If the liquid is coolant, your heater core or line may have sprung a leak!
This happened to me, two huge puddles on my passenger side floor mat twice in one day. I looked up below the dash and found the hole it was dripping from. I found a nearby hose sticking out about two inches that wasn't connected to anything. Reconnected and problem solved. Just a disconnected hose.
If the hose is still connected it may just be plugged, you can free it up by probing it with a piece of wire.
According to the Honda Floor Mats website, there are four different floor color mats available for the Honda Civic Sedan. The colors that are available are grey, black, brown and beige.
Pump the pedal to the floor and then screw on the cylinder.
Depends on the year of the Civic. Will be on the floor next to the drivers seat on 2001-05 Cvic.
The computer is located under the passanger floor mat.
Condensation from air conditioning?
the module is to the right of the gas peddle,bolted to the floor.
Can be a leaking heater core if the fluid taste sweet. Can also be the drain tube for the windshield cowl is stopped up.
Most likely this is a weatherstripping problem, check the seals around the door and windows for damage or severe cracks. If there is coolant in the pooling, then you have a heater core prob.
Leaking windshield or clogged windshield cowl drain lines.
A Honda Civic hood latch is usually located underneath the dashboard on the left of the driver. In some models, it may be located on the floor by the drivers seat.
The SRS control unit is found behind the center console on a 2002 Honda Civic. Removing the center console will show the unit which will be mounted to the floor of the car.
If you are in the UK try Halfords, they sell them pretty cheap, also Honda Civic's web-site will sell them but might be over priced. Although your locale car parts / accessories will sell them cheaply.