Road vehicles -- Implementation of World-Wide Harmonized On-Board Diagnostics (WWH-OBD) communication requirements

ISO 27145-3:2012 defines the implementation of a subset of unified diagnostic services (UDS) specified in ISO 14229-1. The diagnostic services are used to communicate the diagnostic data defined in ISO 27145-2. The subset of unified diagnostic services derives from the requirements stated in the World-Wide Harmonized On-Board Diagnostic Global Technical Regulations (WWH-OBD GTR). The common message set defined in ISO 27145-3:2012 is independent of the underlying transport, network, data link and physical layer. ISO 27145-3:2012 does not specify any requirements for the in-vehicle network architecture. ISO 27145-3:2012 is compatible with ISO 14229-1 and includes provisions to support the data set of SAE J1979-DA and SAE J2012-DA WWH-OBD. ISO 27145-3:2012 is intended for use with ISO 27145-4, which is the entry point for the protocol initialization and is based on two different data links: · Diagnostic communication over Controller Area Network (DoCAN), ISO 15765‑1, ISO 15765‑2, ISO 15765‑4; · Diagnostic communication over Internet Protocol (DoIP), ISO 13400 (all parts). ISO 27145-3:2012 includes capabilities required to satisfy OBD regulations for multiple regions, vehicle types, model years, and engine types. Those regulations are not yet final for some regions and are expected to change in the future. ISO 27145-3:2012 does not attempt to interpret the regulations and does not include applicability of the included diagnostic services and data parameters for various vehicle applications. It is intended that users of ISO 27145-3:2012 verify the applicability of each of its clauses for a specific vehicle, engine, model year and region.

Véhicules routiers -- Mise en application des exigences de communication pour le diagnostic embarqué harmonisé à l'échelle mondiale (WWH-OBD)

General Information

Status
Published
Publication Date
13-Aug-2012
Current Stage
6060 - International Standard published
Start Date
26-Jun-2012
Completion Date
14-Aug-2012
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INTERNATIONAL ISO
STANDARD 27145-3
First edition
2012-08-15
Road vehicles — Implementation of
World-Wide Harmonized On-Board
Diagnostics (WWH-OBD) communication
requirements —
Part 3:
Common message dictionary
Véhicules routiers — Mise en application des exigences de
communication pour le diagnostic embarqué harmonisé à l’échelle
mondiale (WWH-OBD) —
Partie 3: Dictionnaire de messages communs
Reference number
ISO 27145-3:2012(E)
ISO 2012
---------------------- Page: 1 ----------------------
ISO 27145-3:2012(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2012

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,

electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO’s

member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved
---------------------- Page: 2 ----------------------
ISO 27145-3:2012(E)
Contents Page

Foreword ............................................................................................................................................................................iv

0 Introduction ........................................................................................................................................................... v

0.1 Overview ................................................................................................................................................................ v

0.2 SAE document reference concept .................................................................................................................. v

0.3 SAE digital annex revision procedure .......................................................................................................... vi

1 Scope ...................................................................................................................................................................... 1

2 Normative references ......................................................................................................................................... 1

3 Terms, definitions and abbreviated terms .................................................................................................... 2

3.1 Terms and definitions ......................................................................................................................................... 2

3.2 Abbreviated terms ............................................................................................................................................... 2

4 Conventions .......................................................................................................................................................... 3

5 Document overview ............................................................................................................................................ 3

6 Unified diagnostic services (UDS) applicable to WWH-OBD ................................................................... 4

6.1 General ................................................................................................................................................................... 4

6.2 UDS on WWH-OBD overview ........................................................................................................................... 5

6.3 Electronic control unit (ECU) response message length too long ........................................................ 5

6.4 Message byte order ............................................................................................................................................ 5

6.5 ReadDataByIdentifier (0x22) service .............................................................................................................. 6

6.6 ReadDTCInformation (0x19) service .............................................................................................................. 6

6.7 ClearDiagnosticInformation (0x14) service ................................................................................................14

6.8 RoutineControl (0x31) service .......................................................................................................................15

7 Application layer requirements .....................................................................................................................15

7.1 Application layer services ...............................................................................................................................15

7.2 Application layer protocol ...............................................................................................................................16

7.3 Addressing and timing requirements ..........................................................................................................16

8 Presentation layer requirements ...................................................................................................................25

9 Session layer requirements ............................................................................................................................25

Annex A (informative) WWH-OBD-related unified diagnostic service examples ............................................26

Bibliography .....................................................................................................................................................................44

© ISO 2012 – All rights reserved iii
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ISO 27145-3:2012(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.

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 27145-3 was prepared by Technical Committee ISO/TC 22, Road vehicles, Subcommittee SC 3, Electrical

and electronic equipment.

This first edition of ISO 27145-3 cancels and replaces ISO/PAS 27145-3:2006, which has been technically revised.

ISO 27145 consists of the following parts, under the general title Road vehicles — Implementation of World-

Wide Harmonized On-Board Diagnostics (WWH-OBD) communication requirements:
— Part 1: General information and use case definition
— Part 2: Common data dictionary
— Part 3: Common message dictionary
— Part 4: Connection between vehicle and test equipment
The following parts are under preparation:
— Part 6: External test equipment
iv © ISO 2012 – All rights reserved
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ISO 27145-3:2012(E)
0 Introduction
0.1 Overview

The ISO 27145 series includes the communication between the vehicle’s on-board diagnostics (OBD) systems

and external test equipment within the scope of the World-Wide Harmonized On-Board Diagnostics Global

Technical Regulations (WWH-OBD GTR).

It has been established in order to apply the unified diagnostic services (specified in ISO 14229-1) to

WWH-OBD systems.

The ISO 27145 series includes the communication between the vehicle’s WWH-OBD systems and external

(off-board) “generic” test equipment within the scope of the country-specific regulatory requirements.

To achieve this, it is based on the Open Systems Interconnection (OSI) Basic Reference Model specified

in ISO/IEC 7498-1 and ISO/IEC 10731, which structures communication systems into seven layers. When

mapped on this model, the services specified by ISO 27145 are divided into

— diagnostic services (layer 7), specified in ISO 27145-3 with reference to ISO 14229-1,

— presentation layer (layer 6), specified in ISO 27145-2 with reference to SAE J1930-DA, SAE J1939 Companion

Spreadsheet (SPNs), SAE J1939-73:2010, Appendix A (FMIs), SAE J1979-DA and SAE J2012-DA,

— session layer services (layer 5), specified in ISO 14229-2,

— transport layer services (layer 4), specified in ISO 27145-4 with reference to ISO 13400-2, ISO 15765-2

and ISO 15765-4,

— network layer services (layer 3), specified in ISO 27145-4 with reference to ISO 15765-4, ISO 15765-2

and ISO 13400-2,

— data link layer (layer 2), specified in ISO 27145-4 with reference to ISO 11898-1, ISO 11898-2, ISO 15765-4,

ISO 13400-3 and IEEE 802.3, and

— physical layer (layer 1), specified in ISO 27145-4 with reference to ISO 11898-1, ISO 11898-2, ISO 15765-4,

ISO 13400-3 and IEEE 802.3,
in accordance with Table 1.
Table 1 — WWH-OBD specification reference applicable to the OSI layers
Applicability OSI seven layer WWH-OBD document reference
Application (layer 7) ISO 14229-1, ISO 27145-3
ISO 27145-2,
Presentation (layer 6) SAE J1930-DA, SAE J1939 Companion Spreadsheet (SPNs),
SAE J1939-73:2010, Appendix A (FMIs), SAE J1979-DA, SAE J2012-DA
Seven layers
Session (layer 5) ISO 14229-2
according to
ISO/IEC 7498-1 and
Transport (layer 4)
ISO 15765-2 DoCAN, ISO 13400-2 DoIP
ISO/IEC 10731
ISO 15765-4 DoCAN TCP and IP
Network (layer 3)
ISO 27145-4
Data link (layer 2) ISO 11898-1 CAN DLL,
ISO 13400-3 DoIP,
ISO 11898-2 CAN HS,
Physical (layer 1) IEEE 802.3
ISO 15765-4 DoCAN
0.2 SAE document reference concept

ISO 27145 makes reference to several SAE documents which contain the terms, data and diagnostic trouble

code (DTC) definitions.
© ISO 2012 – All rights reserved v
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ISO 27145-3:2012(E)

ISO 27145-2 defines a common data dictionary for the ISO 27145 series, according to the definitions in the

following documents (see Figure 1).

— SAE J1930-DA: this digital annex contains all standardized naming objects, terms and abbreviated terms.

— SAE J1939 Companion Spreadsheet and SAE J1939-73: SAE J1939 Companion Spreadsheet indexes

names for suspect parameter numbers (SPNs) that provide an alternative presentation format for

SAE J2012-DA DTCs. SPNs are combined with failure mode indicators (FMIs) to form the full alternative

presentation. FMIs are described in SAE J1939-73:2010, Appendix A.

NOTE The SAE J1939 Companion Spreadsheet is a document which supplements the SAE J1939 family of

standards and contains SPNs and parameter group numbers (PGNs).

— SAE J1979-DA: this digital annex contains all standardized data items such as data identifiers (DIDs), test

identifiers (TIDs), monitor identifiers (MIDs) and infotype identifiers (ITIDs).

— SAE J2012-DA: this digital annex contains all standardized data items such as DTC definitions and FTB

(failure type byte) definitions.
ISO 27145-2
WWH-OBD
common data dictionary
1 2
SAE J1930-DA
digital annex of SAE J1939
SAE J1939-73:2010
SAE J2012-DA
[Companion
SAE J1979-DA electrical /electronic
[Appendix A]
digital annex of
digital annex of E/E systems diagnostic Spreadsheet]
diagnostic trouble
diagnostic test modes terms, definitions,
code definitions
abbreviations and
acronyms
Key
1 SAE digital annexes: data definitions
2 SAE J1939 series of documents: DTC definitions
Figure 1 — SAE digital annex document reference
0.3 SAE digital annex revision procedure

New regulatory requirements drive new in-vehicle technology to lower emissions, improve safety, etc. It is

important to standardize new technology-related OBD monitor data and DTCs in order to support the external

(off-board) “generic” test equipment. All relevant information is proposed by the automotive industry, represented

by members of the appropriate SAE task force.

ISO 27145-2 references a “Change request form” for use with new data items to be defined by the SAE

task force for standardization. It is intended that the standardized data items be defined in SAE J1930-DA,

SAE J1979-DA, SAE J2012-DA and SAE J1939. It is intended that the documents be published on the SAE

store website once the information has been balloted and approved.
vi © ISO 2012 – All rights reserved
---------------------- Page: 6 ----------------------
ISO 27145-3:2012(E)

The revision request forms and instructions for updating the registers to ISO 27145 can be obtained on the

following data registration websites:

— For SAE J1930-DA: http://www.sae.org/servlets/works/committeeHome.do?comtID=TEVDS7

The column entitled “Resources” shows a document with the title: J1930-DA_Revision_Request_Form.

doc. Double click on the name to download the document with the filename: “SAE_J1930-DA_Revision_

Request_Form.doc”.
— For SAE J1939: http://www.sae.org/

Search “J1939 Request”, select “J1939 Request Processing Group”, and select “J1939 Request Processing

Form and Guidelines”.

— For SAE J1979-DA: http://www.sae.org/servlets/works/committeeHome.do?comtID=TEVDS14

The column entitled “Resources” shows a document with the title: J1979-DA_Revision_Request_Form.

doc. Double click on the name to download the document with the filename: “SAE_J1979-DA_Revision_

Request_Form.doc”.

— For SAE J2012-DA: http://www.sae.org/servlets/works/committeeHome.do?comtID=TEVDS9

The column entitled “Resources” shows a document with the title: J2012-DA_Revision_Request_Form.

doc. Double click on the name to download the document with the filename: “SAE_J2012-DA_Revision_

Request_Form.doc”.
It is intended that the revision request form be filled out with the request.

It is intended that e-mails with completed revision request forms as attachments be sent to:

E-mail: saej1930@sae.org
E-mail: saej1979@sae.org
E-mail: saej2012@sae.org
E-mail: saej1939@sae.org
© ISO 2012 – All rights reserved vii
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INTERNATIONAL STANDARD ISO 27145-3:2012(E)
Road vehicles — Implementation of World-Wide Harmonized
On-Board Diagnostics (WWH-OBD) communication
requirements —
Part 3:
Common message dictionary
1 Scope

This part of ISO 27145 defines the implementation of a subset of unified diagnostic services (UDS) specified

in ISO 14229-1. The diagnostic services are used to communicate the diagnostic data defined in ISO 27145-2.

The subset of unified diagnostic services derives from the requirements stated in the WWH-OBD GTR (Global

technical regulation No. 5; see Reference [17]). The common message set defined in this part of ISO 27145 is

independent of the underlying transport, network, data link and physical layer. This part of ISO 27145 does not

specify any requirements for the in-vehicle network architecture.

This part of ISO 27145 is compatible with ISO 14229-1 and includes provisions to support the data set of

SAE J1979-DA and SAE J2012-DA WWH-OBD.

This part of ISO 27145 is intended for use with ISO 27145-4, which is the entry point for the protocol initialization

and is based on two different data links:

— Diagnostic communication over Controller Area Network (DoCAN), ISO 15765-1, ISO 15765-2, ISO 15765-4;

— Diagnostic communication over Internet Protocol (DoIP), ISO 13400 (all parts).

Due to the usage of standard network layer protocols, future extensions to optional physical layers (e.g.

wireless) are possible.

Based on the results of the initialization, the external test equipment determines which protocol and diagnostic

services are supported by the vehicle’s emissions-related system, i.e.
— legislated OBD: ISO 15031 (all parts);
— legislated WWH-OBD: ISO 27145 (all parts).

This part of ISO 27145 includes capabilities required to satisfy OBD regulations for multiple regions, vehicle

types, model years, and engine types. Those regulations are not yet final for some regions and are expected to

change in the future. This part of ISO 27145 does not attempt to interpret the regulations and does not include

applicability of the included diagnostic services and data parameters for various vehicle applications. It is

intended that users of this part of ISO 27145 verify the applicability of each of its clauses for a specific vehicle,

engine, model year and region.
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 14229-1, Road vehicles — Unified diagnostic services (UDS) — Part 1: Specification and requirements

ISO 14229-2, Road vehicles — Unified diagnostic services (UDS) — Part 2: Session layer interfaces

© ISO 2012 – All rights reserved 1
---------------------- Page: 8 ----------------------
ISO 27145-3:2012(E)

ISO 27145-1, Road vehicles — Implementation of World-Wide Harmonized On-Board Diagnostics (WWH-

OBD) communication requirements — Part 1: General information and use case definition

ISO 27145-2, Road vehicles — Implementation of World-Wide Harmonized On-Board Diagnostics (WWH-

OBD) communication requirements — Part 2: Common data dictionary (CDD)

ISO 27145-4, Road vehicles — Implementation of World-Wide Harmonized On-Board Diagnostics (WWH-

OBD) communication requirements — Part 4: Connection between vehicle and test equipment

3 Terms, definitions and abbreviated terms
3.1 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 27145-1, ISO 27145-2, ISO 14229-1

and the following apply.
3.1.1
global technical regulation
GTR

agreement establishing global technical regulations for wheeled vehicles and equipment and parts that can be

fitted and/or used on wheeled vehicles
3.2 Abbreviated terms
ASCII American standard code for information interchange
CDTC confirmed DTC
DID diagnostic data identifier
DoCAN diagnostic communication over controller area network
DoIP diagnostic communication over internet protocol
DTC diagnostic trouble code
DTCHB DTC high byte
DTCLB DTC low byte
DTCMB DTC middle byte
DTCS DTC severity
ECM engine control module
ECU electronic control unit
FMI failure mode indicator
FTB failure type byte
GTR global technical regulations
MI malfunction indicator
N/A not applicable
PDTC pending DTC
PDU protocol data unit
2 © ISO 2012 – All rights reserved
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ISO 27145-3:2012(E)
RID routine identifier
SFID sub-function identifier
SID service identifier
SODTC status of DTC
SPN suspect parameter number
TNCSLC test not completed since last clear
TNCTOC test not completed this operation cycle
UDS unified diagnostic services
VIN vehicle identification number
WUC warm-up cycle
WWH-OBD world-wide harmonized on-board diagnostics
4 Conventions

The ISO 27145 series is based on the conventions discussed in the OSI Service Conventions (ISO/IEC 10731)

as they apply to diagnostic services.
5 Document overview
Figure 2 shows the reference documents for the ISO 27145 series.
The ISO 27145 series specifies or includes the following references:

a) ISO 27145-1 specifies the general structure of the ISO 27145 series and the use cases applicable to

WWH-OBD GTR.
b) ISO 27145-2 specifies the common data dictionary with references to:
1) SAE J1930-DA, which defines the terms, definitions, abbreviated terms, etc.;
2) SAE J1939 Companion Spreadsheet, which specifies the SPNs;
3) SAE J1939-73:2010, Appendix A, which specifies the FMIs;
4) SAE 1979-DA, which specifies all data items;
5) SAE J2012-DA, which specifies the DTC definitions and FTB definitions.

NOTE The SAE J1939 series of documents is concerned with the definition of emissions-related SPNs and FMIs

for use as DTCs.

c) This part of ISO 27145 specifies the diagnostic services defined in ISO 14229-1 that are applicable to

WWH-OBD GTR.

d) ISO 14229-2 specifies the standardized service primitive interface to separate application and session

layers from protocol transport and network layers.

e) ISO 27145-4 specifies the initialization procedure and includes references to:

1) ISO 15765-4 DoCAN;
2) ISO 13400 (all parts) DoIP.
© ISO 2012 – All rights reserved 3
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ISO 27145-3:2012(E)
Unified diagnostic services (UDS)
ISO 27145-1
WWH-OBD
general information and
use case definition
ISO 27145-3
SAE J1930-DA
ISO 14229-1 UDS
1 : 1
WWH-OBD
specification and subset Terms , ..
OSI layer 7
common message
requirements
Application
dictionary
SAE J1979-DA
1 : 1
PIDs, MIDs, RIDs,
ITIDs
ISO 27145-2
WWH-OBD
OSI layer 6
common data
Presentation
dictionary
SAE J2012-DA
1 : 1
WWH-OBD DTCs
SAE J1939 Companion
ISO 14229-2 UDS ISO 14229-2 UDS
1 : 1
OSI layer 5 Spreadsheet
session layer interfaces session layer interfaces
subset
Session
SAE J1939-73:2011,
Appendix A
Standardized service primitive interface
Diagnostic communication over CAN and Internet Protocol
DoCAN
DoIP
OSI layer 4
Transport
ISO 15765-2 DoCAN
ISO 13400-2 DoIP
transport protocol
transport protocol
and
and
network
network
layer services
layer services
OSI layer 3
Network
ISO 27145-4
ISO 15765-4 DoCAN
WWH-OBD
requirements for
connection between
emissions-related
systems vehicle and test
equipment
OSI layer 2
ISO 11898-1 CAN
Data link
data link layer
ISO 13400-3 DoIP
and physical signalling
wired vehicle
interface based
ISO 11898-2 CAN
on IEEE 802.3
high-speed
medium access unit
OSI layer 1
Physical

Figure 2 — Reference documents for implementation of WWH-OBDonCAN and WWH-OBDonIP

according to the OSI model
6 Unified diagnostic services (UDS) applicable to WWH-OBD
6.1 General

This clause defines how the diagnostic services defined in ISO 14229-1 apply to ISO 27145. For each applicable

service, the applicable sub-function and data parameters are defined.
4 © ISO 2012 – All rights reserved
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ISO 27145-3:2012(E)

Subclauses 6.3 to 6.8 define additional requirements and/or restrictions for the ISO 14229-1 services that are

supported for WWH-OBD in this part of ISO 27145.

NOTE The sub-function parameter definitions take into account that the most significant bit is used for the

suppressPosRspMsgIndicationBit parameter, as defined in ISO 14229-1.
6.2 UDS on WWH-OBD overview

This part of ISO 27145 applies the diagnostic services defined in ISO 14229-1 for WWH-OBD-compliant

implementations. Table 2 references the ISO 14229-1 services that apply to UDS implementations which meet

WWH-OBD requirements.

Table 2 contains all services that apply from ISO 14229-1. For each service, the required support for

sub-functions and data parameters is defined. Implementation of additional services from ISO 14229-1, that

are not listed in Table 2, is entirely at the discretion of the implementer, except where local regulations define

additional requirements. Additional detail for each service is given by the subclause referenced in the rightmost

column of Table 2.
Table 2 — Overview of applicable ISO 14229-1 UDS and data ranges
UDS name SID SFID
Sub-function name Comment Ref.
(ISO 14229-1) value value
Data transmission functional unit
ReadDataByIdentifier 0x22 — N/A This service provides read capabilities for 6.5
static and dynamic data.
Stored data transmission functional unit

ReadDTCInformation 0x19 0x04 reportDTCSnapshotRecordBy- This service provides read capabilities for 6.6

DTCNumber DTC information.
0x06 reportDTCExtendedData-
RecordByDTCNumber
The sub-functions are mandatory for WWH-
OBD-compliant servers.
0x42 reportWWHOBDDTCByMask-
Record
ClearDiagnostic- 0x14 — N/A This service provides clear DTC information 6.7
Information capability.
To clear emissions system group information,
the parameter groupOfDTC = 0xFFFF33.
Remote activation of routine functional unit

RoutineControl 0x31 0x01 startRoutine This service provides control capability for 6.8

routines.
This sub-function is mandatory for WWH-
OBD-compliant servers.
6.3 Electronic control unit (ECU) response message length too long

If the ECU response message exceeds the length supported by the underlying network layer that has been

implemented, a negative response code 0x14 shall be sent by the ECU instead of a positive response message.

6.4 Message byte order

Alphanumeric data derived from SAE J1979-DA and SAE J2012-DA shall be transmitted with the most

significant byte first (MSB).

Unless otherwise specified, alphanumeric characters shall conform to the ISO Latin 1 ASCII character set as

specified in ISO 27145-2.

See ISO 27145-2 for the message byte order for DTCs according to SAE J1939 Companion Spreadsheet

(SPN) and SAE J1939-73:2010, Appendix A (FMI).
© ISO 2012 – All rights reserved 5
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ISO 27145-3:2012(E)
6.5 ReadDataByIdentifier (0x22) service
6.5.1 General

This part of ISO 27145 complies with the requirements of ISO 14229-1. Subclause 6.5.2 defines additional

requirements or imposes restrictions applicable to the service referenced.
6.5.2 WWH-OBD-specific requirements
6.5.2.1 Requirement — Minimum number of DIDs per request to be supported

Table 3 specifies a minimum number of DIDs per request that shall be supported by the server(s) as part of a

request message of the service ReadDataByIdentifier, even if the server(s) might not have support for the data

referenced by the DID(s).

Table 3 — Requirement definition: Minimum number of DIDs per request to be supported by a server

Requirement Minimum number of DIDs per request to be supported by a server
name
Affects WWH-OBD server(s)

Brief The ReadDataByIdentifier service allows the client to request data record values from the server(s)

description identified by one or more DIDs. The client request message contains one or more DataIdentifier

values that identify data record(s) maintained by the server (see ISO 27145-2).

Upon receiving a ReadDataByIdentifier request, the server shall access the data elements of the

records specified by the DID parameter(s) and transmit their value in one single ReadDataByIdentifier

positive response message containing the associated dataRecord parameter(s).

Requirement The server shall support at least six DIDs simultaneously in a request and response message if

requested by the external test equipment.
6.6 ReadDTCInformation (0x19) service
6.6.1 General

This part of ISO 27145 complies with the requirements of ISO 14229-1. Subclause 6.6.2 defines additional

requirements or imposes restrictions applicable to the service referenced.
6.6.2 WWH-OBD-specific requirements
6.6.2.1 Requirement — DTC format identification

Table 4 specifies the two DTC formats which shall be supported by the GTR WWH-OBD-compliant server(s)

and external test equipment.
6 © ISO 2012 – All rights reserved
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ISO 27145-3:2012(E)
Table 4 — Requirement definition: DTC format identification
Requirement DTC format identification
name
Affects Client(s), WWH-OBD server(s)

Brief The DTCFormatIdentifier defined in ISO 14229-1 is a 1-byte parameter value which defines the format

description of a DTC reported by the server.

Requirement DTCs reported by services and sub-functions in accordance with ISO 27145 shall always use only one

of the two formats specified in ISO 27145-2:

— SAE_J2012-DA_DTCFormat_04: This parameter value identifies the WWH-OBD DTC format

reported by the server, as defined in the SAE J2012-DA specification.

— SAE_J1939-73_DTCFormat: This parameter value identifies the DTC format reported by the

server, as defined in the SAE J1939-73 specification.
The values of the DTCFormatIdentifier are specified in ISO 14229-1.
6.6.2.2 Requirement — Support of DTCStatusAvailabilityMask parameter

Table 5 specifies the bits which are defined in the same way as for statusOfDTC and which represent the status

bits that are supported by GTR WWH-OBD-compliant server(s). Bits that are not supported by the server(s)

shall be set to 0.
Table 5 — Requirement definition: Support of DTCStatusAvailabilityMask parameter
Requirement Support of DTCStatusAvailabilityMask parameter
name
Affects WWH-OBD server(s)

Brief The DTCStatusAvailabilityMask parameter indicates the statusOfDTC bits supported by GTR

description WWH-OBD-compliant server(s).

NOTE It is up to the manufacturer to support additional bits per DTC as deemed necessary to fully support

their diagnostics.

Requirement The GTR WWH-OBD-compliant server shall support at least the following statusOfDTC parameter

bits per DTC:
— bit 2, pendingDTC (PDTC);
— bit 3, confirmedDTC (CDTC);
— bit 4, testNotCompletedSinceLastClear (TNCSLC);
— bit 6, testNotCompletedThisOperationCycle (TNCTOC).

The values of the DTCStatusAvailabilityMask parameter are specified in ISO 14229-1.

6.6.2.3 Requirement — Support of DTCSeverityAvailabilityMask parameter

Table 6 specifies the bits which are defined in the same way as for DTCSeverity and DTC Class and which

represent the status bits that are supported by GTR WWH-OBD-compliant server(s). Bits that are not supported

by the server(s) shall be set to 0.
© IS
...

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