This has me baffled. I have an '06 Sport model, no navigation. I am not getting heat from any vent (floor, dash, window) regardless of temperature setting. So, even in "Hi" I do NOT have heat.

Here's what I've done:
-Verified heater control valve (on firewall) moves through range of motion. It operates smoothly from closed to open as the temp is set from low to high.
-Verified driver and passenger side mix control motors are turning the plastic gears through full range of motion. I did not remove the motors, but they clearly drive the gears without issue.
-Ran a DTC test and got no codes.
-Ran a sensor input test and everything makes sense. Here are the results:

In Hi (heat) mode:
Sensor 1, in-car temp: 25C
Sensor 2, ambient temp: 25C
Sensor 4, engine coolant temp: 86C
Sensor 5, evap outlet temp: 25C
Sensor 6, dri mix motor: 96% (high value indicates warm air)
Sensor 7, pass mix motor: 96%
Sensor 9, vent temp air out: 58C

In Lo (a/c on) mode:
Sensor 1, in-car temp: 25C
Sensor 2, ambient temp: 25C
Sensor 4, engine coolant temp: 86C
Sensor 5, evap outlet temp: 8C
Sensor 6, dri mix motor: 6% (low value indicates cool air)
Sensor 7, pass mix motor: 6%
Sensor 9, vent temp air out: 14C

So, I get no codes, all sensors seem correct, the operation seems correct and sensor 9 shows that there's heat in the box. Why the heck can't I get heat out the vents? All help is appreciated. I'm out of things to try.

Thanks,
Rich

 

Maybe I've figured something out. Sensor 9 (vent air temp out) reads 58-64C all the time, regardless of engine temperature. So, with a cold engine (engine temp 35-40C), Sensor 9 was still reading 60C. So, that sensor is clearly out to lunch.

Furthermore, with the car up to temperature, the hose from the engine to the heater control valve is cold. Is that a good indication the valve is shut/blocked? (even though I can see the cable move the valve)

 

Yep, sounding like the valve is bad. They have been known to phail:

https://acurazine.com/forums/3g-tl-2004-2008-93/f-167-heater-water-coolant-control-valve-diy-747304/

 

I had that same problem few years ago. The lever on the heater control valve was broke and not connected to the flap inside that box.
So yes the cable would move but the lever wasn't opening or closing that valve.
Replaced it and all is well.

 

I'm experiencing something similar. When the heat is full blast I get heat for a little bit, then when I come to a stop or slow down it goes cold again. coolant levels are good, system is burped and air free.

thinking valve or possibly water pump, car does run warmer than usual but not overheating