I just replaced the Blend Door Actuator on my 1999 Dodge Ram 1500. Here is the problem. I had it on heat and it worked great, I turned the temp control down to cool and it blended on down as it was supposed to, BUT when I turned the temperature control all the way back to hot it won’t go, it stays at the cool setting. Is it a temperature control dial issue or have I done something wrong?
thanks

 

I think there is a specific installation procedure for those. If you don't have one already, grab the service manual for your truck from here.

 

No sir I bought a coupler from Heattreater and followed all instructions to a T. The computer resets it according to them, no adjustments necessary. I saw somewhere that if I remove a certain fuse for 30 seconds it resets the computer or something. But I can find where I read this.

 

Ok, theoretically, you can re-zero it by turning the temp **** to the mid position. (middle of travel, or, pointing straight up....) Disconnect the battery for a few minutes... I turn the headlights on as well, to make sure everything gets drained.....then turn them back off. Turn the ignition to "on", and the blend door actuator *should* reset itself....... Should..... That assumes that the blend door moves freely though.

 

Thank you, I will try this later on today. I’ll let you know how it works out.

 

ok I tried this. When I turn to full heat it works as should, then I turned it back to full cool and it works as should. BUT……when I go back to full full heat it stays on full cool same as before. Any other suggestions??

 

I'd remove it and eyeball it. When NOT connected does it move as it should? Also can you freely cycle the blend door by hand?

IOW, is it an issue of the motor simply not moving when commanded, or being unable to move due to obstruction or other?

 

lol I just did that. It did this before I changed out the actuator, the reason I changed it because I thought it was bad. Yes I can manually open and close the blend door manually. The actuator turns in both directions when not installed. Could it be the heater control panel itself? That’s the only thing I can think of. If I remove the fuse for blower motor, actuator is on same fuse, it will go back to hot until I turn it back to cool. It’s about to get on my nerves like a ex wife! lol

 

What does the coupler between the actuator, and axle for the blend door look like. They are known for cracking, and then you get unreliable behavior.

 

He said he put in a Heater Treater which is a replacement metal coupler.

OP, if it moves in-hand when commanded I'm guessing your blend door is partially broken and thus misaligned.

Can you shove the pin attached to the door up/down or slop it around? At the risk of stating the obvious, think about the front door on your house -- if the hinges are sloppy you may be able to close it sometimes and struggle others.