Hello everyone newbie here.
I have been reading alot of post and thought I had the problem fixed. Here is the problem, 2003 s type 4.0 V8 the outside vents are blowing hot air and the middle ones are blowing cold while on A/C. I replaced the heater valve and while it was at idle they all were blowing cold. As soon as I went down the road the low coolant light came on which I had been waiting for and then the hot air came out the side vents again. I'm not sure if the ccm needs to be replaced now or what. Can anybody give me some help.

 

Low coolant should not happen - vital to fix it very soon and try not to drive for fear of overheating the engine, which may not show up on the gauge due to the low coolant. Be aware that an overheat would likely ruin the engine.

Did you bleed the coolant with heater on max?

 

I think you mean 2002 4.0? or a 2003 4.2?

Yes give the car a few hot and cold cycles to work the air out.

Yes you might have a damaged CCM but do some reading on that before getting it looked at. If you don't have navigation the CCM is kind of buried behind the center stack. If you have navigation the RCCM is very easy to get at after removing the glove box.
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