My air works but the heater only works after hearing the ticking sound. Also, the left passenger floor is wet. What is happening?

Sounds like the a/c drain is clogged up you need to look on the firewall near the bottom behind engine pull drain stop of and clean it out and see if that takes care of your problem .

sounds to me the heater box needs replacing. could be because of a leaking heater core. are you havings to add coolant? wet floor mats on pass side? the knocking you are hearing is more than likely the blower fan hitting on the plastic molding because of a faulty bearing in its driveshaft.

does you vehicle have the dual climate control on each side?? where you can choose how hot your air is, and the passenger can set theres?? when the floor gets wet thats usually a positive sign that the heater core is bad.. im not exactly sure how your lexus is set up, but id say either you have a heater core bad, or the blend door for the passengers side is stuck.. thats only possible though if there is indeed dual climate controls.. hope this kinda helps

If you've been using your air conditioner during this time, and it hasn't rained at all, then the small drain at the bottom of the a/c evaporator core may be plugged. When you use the a/c to cool the car the evaporator coil [located next to the heater core in the ductwork under the dash] is very cold and moisture from the hot humid air condenses on it as a result. This condensation dribbles down the core and accumulates in the plastic housing under it where it should then drain out a small hole and drip onto the ground. If the small drain gets plugged, which happens quite often, then the water fills up the housing until it overflows and then runs out and soaks the carpet on the front passenger side. The drain is located on the engine side of the firewall, passenger side, down low where the firewall begins to curve under. Usually a puff of air will clear the clog and the drain will work fine again. If the carpet is really wet it would be a good idea to remove it and get everything dry again as it tends to get pretty smelly if left wet. One last note: usually a leaky a/c unit will only make the passenger side carpet wet unless it's been leaking for a long time while a leaky windshield seal can make both sides wet depending on where it is leaking. Good luck, hope this helps you out!

there is a leak because the foam has disintegrated, or the seal has broken open down by where the feet of the passenger is. Rust stains tell me that the leak may be caused by a break in the body somewhere.

Try spraying expanding foam in the area between the plastic and the metal parts to try to seal out moisture from coming into the passenger compartment.

did you drive in the rain before and this not happen. if you used the heater,or defrost,then sounds like heater core is leaking.

liquid on passenger floor is most likely your heater core needs replaced

Check the heater core unit located underneath the dashboard on the passenger side of the vehicle. Even though your car's antifreeze is red, it may appear to be clear when there is only a small amount present. Was the liquid in the vehicle sticky and have any smell to it?

sounds like two problems. the ticking sound is probably a broken blend door stop. the wet floor is probably a bad heater core, both require dash removal.

Clean out the drain tube .