ISO 27145-3:2012

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 2012
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ii © ISO 2012 – All rights reserved

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
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

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 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

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
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 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

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.
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

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).
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

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.
Table 6 — Requirement definition: Support of DTCSeverityAvailabilityMask parameter
Requirement Support of DTCSeverityAvailabilityMask parameter
name
Affects WWH-OBD server(s)
Brief The DTCSeverityAvailabilityMask parameter indicates the DTC Class bits supported by GTR WWH-
description OBD-compliant server(s).
Requirement The GTR WWH-OBD-compliant server shall support at least the following DTC Class parameter bits:
— bit 1, Class_1 (Class A);
— bit 2, Class_2 (Class B1);
— bit 3, Class_3 (Class B2);
— bit 4, Class_4 (Class C).
The values of the DTC Class parameter are specified in ISO 14229-1.
6.6.2.4 Requirement — Request mask handling of DTC Severity Mask Record
The requirements specified in this section allow for the implementation of the malfunction classification concept
defined in the GTR WWH-OBD, Module B, section 4.5 (see Reference [17]).
Table 7 specifies the WWH-OBD GTR DTC masking requirements. The following definitions apply:
— AND, OR logical operation;
— & bitwise AND;
— && logical AND;
— == equal to (comparison operator);
— = assignment operator;
— != not equal to.
6.6.2.5 GTR WWH-OBD DTC status diagram
Figure 3 shows an implementation example of the GTR WWH-OBD DTC state timings depending on operation
cycle and monitoring results. Additionally, the diagram describes related states of the DTC status bits defined
by ISO 14229-1/ISO 27145. Finally, the diagram illustrates how the client displays GTR WWH-OBD-compliant
DTC states based on the ISO 14229-1 status bit definitions. Reusing the DTC status bit definitions forces a
specific implementation of the GTR WWH-OBD DTC status requirements but fully satisfies them.
The following conditions apply:
— A DTC will be reported as “Confirmed & Active” for this operation sequence where the malfunction occurs
again after the DTC has been reported as “Previously Active”.
— Since the DTC status is changed from “Previously Active” to “Confirmed & Active” one operation sequence
earlier than required, presuming the DTC was in “Previously Active” state, the related MI (short/continuous)
illuminates one operation sequence prior to when required.
— The warm-up cycle counter indicating the number of cycles during which a DTC was in “Previously Active”
status (aging counter) counts upward from zero (0) only if the related MI has been de-activated.
The implementation shown in Figure 3 is an example and for illustration purposes only. It shows the discriminatory
malfunction indicator (MI) for Class B2 malfunctions.
8 © ISO 2012 – All rights reserved

When mapping the GTR DTC status to DTC status bits (statusOfDTC) defined according to ISO 14229-1, the
definitions in Table 8 apply.
Table 7 — Requirement definition: Request mask handling of DTC Severity Mask Record
Requirement Request mask handling of DTC Severity Mask Record
name
Affects Client(s), server(s)
Brief The DTC Severity Mask Record consists of three different request mask elements, namely the DTC
description Severity Mask byte and the DTC Status Mask, where the DTC Severity Mask byte is separated into
DTC Severity Mask (bits 5-7) and DTC Class Mask (bits 0-4). Each of these three mask elements
needs to be processed separately for each individual DTC that an ECU supports. A DTC is only
included in the positive response to a sub-function 0x42 request if at least the processing of the DTC
Status Mask and the DTC Class Mask yielded a non-zero result.
Pre- — Each individual WWH-OBD-relevant DTC is assigned to a unique fault class (A, B1, B2, C).
requisites This means that, for each DTC of functional group 0x33, an ECU shall set one bit out of the four
dedicated DTC class bits to one (1), indicating that the respective DTC belongs to one unique
fault class.
— When requesting DTCs by sub-function 0x42, the DTC Severity Mask (bit 5-7) shall only be
considered if at least one bit of this mask element is set to one.
Requirement If the server does not implement DTC Severity, the GTR WWH-OBD-compliant server/ECU shall
perform a bitwise logical ANDing of
— the DTC Status Mask and the actual DTC Status, and
— the requested DTC Class Mask and the actual DTC class
for each DTC upon request of the test equipment.
The positive response message shall include only those DTCs for which both ANDing operations
yielded a non-zero result.
(((DTCStatusMask & statusOfDTC) !=0) && ((DTCClassMask & actual DTC class) !=0)) == TRUE
If the server implements DTC Severity, the GTR WWH-OBD-compliant server/ECU shall perform a
bitwise logical ANDing of
— the DTC Status Mask and the actual DTC Status,
— the requested DTC Severity Mask and the actual DTC Severity, and
— the requested DTC Class Mask and the actual DTC class
for each DTC upon request of the test equipment.
The positive response message shall include only those DTCs for which all three ANDing operations
yielded a non-zero result.
(((DTCStatusMask & statusOfDTC) !=0) && ((DTCClassMask & actual DTC class) !=0) &&
((DTCSeverityMask & actual DTC Severity) !=0)) == TRUE
Table 8 — Mapping of GTR WWH-OBD DTC status and ISO 14229-1 statusOfDTC
DTC status according DTC status bits (statusOfDTC) according to ISO 14229-1
to GTR WWH-OBD
Potential Pending AND (NOT statusOfDTC.2 (PDTC) AND [NOT statusOfDTC.3 (CDTC)]
Confirmed)
Pending Pending statusOfDTC.2 (PDTC)
Confirmed AND Active Confirmed AND Pending statusOfDTC.3 (CDTC) AND statusOfDTC.2 (PDTC)
Previously Active Confirmed AND (NOT statusOfDTC.3 (CDTC) AND [NOT statusOfDTC.2 (PDTC)]
Pending)
operating sequence number M M+1 N N+1 M' M'+1 N' N'+1 N'+2 N'+3 M'' M''+1 … N'' N''+1 N''+2 N''+3 N''+4 … N''+ n

YES
// //
//
failure
NO //
//
40/200h
//
WUCs / operating hours
//
0 // //
w/o malfunction
//
YES
Potential
NO
// //
// // //
YES //
// //
Pending
NO //
//
YES
// //
//
Confirmed & Active
NO
// //
YES
// //
Previously Active
NO
// // //
short // //
//
MI (class B2 malfunction)
OFF
// //
continuous //
// //
short
MI (class A malfunction
OFF //
//
YES //
// //
statusOfDTC.2 (PDTC)
NO //
//
YES
// // //
// //
statusOfDTC.3 (CDTC)
NO
YES
statusOfDTC.4 (TNCSLC)
NO //
// //
// //
YES //
// // // //
statusOfDTC.6 (TNCTOC)
NO
YES
// //
//
Pending
NO
//
//
YES
// // //
Confirmed AND Active
NO
//
//
YES
// //
Previously Active
NO
// // //
short
// // //
MI (class B2 malfunctio n)
OFF
// //
continuous
// // //
short
MI (class A malfunction)
OFF
// //
Key
point at which monitoring of the concerned malfunction occurs
status defined by the manufacturer as allowed by the GTR
// operating sequence
M first operating sequence during which a malfunction is detected
N first operating sequence during which no malfunction is detected
M′, N′ second operating sequence during which a malfunction is detected/no malfunction is detected
M″, N″ third operating sequence during which a malfunction is detected/no malfunction is detected
Figure 3 — GTR WWH-OBD DTC status diagram
Table 9 defines examples based on the minimum requirements for how the client retrieves one or multiple
GTR WWH-OBD DTC(s) of a specific status and class. This table covers all use cases required by the GTR
WWH-OBD, Module B. The request message has been defined under the assumption that the server does not
support DTC Severity (i.e. bits 7–5 = 0).
10 © ISO 2012 – All rights reserved
statusOfDTC according
to ISO 14229-1
GTR status
Client status with
required MI status
Table 9 — WWH-OBD DTC retrieval examples
DTCStatus- DTC Severity-
DTC status and class as defined Request (Req.) and Response
Mask Mask byte
in the use cases of ISO 27145-1 (Resp.) message
bits 7 . 0 bits 7 . 0
Confirmed and Active DTCs for Class A Req. 0x19, 0x42, 0x33, 0x08,
malfunctions 0x02
Resp. 0x59, 0x42, 0x33, 0x5C,
DTC format = SAE_J2012-DA_
0x1E, 0x04,
DTCFormat_04
[0x02, DTCHB, DTCMB,
0000 1000 0000 0010
b b
The client shall identify the DTCs matching
DTCLB, SODTC] ., […]
the confirmed and active status – remove all
other DTCs from the result list.
See Figure 4 for a description of client
behaviour.
Confirmed and Active DTCs for Class B (B1 Req. 0x19, 0x42, 0x33, 0x08,
and B2) malfunctions 0x0C
Resp. 0x59, 0x42, 0x33, 0x5C,
DTC format = SAE_J2012-DA_
0x1E, 0x04,
DTCFormat_04
[0x0C, DTCHB, DTCMB,
0000 1000 0000 1100
b b
The client shall identify the DTCs matching
DTCLB, SODTC] ., […]
the confirmed and active status – remove all
other DTCs from the result list.
See Figure 5 for a description of client
behaviour.
Confirmed and Active DTCs for Class C Req. 0x19, 0x42, 0x33, 0x08,
malfunctions 0x10
Resp. 0x59, 0x42, 0x33, 0x5C,
DTC format = SAE_J2012-DA_
0x1E, 0x04,
DTCFormat_04
[0x10, DTCHB, DTCMB,
0000 1000 0001 0000
b b
The client shall identify the DTCs matching
DTCLB, SODTC] ., […]
the confirmed and active status – remove all
other DTCs from the result list.
See Figure 6 for a description of client
behaviour.
Pending DTCs and their associated class Req. 0x19, 0x42, 0x33, 0x04,
0x1E
DTC format = SAE_J2012-DA_
Resp. 0x59, 0x42, 0x33, 0x5C,
DTCFormat_04
0x1E, 0x04,
The client shall identify the DTCs matching
0000 0100 0001 1110
[DTCS, DTCHB, DTCMB, b b
the pending status – remove all other DTCs
DTCLB, SODTC] ., […]
from the result list.
See Figure 7 for a description of client
behaviour.
Previously Active DTCs and their associated Req. 0x19, 0x42, 0x33, 0x08,
class 0x1E
Resp. 0x59, 0x42, 0x33, 0x5C,
DTC format = SAE_J2012-DA_
0x1E, 0x04,
DTCFormat_04
[DTCS, DTCHB, DTCMB,
0000 1000 0001 1110
b b
The client shall identify the DTCs matching
DTCLB, SODTC] ., […]
the previously active status – remove all other
DTCs from the result list.
See Figure 8 for a description of client
behaviour.
Figures 4 to 8 illustrate the definition of the client’s request message and the server’s action in order to provide
the requested DTC information in a positive response message.
client server
request Confirmed AND Active DTCs (0x19, 0x42, 0x33, 0x08, 0x02)
Compile list of DTCs
matching DTC
return list of DTCs matching DTC Severity Mask
Severity Mask Record ()
Record (0x59, 0x42, 0x33, 0x5C, 0x1E, 0x04
[0x02, DTCHB, DTCMB, DTCLB, SODTC], …, […])
Pseudo Code:
(((DTCStatusMask & statusOfDTC ) !=0) &&
((DTCClassMask & actual DTC class) !=0)) = TRUE
[SODTC == XXXX 11XX b]:
Identify DTCs matching the
confirmed and active status-
remove all others from result list()
Figure 4 — Retrieval of Confirmed AND Active DTCs of Class A malfunctions
client server
request Confirmed AND Active DTCs (0x19, 0x42, 0x33, 0x08, 0x0C)
Compile list of DTCs
matching DTC
return list of DTCs matching DTC Severity Mask
Severity Mask Record()
Record (0x59, 0x42, 0x33, 0x5C, 0x1E, 0x04
[0x0C, DTCHB, DTCMB, DTCLB, SODTC], …, [.])
Pseudo Code:
[SODTC == XXXX 11XX b]: (((DTCStatusMask & statusOfDTC) !=0) &&
Identify DTCs matching the ((DTCClassMask & actual DTC class) !=0)) = TRUE
confirmed and active status -
remove all others from result list ()
Figure 5 — Retrieval of Confirmed AND Active DTCs of Class B1 and B2 malfunctions
client server
request Confirmed AND Active DTCs (0x19, 0x42, 0x33, 0x08, 0x10)
Compile list of DTCs
return list of DTCs matching DTC Severity Mask matching DTC
Record(0x59, 0x42, 0x33, 0x5C, 0x1E, 0x04 Severity Mask Record ()
[0x10, DTCHB, DTCMB, DTCLB, SODTC], …, […])
Pseudo Code:
[SODTC == XXXX 11XX b]: (((DTCStatusMask & statusOfDTC ) !=0) &&
((DTCClassMask & actual DTC class) !=0)) = TRUE
Identify DTCs matching the
confirmed and active status -
remove all others from result list()
Figure 6 — Retrieval of Confirmed AND Active DTCs of Class C malfunctions
12 © ISO 2012 – All rights reserved

client server
request Pending DTCs (0x19, 0x42, 0x33, 0x04, 0x01E)
Compile list of DTCs
matching DTC
return list of DTCs matching DTC Severity Mask
Severity Mask Record ()
Record(0x59, 0x42, 0x33, 0x5C, 0x1E, 0x04
[DTCS, DTCHB, DTCMB, DTCLB, SODTC], …, […])
Pseudo Code:
(((DTCStatusMask & statusOfDTC) !=0) &&
[SODTC == XXXX 01XX b ]:
((DTCClassMask & actual DTC class) !=0)) = TRUE
Identify DTCs matching the
pending status - remove all
others from result list ()
Figure 7 — Retrieval of Pending DTCs and their associated class
client server
request Previously Active DTCs (0x19, 0x42, 0x33, 0x08, 0x01E)
Compile list of DTCs
matching DTC
return list of DTCs matching DTC Severity Mask
Severity Mask Record ()
Record(0x59, 0x42, 0x33, 0x5C, 0x1E, 0x04
[DTCS, DTCHB, DTCMB, DTCLB, SODTC], …, […])
Pseudo Code:
(((DTCStatusMask & statusOfDTC ) !=0) &&
[SODTC == XXXX 10XX b ]:
((DTCClassMask & actual DTC class) !=0)) = TRUE
Identify DTCs matching the
previously active status -
remove all others from result list()
Figure 8 — Retrieval of Previously Active DTCs and their associated class
6.6.2.6 Requirement — FunctionalGroupIdentifier
Table 10 specifies the purpose and requirements of the FunctionalGroupIdentifier.
Table 10 — Requirement definition: FunctionalGroupIdentifier
Requirement FunctionalGroupIdentifier
name
Affects Client(s), server(s)
Brief The FunctionalGroupIdentifier has been introduced to distinguish commands sent by the test
description equipment between different functional system groups within an electrical architecture which consists
of many different servers. If a server has implemented software of the emissions system as well as
other systems which may be inspected during an I/M test, it is important that only the DTC information
of the requested functional system group is reported. An emissions I/M test should not be failed
because another functional system group, e.g. safety system group, has DTC information stored.
The values of the FunctionalGroupIdentifier are specified in ISO 14229-1.
Requirement The FunctionalGroupIdentifier value for the WWH-OBD emissions system group is defined in
ISO 14229-1.
6.6.3 WWH-OBD-specific ReadDTCInformation service examples
WWH-OBD-specific ReadDTCInformation service examples are described in A.3.
6.7 ClearDiagnosticInformation (0x14) service
6.7.1 General
This part of ISO 27145 complies with the requirements of ISO 14229-1. Subclause 6.7.2 defines additional
requirements or imposes restrictions applicable to the service referenc
...