The History of On-Board Diagnostics (OBD)

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The 1950s in America began with approximately 25 million registered vehicles on the road.  By 1958 that number had more than doubled to over 67 million cars registered in the USA.  With this many vehicles on the road, smog was becoming an increasing problem.  By the early 1960s the state of California began introducing laws to address and attempt to rectify the smog issue.  This movement for clean air started to catch on by the rest of the USA and by 1968 the entire country started to require On-Board Diagnostics (OBD) as a requirement to help reduce air pollution from on-road vehicles.  In 1970, the first Clean Air Act was enacted by congress and became the foundation of the Environmental Protection Agency (EPA).  By 1981, the EPA required that all vehicles must have diagnostics to monitor sensors related to engine operation.  This is how the first check engine light was born.

Driving through the smog in the city of LA (1973)

By 1988 the California Air Resource Board (CARB) required all new vehicles sold in California to have some basic OBD capability.  This is what we now refer to as OBD-I.  OBD-II, which was a major improvement over OBD-I and standardized many aspects of OBD, was issued by CARB in 1994 and required on all cars sold in California by model year 1996. 

View overlooking the Observatory and downtown Los Angeles (2019)

 OBD has come a long way since its inception in the early 1960s.  Systems are more intricate but also much more accurate. The standardized tools that have been developed for OBD allow technicians to easily diagnose and repair vehicles using Diagnostic Trouble Codes (DTC).  Data shows that OBD is helping to reduce air pollution and clean up the smog in California.  You can talk to almost anyone from Los Angeles that was around during the 1960s and they can attest that the air quality has dramatically improved over the last 60 years.