For one, you will need exact code definitions and the
associated troubleshooting routine for tracking down the code.
Second, you will also need to determine whether there are any service bulletins that may apply to the setting of the code. Without this knowledge, you may wind up on the proverbial wild goose chase.
When the EPA embarked on its crusade of enhanced emissions testing, it appeared as though loaded-mode dynamometer tests were the only way to get the job done. Meanwhile, as states began to battle with the federal government over what loaded-mode test would be best, a silent revolution was underway — the universal application of OBDII in 1996 and later vehicles.
Soon, testing revealed that the OBDII system itself did a pretty good job of keeping tabs on the major things that affect emissions. States developed "advisory" additions to their programs, compiling data from actual vehicles for comparison to pass/fail trends. Before long, OBDII tests emerged as a reliable way of monitoring vehicles that fit into that age group.
Because of this credibility, and the fact that the vehicle population is aging, OBDII checks are gradually moving center stage as the key element of state emissions programs. Altogether, there are currently 32 programs in the U.S. that incorporate OBDII checks as emissions pass/fail criteria.
More than ever, a scan tool is a key part of your diagnostic game plan. By understanding how to best capitalize on its features and capabilities, you'll be well on your way towards putting a winning strategy in place. You'll be able to solve emissions problems and others in the vehicle's powertrain control system, ensuring customer satisfaction and the right kind of comebacks — repeat business.
Technical Editor Dave Cappert answers your questions about scan tools.
Dave Cappert examines the most important scan tool functions.