you probably need a new thermostat, remove the one you have then get a new one asap.
Sounds like heater core is leaking
Yes, most likely if its under the passenger side dash its your heater core. Not hard to fix. Good luck
The heater core has failed and is leaking engine coolant.
If it is water it is probably the condensation drain plugged up with crud. If it is engine coolant it is probably the heater core leaking.
In the passenger cabin, under the dashboard on the passenger side.
it is under the passenger dashboard, the entire dashboard has to be removed.
On the undercarriage, under the rear passenger door. It will be directly in front of your fuel tank.
your windshield seal has failed
I believe it to be the airbag (passenger) making that humming sound
Yes, under passenger side of the dashboard.......
Under the dashboard in the passenger side
either ac drain is clogged or heater core is leaking