it seems like when it gets cold out my heater never blows out any heat even after
driving all day? I can't find any specs on the heating system to see if there is a valve under the dash thats stuck shut. I've never had any cooling system problems so I don't think its a problem on the engine side. This is my first RX so I wasn't sure if this was a common problem

 

my fd does the same thing, i would like to know this as well

 

That's a tricky one. I haven't really delved into the heater system yet on the FD, so I don't know a lot about it. Typically you have a water valve that opens to let engine coolant circulate through the heater core, and a flapper door that moves to duct fan air through the heater core.

You might be able to see the actuators move under the dash as you change the settings. Might want to see if an actuator is jammed up or unplugged.

Dale

 

You only get heat in the "floor only" or "floor + defrost" positions. The upper vents do NOT put out hot air, no matter what temp setting you use. This is explained in the owner's manual.

As far as heat output goes, the heater is probably not going to keep up with sub-30 degree days very well -- guess what, it wasn't intended to either.

If the above doesn't remedy the situation, then there may actually be a problem with your heater core or ventilation system.