Actron AutoScanner® Plus CP9580A - Manual (Page 22)

Getting Started
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SAE Publications
SAE has published hundreds of pages of text defining a standard
communication protocol that establishes hardware, software, and
circuit parameters of OBD II systems. Unfortunately, vehicle
manufacturers have different interpretations of this standard
communications protocol. As a result, the generic OBD II
communications scheme varies, depending on the vehicle. SAE
publishes recommendations, not laws, but the Environmental
Protection Agency (EPA) and California Air Resources Board (CARB)
made many of SAE’s recommendations legal requirements that vehicle
manufacturers were required to phase in over a three-year period.
Beginning in 1994, vehicles with a new engine management computer
( about 10% of each manufacturers fleet ) were supposed to comply
with OBD II standards. For 1995, OBD II systems were to appear on
about 40% of the new vehicles sold in the United States. Some of the
1994-1995 OBD II systems were not fully compliant, so the Government
granted waivers to give manufacturers time to fine-tune their systems.
Beginning in 1996, most of the new vehicles sold in the United States
were fully OBD II compliant.