Chasing an HVAC issue and I need some help here...

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Daveykid

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Hi guys, I've searched and read most related articles but my problem has a few additional elements to it so I'm not sure where to start and I'd like to be loaded for bear if I have to go back to the dealer on this one. 2015 LR4. So, here goes:

THE PROBLEM
The HVAC unit is blowing colder on the driver's side than the passenger side, but that depends. Upon initial start up and when the engine is not quite up to operating temps yet it happens and is obviously more noticeable. As the engine gets up to oper. temps and the cabin begins to warm, it is less noticeable. Once I've been driving for 20-30 minutes it is then blowing warm on the driver's side. I have yet to check the temperature difference with a thermometer between the two sides. The distribution of airflow works as it should (defroster vents, face, floor, any combination thereof) so I doubt it's the blend doors but the car is throwing two HVAC codes which I've attached.

WHAT HAS LED UP TO THIS
Recently had the car into the dealer for the coolant pipes (no leaks with the current pipes although the prior owner did have them replaced a couple years ago and I was simply replacing them as a preventative measure), had the timing chain service performed, had the trans cooler lines replaced and finally had to have the passenger side head replaced which was a whole different story. So, there were a fair amount of moving parts possibly related to a partially clogged heater core and that's what I'm trying to get at here. Was it not flushed properly? Was there soot or residue in the lines that might have been knocked loose? Is there an air bubble? The coolant levels are fine, the engine is running perfectly, no overheating issues, no noises, burps, no bubbles, no nothing I can tell.

WHAT ELSE TO LOOK FOR?
Before I go back to the dealer and point all this out to them I'd like to get my ducks in a row. The thing that is throwing me off a bit are the two HVAC codes and IIRC they've been there for a long time and do not appear to be the result of anything the dealer did so it could just be coincidental. I cannot clear the codes out with my IID tool either. They come right back. If it's a bad control module then so be it and I'll have it replaced but I don't want to do that until I've exhausted all other "dealer caused" issues. I can do basic stuff with the IID tool but I'm just not well versed enough to delve into more complex issues and possibly void any recourse I might have with the dealer at this point.

Any insight as to what else I should be chasing or doing to help eliminate possibilities would be appreciated. Thanks!
 

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Rover Range

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Usually, the temperature differences are caused by low freon levels.
 

Rover Range

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Low freon can cause the evaporator to freeze up, restricting air flow.
As the engine heats up, the evaporator can thaw out.

Not saying that's your problem, but something to look at.
 

Daveykid

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Low freon can cause the evaporator to freeze up, restricting air flow.
As the engine heats up, the evaporator can thaw out.

Not saying that's your problem, but something to look at.
Got it. Thanks! Just one more thing to add to the list of possibilities.
 

Jimmy Brooks

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I’ve got a bit of an hvac issue brewing, now that I’ve started driving the rover again I noticed that when it gets up to 96° my passenger and rear will blow warm. My driver is still cold tho. I don’t have any codes for low Freon but both my condenser and compressor have been replaced so my AC should work. Also at some points I get a faint whiff of Freon. IID tool says I’m running 120psi so I’m not sure
 

f1racer328

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I’ve got a bit of an hvac issue brewing, now that I’ve started driving the rover again I noticed that when it gets up to 96° my passenger and rear will blow warm. My driver is still cold tho. I don’t have any codes for low Freon but both my condenser and compressor have been replaced so my AC should work. Also at some points I get a faint whiff of Freon. IID tool says I’m running 120psi so I’m not sure
Could be a blend door problem if you're getting cold air but no one else is.
 

Nechaken

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I could I go about fixing or figuring it out?

Also when it gets colder out it will blow cold in the front and kinda cold in the rear

I want to say there is a blend door calibration routine in the IID tool, maybe in the service menu if I remember correctly ?
 

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