Well, I've been having trouble with my heat in my truck for a while now. It used to would get burning hot to where you would have to turn it off sometimes after you got warmed up. Lately it's been so it doesn't seem to get hot at all and will eventually get warm. I finally had enough of it and took it to a shop to have them check it out. He said I needed a new water pump as it wasn't putting out much pressure. When they pulled it all apart they flushed it and all and said it had cotton like ***** in it. He had never seen that before but they got it all flushed out and he checked it with a themometer and said it was getting good and hot. When he checked it he did it on the top half or bottom half not both at the same time.


Well, I went and got it back and flipped it to where it does the top and bottom half at the same time as this is how I like it. I noticed it wasn't any better than before and still was not hot not really even warm. I called him up and he told me to check and see if the A/C line was cold. When I felt it sure enough it was ice cold. I disconnected the A/C compressor for right now since I don't need it and it seems to have helped and that line is no longer cold. He said he thinks it's doing it when I flip the switch to where it blows air both bottom and top.


We have about decided that the A/C and heat are fighting each other as it's trying to blow both at the same time. He said he wanted to check and read up this weekend and see if it had a body control module as it sounded like a relay or something had gone bad. He went on to tell me he had never had this happen but had heard about it in classes.

What I'm wondering is if anyone else on here has run into this issue and if so what I need to do to fix it? Is it an easy fix? I would like to get my heat back to normal with my A/C still connected.

 

Mode select doors, Recirc door something hard is binding sounds like, or vacuum is not getting to the controls and actuators.

Get a service manual and check wiring diagrams for the entire HVAC system.
PCM controls A/C clutch operation also.

lamens terms, - When you turn the switch/**** to AC on, the switch sends a REQUEST to the PCM saying " Hey i want AC NOW" the PCM decides whether or not to actuate the AC clutch, checking pressues on the lines, ambient temp might be too low, etc, the the PCM allows the relay to receive Ground(or maybe voltage) and completes the circuit to actuate the Clutch.
The BCM also has a say in all this argiung also, deciding on the mode doors, recirc door, and so on and so on.
Get a service manual and read up up and verify wiring diagrams and vacuum to the HVAC.
Go from there.
they check/change out the Thermostat?

 

Well, even with the A/C compressor unhooked it still isn't getting hot. The A/C line is no longer ice cold with it unhooked though. Does this sound like a heater core that he missed or something else?
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