I own a 2004 Nissan Quest SL. The Ac is only blowing cold on the passenger side and warm on the driver side. About a 10-20 degree difference. I checked all the actuator doors and them seem to all be working. I tried the HVAC self test and no codes came up. MY question is can it be the Heater Pump Valve is bad? the heater pump relay? Also is the heater core suppose to be hot when the AC is on and the heat is off. The Heater core water lines are hot to the touch with the AC on. One more thing. The AC seemed cooler when I first started the vehicle until it reached running temperature, then the driver side was hot again. Any help would be great Thanks.