It is completely possible to fail the smog check because a vehicle is not driven enough. This usually happens when a vehicle's battery level gets so low that the engine control unit Emission Monitors are erased. If you had to jump start your car or replace the battery, this is more than likely what happened. Driving your Jeep Cherokee through a drive cycle will allow it to complete (make ready) the emission monitors needed to pass the smog check. Typically driving for a few hundred miles over the course of a week, in both highway and city conditions is enough to get the emission monitors to run.
posted by SmogTips Support
