I have a 2009 Kia Optima and the air conditioner is leaking water on the floor board on the passenger side

Check fuses and relays. It could also be the switch unit or even the wiring where it goes from door to the body.

Fuse Box Diagram KIA Optima (MG; 2007-2010)

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The fuse box is located behind the cover on the driver's side of the instrument panel. The location of the fuses in the passenger compartment: KIA Optima (MG; ...

KIA Optima (2005 - 2010) - fuse box diagram - Auto Genius

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May 26, 2016 - KIA Optima (2005 - 2010) - fuse box diagram. ... (2005 - 2010) - fuse box diagram. Year of production: 2005, 2006, 2007, 2008, 2009, 2010 ...

Kia Optima II (2005-2010) Fuse box diagrams & schemes

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Kia Optima II Fuse box. Years of production: 2005 2006 2007 2008 2009 2010. If you are into cars, you must have heard about the brand Kia Motors.

Fuse Box 2007 KIA OPTIMA LX 2.4 - FreeAutoMechanic ...

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Aug 31, 2016 - The relay is located in the Under Dash fuse box and the blower motor fuse according to the diagram. Looking at the engine compartment fuse ...

May be air conditioner stopped up running in grooves on front passenger side to back floor board

your heater core is bad they leak when they go bad youll have to replace its under/behind the dash

evaporator and heater core drain tube stopped up.

Sounds like the outside drain is stopped up.
There should be a tube coming out of the firewall near the passenger floor.

This could be a sign the heater core or hose has gone bad and is leaking into the cabin since it is located inside the dash ifs its antifreeze it will have a sweet smell.
It could also be your AC condenser, or possible window seal.

crawl under car and look for a hose on the passenger side stick something up it carefully,, if not you will have to tear stuff apart to get into the area of the condensor

Most cars have the air conditioner drain on the passenger side just in front of the fire wall , if this becomes clogged it will back up and run out in the area you indicated. Look for the drain hose and make sure it is not kinked or plugged!

The problem you describe could be from condensation. On very humid days, I have seen some condensation from auto air conditioners blow through the ducts. If you run your A/C in the heat/defrost mode (it probably comes on by itself when you run the defroster), that could happen, and the water could be leaking down through the heater vent. It could be a sign that you're A/C unit is low on refrigerant, in which case, you'd need to get the system serviced.

A leaking door seal on the passenger's side could also cause that, but only if it was raining. If I assume that this is happening when it is not raining, the A/C is the only place water could be coming from. The only other, remote, possibility is windshield washer fluid, but you would probably notice that by its odor.

Hope helped (remember rated this help).

are you running your ac cause that sounds like the condensation drain tube

I have a 2006 Fusion with the same issue and I fixed it for less than $2. There is a drain tube that goes from the passenger floor board out through the firewall to allow water to drain under the vehicle. However, water can travel along the underside and seep back into the vehicle. I went to a hardware store and bought a few inches of 5/8" tubing. I simply slipped this onto the drain and the water now flows down the tube and safely away from the interior of the car. Been dry ever since.