User guide

AutoEnginuity ScanTool User Guide 3
wide variance in both fault codes and the equipment necessary to
interpret them.
The EPA stepped in and created an extensive list of procedures and
standards based on the findings of the SAE and ARB. This list
resulted in the second generation of onboard diagnostics, the OBD-
II. By 1994 manufacturers were to implement OBD-II unless a
waiver was granted. Almost every manufacturer applied for, and
received, a waiver. However, in 1996 all new passenger vehicles
were required to be equipped with OBD-II—without exception.
The idea behind OBD-II is simple: in vehicles manufactured in
1996 or later, no matter who the manufacturer is, there is a standard
set of fault codes that use a standard tool to interpret them.
OBD-II Today
As the years went on, some manufacturers improved upon their
implementation of the OBD-II. In addition to the basic standard,
they implemented optional support (i.e., more sensors). Some
manufacturers (Ford, GM, etc.) didn’t stop with optional support,
but saw the utility in going above and beyond. These enhanced
implementations give access to more sensors and even more
descriptive fault codes. Although they are vehicle specific, their
value can be easily seen by any service shop that specializes in that
make, or a tuner that wants to wring every ounce of performance
from his vehicle.
The Future of OBD
OBD-III is already in development. What the new standard
will contain is still a matter of speculation, but some things are
certain: 1) more advanced support for sensors will come about; and
2) faster interfaces (to move data back-and-forth) will be
implemented. Some speculation is that vehicle transponders will be
part of the standard. The transponders would be used to locate the
vehicle in the case of faults or non-compliance with EPA
regulations; and, possibly, whether or not you are in compliance
with local traffic regulations. Whether consumers will ever allow
their congressman or congresswomen to implement such a standard
will have to be seen.