It probably has a leak in the heater core.
check sunroof for leakage
better check your heater core.
You probibly have a bad heater core.
windsheild leaks
If it's the front passenger side ,I would say your heater core is leaking .
If it is wet with engine coolant you have a leaky heater core.If it is wet with water you have a plugged AC condensation drain.
Water on the passenger side floor would be a plugged up AC drain. The drain is located under the hood, at the lowest point on the HVAC box on the firewall. However if the floor is wet with engine coolant, the heater core is leaking.
Well, if your experience is anything like mine, your heater core is gone. Take it to the shop.
Check for a sickly sweet smell. The heater core is probably leaking coolant into the floor. The core is not repairable but can be replaced.
I had the same problem with our 99 venture we found out that the drain hose for the A/C had come off and was draining inside the van.
because at the bottom of the door its is a black plug pull it out and all the water will drain out of your door
Is it blood, oil, water, or urine?