Editing On-board diagnostics (section)

== History ==

{{prose|section|date=September 2021}}

* 1968: [[Volkswagen]] introduces the first on-board computer system, in their [[fuel-injected]] [[Volkswagen Type 3|Type 3]] models. This system is entirely analog with no diagnostic capabilities.
* 1975: Bosch and Bendix EFI systems are adopted by major automotive manufacturers to improve tailpipe (exhaust) emissions. These systems are also analog, though some provide rudimentary diagnostic capability through factory tools, such as the Kent Moore J-25400, compatible with the [[Datsun 280Z]], and the [[Cadillac Seville#First generation (1976–1979)|Cadillac Seville.]]
* 1980: [[General Motors]] introduces the first data link on their 1980 [[Cadillac Eldorado]] and Seville models. Diagnostic Trouble Codes (DTCs) are displayed through the electronic climate control system's digital readout when in diagnostic mode.<ref>{{Cite book|title=Digital Electronic Fuel Injection 16007.02-1|publisher=GM Product Service Training|date=Aug 1979}}</ref>
* 1981: [[General Motors]] introduced its "Computer Command Control" system on all US passenger vehicles for model year 1981. Included in this system is a proprietary 5-pin [[ALDL]] that interfaces with the [[Engine Control Module]] (ECM) to initiate a diagnostic request and provide a serial data stream. The protocol communicates at 160 [[baud]] with [[Pulse-width modulation]] (PWM) signaling and monitors all engine management functions. It reports real-time sensor data, component overrides, and Diagnostic Trouble Codes. The specification for this link is as defined by GM's Emissions Control System Project Center document XDE-5024B.<ref>{{Cite magazine|magazine=GM Today|title=GM Today|volume=6|issue=8|publisher=General Motors|date=September 1980}}</ref><ref>{{Cite journal |first1=Ronald W. |last1=Cox |title=Local Area Network Technology Applied to Automotive Electronic Communications |journal=IEEE Transactions on Industrial Electronics |volume=32 |issue=4 |pages=327–333 |date=November 1985|doi=10.1109/TIE.1985.350105 |s2cid=19426686 }}</ref>
* 1982: [[RCA]] defines an analog STE/ICE (simplified test equipment for internal combustion engines) vehicle diagnostic standard used in the [[Commercial Utility Cargo Vehicle|CUCV]], [[M60 tank]] and other military vehicles of the era for the US Army.<ref>{{cite web |url=https://apps.dtic.mil/dtic/tr/fulltext/u2/a181563.pdf|archive-url=https://web.archive.org/web/20200806031241/https://apps.dtic.mil/dtic/tr/fulltext/u2/a181563.pdf|url-status=live|archive-date=August 6, 2020| title=STE/ICE Design Guide for Vehicle Diagnostic Connector Assemblies|publisher=Department of the Army|location=US|access-date=2020-05-16|date=1982-08-01}}</ref>
* 1986: [[General Motors]] introduces an upgraded version of the ALDL protocol, which communicates at 8192 baud with half-duplex [[UART]] signaling on some models.
* 1988: The [[California Air Resources Board]] (CARB) requires that all new vehicles sold in [[California]] from 1988 onward have some basic OBD capability (such as detecting problems with fuel metering and [[Exhaust gas recirculation]].)<ref>{{cite web |url=http://www.arb.ca.gov/msprog/obdprog/obdfaq.htm |title=On-Board Diagnostic II (OBD II) Systems - Fact Sheet / FAQs |publisher=[[California Air Resources Board]] |location=US |date=2009-09-28 |archive-date=June 27, 2013 |archive-url=https://web.archive.org/web/20130627181224/http://www.arb.ca.gov/msprog/obdprog/obdfaq.htm |url-status=dead }}</ref><ref name="Ford manual">{{cite book |title=Ford Powertrain Control and Emissions Diagnostic Manual for Gasoline Engines |publisher=Ford Motor Company |date=2011-06-09}}</ref> These requirements are generally referred to as "OBD-I", though this name is a [[retronym]] applied after the introduction of OBD-II. The data link connector and its position are not standardized, nor is the data protocol. The [[SAE International|Society of Automotive Engineers (SAE)]] recommends a standardized diagnostic connector and set of diagnostic test signals.
* ~1994: Motivated by a desire for a state-wide [[Automobile emissions control|emissions testing]] program, the CARB issues the OBD-II specification and mandates that it be adopted for all cars sold in California starting in model year 1996 (see CCR Title 13 Section 1968.1 and 40 CFR Part 86 Section 86.094). The DTCs and connectors suggested by the SAE are incorporated into this specification.
* 1996: The OBD-II specification is made mandatory for all passenger cars and petrol-powered light trucks with a [[Vehicle weight#Gross vehicle weight rating|gross vehicle weight rating]] less than {{cvt|8,500|lb|kg}} in the United States. The OBD-II specification is also made mandatory for all petrol-powered vehicles with [[California emission standards|California emissions]] with a gross vehicle weight rating up to {{cvt|14,000|lb|kg}}.<ref name="Ford manual" />
* 1997: The OBD-II specification is made mandatory for California emissions diesel-engined vehicles with a gross vehicle weight rating up to {{cvt|14,000|lb|kg}}.<ref name="Ford manual" />
* 2001: The [[European Union]] makes [[#EOBD|EOBD]] mandatory for all petrol vehicles sold in the European Union, starting in MY2001 (see [[European emission standards]] Directive 98/69/EC<ref>{{cite web |url=http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CONSLEG:1998L0069:19981228:EN:PDF |title=Relating to measures to be taken against air pollution by emissions from motor vehicles and amending Council Directive 70/220/EEC |id=Directive 98/69/EC |publisher=The European Parliament and of the Council |date=1998-10-13 |access-date=2020-05-17}}</ref>).
* 2004: The [[European Union]] makes [[#EOBD|EOBD]] mandatory for all diesel vehicles sold in the European Union. All petrol-powered vehicles in the United States with a gross vehicle weight rating of up to {{cvt|14,000|lb|kg}} are required to have OBD-II.<ref name="Ford manual" />
* 2006: All vehicles manufactured in [[Australia]] and [[New Zealand]] are required to be OBD-II compliant after January 1, 2006.<ref>{{cite web |url=https://www.plxdevices.com/obdii-compliant-vehicles-s/153.htm |title=OBDII Compatibility |publisher=PLX |location=US |access-date=2019-12-25}}</ref> All vehicles in the United States of {{cvt|14,000|lb|kg}} gross vehicle weight rating and under are required to have OBD-II.<ref name="Ford manual" />
* 2007: All California emissions vehicles over {{cvt|14,000|lb|kg}} gross vehicle weight rating are required to support EMD/EMD+ or OBD-II.
* 2008: All cars sold in the United States are required to use the [[ISO 15765-4]]<ref>{{cite web |url=http://www.iso.org/iso/catalogue_detail?csnumber=33619 |title=ISO 15765-4:2005 — Road vehicles — Diagnostics on Controller Area Networks (CAN) — Part 4: Requirements for emissions-related systems |publisher=International Organization for Standardization |date=January 2005}}</ref> signaling standard (a variant of the [[Controller Area Network]] (CAN) [[Bus (computing)|bus]]).<ref>{{Cite web|title=CAN Bus Explained – A Simple Intro (2021)|url=https://www.csselectronics.com/pages/can-bus-simple-intro-tutorial|access-date=2021-11-22|website=CSS Electronics|language=en}}</ref>
* 2008: Certain light vehicles in China are required by the Environmental Protection Administration Office to implement OBD (standard GB18352<ref>{{Cite web|title=GB 18352.6-2016 – PDF BOOK Auto-delivery|url=https://www.chinesestandard.net/PDF/BOOK.aspx/GB18352.6-2016|access-date=2021-11-22|website=www.chinesestandard.net}}</ref>) by July 1, 2008.<ref>{{Cite journal |title=China's stage 6 emission standard for new light-duty vehicles (final rule) |url=https://theicct.org/sites/default/files/publications/China-LDV-Stage-6_Policy-Update_ICCT_20032017_vF_corrected.pdf |journal=[[International Council on Clean Transportation]]}}</ref> Some regional exemptions may apply.
* 2010: Start of required phase-in of the OBD-II specification to all vehicles with a gross vehicle weight rating of {{cvt|14,000|lb|kg}} and above, this was completed by the 2013 model year. Vehicles that did not have OBD-II during this time period were required to have EMD/EMD+.<ref name="Ford manual" />