Lean down and look underneath of your dashboard so that you can see your fuse panel on the left hand side of the steering wheel without removing your fuse panel. There should be a small gray plug in to the left side of that. I just installed a device on my own 2000 civic. Hope this helps.
The 2003 Honda Civic OBD 2 port is behind center console
The 1997 Honda Civic OBD 2 port is on drivers side,connector faces down
The 2004 Honda Civic OBD 2 port is behind kick panel; above accelerator pedal
The 2001 Honda Civic OBD 2 port is on lower right edge of dash; behind console trim
The 1996 Honda Civic OBD 2 port is under dash on left side connector faces down
The 1996 Honda Civic OBD 2 port is on driver side,connector faces down
Civic 91 LX still dont have Obd Port on it. Obd is Usually use for a car with ECU (electronic control unit).
The 2004 Honda Civic OBD 2 port is behind kick panel; above accelerator pedal
The 2007 Honda Civic OBD 2 port is under driver side dash next to center console
The 2001 Honda Civic OBD 2 port is on lower right edge of dash; behind console trim
The 2006 Honda Civic OBD 2 port is under driver side dash next to center console
The 2006 Honda Civic OBD 2 port is under driver side dash next to center console