That is the plug where the dealer or your repair shop plugs in to
diagnostic codes from your car. Also if you have it in your state, the
emmission test facility will plug their computer into that plug to see if
your vehicle has any stored problem codes.
Scott
> There is a gray plastic plug (female) to the left of the main console,
> basically hidden unless you get down on your hands and knees. It is circled
> in red in the picture shown here:
> http://herb.thetysons.org/images/Plug-in-2000-Odyssey.JPG
> Can anyone tell me what this plug is for?
Looks like the OBD-II connector.
You can plug in a gadget here to look for various dignostic codes.
Places like AutoZone will do that for free, so they can sell you the right
replacement part for certain codes.
You can also plug in a ScanGauge, a sort of aftermarket trip computer.
http://www.scangage.com/
This looks like the plug:
http://www.scangage.com/big_with_key.jpg

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Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8,-122.5