987 series, the ISO 20794 series, ISO/IEC/
IEEE 8802.3, discrete connection.
Figure 3 — Logical vehicle network architecture
The diagnostic communication addressing scheme is initiated from the client (external or internal) to
one (physical: point to point addressing) or multiple (functional: one to many addressing) servers.
There is no mechanism specified in this document to synchronise multiple clients.
7 Non OSI-layer-related technical requirements overview
Tables 1 and 2 provide an overview about non OSI-layer-related technical requirements and associated
requirement numbers.
Table 1 — Abstract service primitive interface-related technical requirements overview
ASP#.REQ# Technical requirement title
0 Abstract service primitive interface (ASP) definition
0.1 ASP – A_Data.req, A_Data.ind, and A_Data.conf service primitive interface
0.2 ASP – Abstract service primitive interface parameters
0.3 ASP – Applicable A_Data service interface parameters
0.4 ASP – Data type definitions
0.5 ASP – Mtype, message type
0.6 ASP – TAtype, target address type
0.7 ASP – AE, address extension
4
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ISO 11992-4:2023(E)
TTabablele 1 1 ((ccoonnttiinnueuedd))
ASP#.REQ# Technical requirement title
0.8 ASP – TA, target address
0.9 ASP – SA, source address
0.10 ASP – Length, length of PDU
0.11 ASP – PDU, protocol data unit
0.12 ASP – Result, result
Table 2 — Application-related technical requirements overview
APP#.REQ# Technical requirement title
8 Application
8.1 APP – Data identifier (DID) definition
8.2 APP – DTC field definition
8.3 APP – DTC functional unit definition
8.4 APP – Negative response code (NRC)
8.5 APP – Communication profile (ComProfile)
8 Abstract service primitive interface (ASP) definition
8.1 ASP – A_Data.req, A_Data.ind, and A_Data.conf service primitive interface
The definitions in this document follow the abstract service primitive interface definition in the
ISO 14229-1 specification.
REQ 0.1 ASP – A_Data.req, A_Data.ind, and A_Data.conf service primitive interface
The A_Data.req, A_Data.ind, and A_Data.conf abstract service primitive interface shall be implemented
as specified in ISO 14229-1.
The service interface defines the service and parameter mapping to the application and the lower OSI
layers.
Figure 4 shows the A_Data.req (request), A_Data.ind (indication) and A_Data.conf (confirmation)
service interface.
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ISO 11992-4:2023(E)
Key
t time
1 service access point
2 read back from N-layer service provider
Figure 4 — A_Data.req, A_Data.ind, and A_Data.conf service interface
8.2 ASP – Service interface parameters
8.2.1 General
The abstract service primitive interface parameters are used by the management of the OSI-layers.
REQ 0.2 ASP – ISO 14229-1 service interface parameters
The service primitive interface parameters shall be implemented as specified in ISO 14229-1.

REQ 0.3 ASP – Applicable A_Data service interface parameters
The A_Data abstract service primitives shall use the service primitive parameters as specified in Table 3.
Table 3 — A_Data abstract service primitive parameters
ASP parameter .req .ind .conf Description
A_Mtype
X X — message type [RDiagMixAddr]: remote diagnostics mixed address-
ing
A_AI[TAtype]
X X X target address type [functional, physical]
A_AI[SA]
X X X source address
A_AI[TA]
X X X target address
A_AI[AE]
X X X address extension
A_Length
X X — length of PDU
A_Data
X X — A_PDU data
A_Result
— X X result of service primitive interface execution
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ISO 11992-4:2023(E)
8.2.2 ASP – Data type definitions
REQ 0.4 ASP – Data type definitions
The data types shall be in accordance to:
— Enum: 8-bit enumeration,
— Unsigned Byte: 8-bit unsigned numeric value,
— Unsigned Word: 16-bit unsigned numeric value,
— Unsigned Long: 32-bit unsigned numeric value,
— Byte Array: sequence of 8-bit aligned data,
— Bit String: 8-bit binary coded.
8.2.3 ASP – Mtype, message type
REQ 0.5 ASP – Mtype, message type
The Mtype parameter shall be of data type Enum and shall be used to identify the message type and range
of address information included in a service call.
Range: [RDiagMixAddr]
8.2.4 ASP – TAtype, target address type
REQ 0.6 ASP – TAtype, target a
...