More than 20 years ago, automakers and the EPA developed the standard that we know today as OBDII. This standardized many of the onboard emissions protocols and codes and allowed states to perform onboard emissions testing. For technicians, it opened a whole new world of diagnostics. As time passed, even large trucks and motorcycles adopted this same way to test the emissions status of a vehicle.

As part of OBDII, Mode$02 for the logging or freeze frame data was created. This diagnostic protocol saves data PIDs and information when a code is set. In 1995, freeze frame gave technicians a powerful diagnostic tool that was previously only available on expensive factory tools.

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