There's a discussion in alt.trucks.ford about code readers, and it got me thinking...why couldn't there be a small display to show a stored code, and it's definition, in every (new) vehicle? Doesn't seem like it would be all that expensive to engineer one into a vehicle, especially since a lot of vehicles (including my wife's Freestar) has a next-to-useless "information display" in the dashboard ("Door Ajar, Change Your Oil, Low Washer Fluid", etc). Seems when a "Check Engine" code is tripped, it would be helpful to have a display already there saying "O2 Sensor" or "Thottle Position Sensor."
Of course, by equipping vehicles with such an apparatus, the dealership service depts stand to lose a lot of revenue in diagnostic fees...
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