Why does the heat not work in the second & third row seats? I've followed the troubleshooting tips - coolant level is good, blower/fan is working, tried the thermostat changes. Heat is supplied to the front seats but not to the back of the car. I'm guessing it was this way with the A/C also. The passenger floor is wet, but thought that was caused by weatherstripping failure because it is most notable after rain. Have not noticed the sweet smell of coolant.

Can you help, please? Thank you!