Hi. I have a Dodge Ram 1500 V8 Mag 5.9L and the temp sector is not working. Here are some facts about it:
1. Temp Selector **** turns freely with no issues.
2. The blend door does not thump when I turn the selector all the way cold to all the way hot.
3. This model is cable controlled, and from what I see the later models have a powered motor with a faulty plastic tab that likes to break. My model does not have this motor under the dash.
4. The heater core lines are hot going in and out, so I believe it is functioning normally.

I am not a mechanic and have no idea where how to preceded. Need help on fixing this problem, because it's getting cold in Missouri.

 

Unfortunately, the actuator for the blend (temp) door, is on TOP of the heater box. If you feel around on the bottom, you can see the axle for it sticking out, put your finger on it, and turn the temp **** from one extreme to the other. Does the axle actually move?

 

Thanks for the reply! From what I can tell there is no movement, at least if I'm looking at the right thing. There is a little shaft recessed into the plastic hvac body near center of the left side dash. I'm assuming this is the axel you are referring to.

 

Should be right above the trans tunnel, just to the passenger side a bit. if it doesn't move when you turn the ****, pull the HVAC control head, make sure the **** is actually moving the cable before tearing out the dash.

 

I am not seeing or feeling any movement under there. I pulled the control panel. Everything looks ok behind there. The switch seems to be pulling the cable just fine.

 

Time to pull the dash, and see what's happening up top.

 

Had a feeling, Lol! This is my primary vehicle right now so before I great down the dash I need you know what parts I might need to replace or should replace.

 

Won't know until you get in there...... but, since you are going to be in there....... heater core, evap core, while the box is apart, make sure the blend door is well secured to the axle.... I am not sure what sits on top there, that the cable actually operates..... You can download a parts manual for your truck, and take a look at the nice pictures... give you an idea of what you might need. And chasing parts BEFORE it is scattered around the garage really isn't a bad idea here..... as some of them may not be available any more.

 

If you remove the stereo you can see it if i recall. I had my cable come off the mount on the box. I tried to fix from there but it wasn't happening so had to partially remove the dash enough to reach it.

 

Thank you both for your replies! I am sorry it took me so long to hop back on here. I have yet to have time to treat into the dash. I did discover a temporary ghetto fix. I took a pair of pliers and rotated the blend door axle over to heat and it works great. Interestingly enough, when I turn the truck off the blend door snaps back to the temp position the selector died in. What do you think is causing this snap back? I am by no means an expert on vehicle hvac systems, but logically I think if the door actuator motor was bad, then it wouldn't move back. If the blend door was broken at the motor, then it wouldn't move back. So what's going on there?