I have full heat only regardless of what temp adjustment knob is on and regardless of whether AC is turned on or not. I also have hot air coming through the vents when fan is turned off but fresh air is selected. It stops when I turn recirculating air switch on. I have already had the console knob checked (and replaced microswitches) and I cleaned the temp sensor under the ignition and made sure the hose was connected. (I think that would only matter if set to Auto but I checked it anyway.) Most problems I read about seem to be weak or not heat but mine is obviously the opposite. If it is the blend door how much of a PITA is this going to be? I may drive around all summer with the windows open before I attempt to pull the dash!
Does this sound like a blend door issue? (1 Viewer)
- Thread starter Carnut68
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one time i had the cowl under the steering wheel off installing some wiring, and i had that weird temp sensor w/ the hose on it disconnected. I drove my 04 LX470 with that temp sensor disconnected, and all i could get out of the system was full-on heat. As soon as i plugged that back in, i was able to get AC again. So make sure that temp sensor is good
With the car off (so it’s quiet) and the ignition to ON, if you adjust the temperature do you hear any whirring noise coming from under the dash? That’s the sound of the blend door actuator.
Seconding what excessive said above. If your cabin temp sensor is unplugged you will only get full hot, unless you put it all the way to max cold then it will blow cold air.
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So yes I do hear a slight noise when I adjust the temperature knob, whether it sounds like it should or not I don't know but it is trying to do something. And the cabin temperature sensor is definitely plugged in.
I had a similar issue. You can try the AC diagnostic - hold the auto and recirc/fresh air buttons and turn the ignition to "on". If there's a air mix servo issue it will show up as code 41 on the climate/time panel (at least on my 06 LX470). I've discovered that mine consistently happens if it's cold out and the car sits overnight. Rarely in the summer. If I run heat to the foot well for an hour or so it starts working...I'm guessing the grease in the servo is old and gets gummed up when it's cold. Total guess.
Anyway, apparently it's possible to replace the air mix servomotor without pulling the entire dash. I have the part (87106-60120) but haven't attempted the replacement. If it is even possible it's going to be a tight squeeze.
Anyway, apparently it's possible to replace the air mix servomotor without pulling the entire dash. I have the part (87106-60120) but haven't attempted the replacement. If it is even possible it's going to be a tight squeeze.
