Did a search, doesn't seem like anyone else is having exactly the same issue. It's not THAT hard to live with, but...

My defogger doesn't blow as hot as the rest of the heater. I can set the controls on any combination of settings I want, and the defogger is just much colder than the air that comes out everywhere else. In order to get effective defogging I have to set it pretty dang hot and then defogger only, then it'll blow as hot as I want. I can use split level, but I have to keep it so hot that it cooks my feet. I can't take it more than a half inch from full hot when using split level or the defogger will go completely cold again even though it's still cooking my feet. So either I can be comfortable and blind, or I can cook but see.

Also, to be clear, the air flow out of each vent is fine, including the defogger. Only issue is temp. Is this just a Toyota-ism? I've had tons of 4x4s, most of the older ones have some quirk with the HVAC that you just have to learn to deal with.

 

If you have A/C it turns on when you're using defog, so that will make the air cooler.

 

Ummm, you're a contributing member with 2500 posts and all, but at first glance that seems to be a pretty stupid suggestion. Don't the defogger and dash vents and floor vents all get their air from the same place? Won't the defogger turn cold when I turn the A/C on? I'm trying to get the defogger and the dash and floor vents to all blow the same temperature here. Maybe I'm missing something.

 

the purpose of turning on the a/c while using the defrogger is to remove the moisture out of the air and defrost ur windows quicker.. so you wont have to keep it on defrost as long and cook.

 

Actually the quickest way to de-fog your windows is to run your a/c with the windshield vents going.
Running your a/c will also make your engine warm up quicker. So once you turn the heat on, you will be able to de-ice as well.

 

Yeah, thanks. I know what A/C does. I didn't say defroster. I said defogger. I just drove from Aviano, Italy to Kaiserslautern, Germany at night through the Austrian Alps in the rain. I had the defogger on medium for 12 straight hours, and it was below freezing outside for much of the trip. I'm also not talking about a minor difference in temperature, it's a big difference. A/C pulls moisture out of the air, but warm unconditioned air has the capacity to remove more moisture from the in side of the windshield than cold conditioned air.

If you look at the way the heater is set up in our trucks you will see that the side dash vents take their air from the defogger ducts AFTER they split from the heater box. There's an extreme difference in temperature between my side dash vents and defogger vents. Closing the dash vents makes no difference in temperature. This makes no sense to me unless the heat is just dissapating out of the defogger ducts before the air exits the vents.If that's what's going on I could insulate between the firewall and the defogger duct. So, I repeat my question...is this just a Toyota thing or does my truck have an abnormal problem?

 

Sounds like an abnormal problem to me..
I know my defroster blows hot air.. But i also don't have A/C.

 

Make sure the cables in the heater controls are all working properly. If they have been removed before they can get worn out and when you select a setting and move the cable, the whole cable will move a little and prevent you from getting the proper setting.

The same goes for the cable that controls the valve that lets the coolant into the heater core. Make sure its working smoothly.

I keep my heater on defrost as I dont like the air hitting me in the face. Nice and warm once my truck has heated up..

 

That's good advice. My cables are in good condition and properly adjusted, and the airflow is good. Heater core valve is open, core is hot, and the dash side vents that take their air from the defogger blow hot...but the defogger is cold. I think I'm gonna have to take my dash apart and see what's going on in there.