OBD (On Board Diagnostics)

information, report on OBD (On Board Diagnostics)

1. •Made by-
•Pawan Shetty (175052)
•Aditi Shinde(175053)
•Purvesh Shinde (175054)
•Yameen Siddiqui
(175055)

2. INTRODUCTION
Vehiclestodayaremuchmoreintelligentthantheywereyearsback.The
traditionalvehicletimedtheignitionofthesparkusingmechanicaldistributors.
Thismethodofcoordinatingthetimingofthesparkdeliverywhenthefuelandair
mixturewerecompressedintheenginecylinderswasn’tideal.
Asyearswenton,theECUbecamemorecapableofsupplyingdiagnosticand
sensordatatohelpmechanicsidentifythesourceofproblemsthatariseinthe
enginemanagementsystem.
Eventuallyastandardwascreatedthatallmanufacturerswereencouraged
tofollow.ThestandardbecamecommonlyknownasOnboardDiagnostics(OBD).
Theintroductionofthestandardwasinanefforttoencouragevehicle
manufacturerstodesignmorereliableemissioncontrolsystems.OBD-IIisan
enhancementoftheOBDstandardthatwasintroducedlaterandmademandatory.
Themodernvehicle'son-board-diagnostics(OBD-II)providesarepair
technicianwithaccesstoinformationforvariousvehiclesub-systems.The
amountofdiagnosticinformationavailableviaOBD-IIhasvariedwidelysinceits
introductioninthemid1990's.

3. ON-BOARD DIAGNOSTICS -I
AmilestoneforautomotiveefficiencyarrivedintheformsofOn-board
computersOnBoardDiagnostics,OBD,beginningin1980.Thesecomputerswould
monitorthefuelinjectionsystemsandwouldhavesimplecapabilitiesand
adjustments,inreturn,werethestartofsomethinggreattocome.TheGeneral
MotorsCompanybecamethefirsttobuildaninterfaceintheirvehiclein1982,
theAssemblyLineCommunicationsLink.By1986,theALCL,knownastheALDL,
AssemblyLineDiagnosticLink,seenbelowinFigureTerminalIdentificationforOn
BoardDiagnosticsPort,haddevelopedintoamuchbettersystemwherethe
problemwithinconsistencyincommunicationlinkshadbeenresolvedwiththe
implementationofTheUniversalAsynchronousReceiver/Transmitter.Thisbecame
knownasOBD-I.

4. ON-BOARD DIAGNOSTICS -II
OBD-IIisanimprovementoverOBD-Iinbothcapabilityandstandardization.
TheOBD-IIstandardspecifiesthetypeofdiagnosticconnectoranditspinout,the
electricalsignallingprotocolsavailable,andthemessagingformat.Italsoprovidesa
candidatelistofvehicleparameterstomonitoralongwithhowtoencodethedatafor
each.Thereisapinintheconnectorthatprovidespowerforthescantoolfromthe
vehiclebattery,whicheliminatestheneedtoconnectascantooltoapowersource
separately.
TheOBD-IIstandardprovidesalistofstandardizedDTCs.Asaresultofthis
standardization,asingledevicecanquerytheon-boardcomputer(s)forthese
parametersinanyvehicle.OBD-IIstandardizationwaspromptedtosimplifydiagnosis
ofincreasinglycomplicatedemissionsequipment,andthoughonlyemission-related
codesanddataarerequiredtobetransmittedthroughitaccordingtoU.S.Legislation.

5. OBD-II DIAGNOSTIC CONNECTOR
TheDLC(DataLinkConnectororDiagnosticLinkConnector)isthe
standardized16-cavityconnectorwherediagnosticscantoolsinterfacewith
thevehicle’sonboardcomputer.theDLCisusuallylocated12inchesfromthe
centeroftheinstrumentpanel(dash),underoraroundthedriver’ssideformost
vehicles.
Since1996,thedatalinkconnector(DLC)isastandardized16cavity
connectorshownbelow.Connectordesignandlocationisdictatedbyan
industrywidestandard.VehiclemanufacturerscanusetheemptyDLCcavities
forwhatevertheywouldlike.
TheSAEJ1962specificationprovidesfortwostandardizedhardware
interfaces,calledtypeAandtypeB.Botharefemale,16-pin(2x8),D-shaped
connectors,andbothhaveagroovebetweenthetworowsofpins,buttypeB's
grooveisinterruptedinthemiddle.

7. OBD PROTOCOL LIST
An OBD2 compliant vehicle can use any of the five
communication protocols:
1.SAE J1850 PWM
2.SAE J1850 VPW
3.ISO9141-2
4.ISO14230-4 (KWP2000)
5.ISO 15765-4/SAE J2480
AllOBD-IIpinoutsusethesameconnector,but
differentpinsareusedwiththeexceptionofpin4(battery
ground)andpin16(batterypositive).

8. OBD TROUBLE CODES
OBD-IIDiagnosticTroubleCodes(DTCS)arecodesthatarestored
bytheon-boardcomputerdiagnosticsysteminresponsetoaproblem
foundinthevehicle.thesecodesidentifyaparticularproblemareaandare
intendedtoprovideyouwithaguideastowhereafaultmightbeoccurring
withinavehicle.OBDIIDiagnosticTroubleCodesconsistofafive-digit
alphanumericcode.thefirstcharacter,aletter,identifieswhichcontrol
systemsetsthecode.theotherfourcharacters,allnumbers,provide
additionalinfomationonwheretheDTCoriginatedandtheoperating
conditionsthatcausedittoset.

9. OBD APPLICATIONS
Various tools are available that plug into the
OBD connector to access OBD functions such as-
Hand-held scan tools
Mobile device-based tools and analysis
PC-based scan tools and analysis platforms
Data loggers
Emission testing
Driver's supplementary vehicle instrumentation
Vehicle telematics

10. STANDARDS DOCUMENTS
SAE standards documents on OBD-I
J1962 –Defines the physical connector used for the OBD-II interface
J1978 –Defines minimal operating standards for OBD-II scan tools
J1979 –Defines standards for diagnostic test modes
J2012 –Defines standards trouble codes and definitions.
J2178-2 –Gives data parameter definitions
J2178-3 –Defines standards for network message frame IDs for single byte
headers
J2178-4 –Defines standards for network messages with three byte
headers.
SAE standards documents on HD (heavy duty) OBD
J1939 –Defines a data protocol for heavy duty commercial vehicles

11. ISO STANDARDS
ISO8093:Roadvehicles--Diagnostictestingofelectronicsystems
ISO9141:Roadvehicles—Diagnosticsystems.International
OrganizationforStandardization,1989.
ISO11898:Roadvehicles—Controllerareanetwork(CAN).
InternationalOrganizationforStandardization,2003.
ISO14230:Roadvehicles—Diagnosticsystems—KeywordProtocol
2000,InternationalOrganizationforStandardization,1999.
ISO15765:Roadvehicles—DiagnosticsonControllerAreaNetworks
(CAN).InternationalOrganizationforStandardization,2004.
ISO15031:Communicationbetweenvehicleandexternalequipmentfor
emissions-relateddiagnostics,InternationalOrganizationfor
Standardization,2010.
ISO14320nodata

12. SECURITY ISSUES
ResearchersexaminedthesecurityaroundOBD,
Andfoundthattheywereabletogaincontrolover
manyvehiclecomponentsviatheinterface.Further
more,theywereabletouploadnewfirmwareintothe
enginecontrolunits.Theirconclusionisthatvehicle
Embeddedsystemsarenotdesignedwithsecurityinmind.
Theprimarycausesofthisvulnerabilitylieinthetendencyforvehicle
manufacturerstoextendthebusforpurposesotherthanthoseforwhichitwas
designed,andthelackofauthenticationandauthorizationintheOBDspecifications,
whichinsteadrelylargelyonsecuritythroughobscurity.

13. CONCLUSION
OBD-IIisnolongeronlyusedbyprofessionalstorepair
vehicles.OBD-IIinformationiscommonlyusedbyvehicle
telematicsdevicesthatperformfleettracking,monitorfuelefficiency,
preventunsafedriving,aswellasforremotediagnosticsandbypay-
as-you-driveinsurance.Althoughoriginallynotintendedfortheabove
purposes,commonlysupportedOBD-IIdatasuchasvehicle
speed,RPM,andfuellevelallowGPS-basedfleettrackingdevicesto
monitorvehicleidlingtimes,speeding,andover-revving.Bymonitoring
OBDIIDTCsacompanycanknowimmediatelyifoneofitsvehicles
hasanengineproblemandbyinterpretingthecodethenatureofthe
problem.OBDIIisalsomonitoredtoblockmobilephoneswhendriving
andtorecordtripdataforinsurancepurposes.

14. THANK YOU