If you tell us what the year, make and model vehicle you have we should be able to tell you where it is. On many vehicles the condensation drain is not visible from the top. It is generally located under the hood, on the firewall, on the passenger side at the lowest point of the HVAC assembly. Probably more visible from underneath the vehicle.
To drain water from the near side sill of a 2001 Citroën Xsara Picasso, first, locate the drain holes on the sill. You may need to remove any plastic covers or trim to access them. Use a thin tool, like a wire or a small brush, to clear any debris blocking the holes. If water still accumulates, check for leaks in the door seals or window seals that may need attention.
The evaporator drain allows condensation from the ac unit to drain. When the drain clogs up water will go into the passenger floor instead.
AC condensation drain.
There is a drain on the outside firewall that is clogged.
The ac condensation drain is on the lower passenger side of the firewall.
The ac drain is plugged. The drain hose is on the firewall on the lower passenger side. ...that, or your heater core is leaking.
Are you running the air conditioner? If the drain line is plugged, it will leak water (condensation) onto the passenger side floor.
It is on the lower passenger side of the firewall.
The condensor drain tube is clogged. Find the drain line and unclogg it.
Possibly air conditioner drain hose is clogged
the heater core is leaking or ac drain is stopped up
There is no drain cock on the '07 G6 GT. The easiest way to drain is from the water pump connection at the bottom passenger side of the radiator.