He did not say. If I recall correctly, he stated that FCA was aware of an issue, and his team was working on a solution. A short time later, he posted that they did not foresee a solution anytime in the future. I've looked for his posts, and I can't find them. I imagine FCA had the posts taken down, or forced him to take them down.
My suspicion, is that there is a design flaw in the HVAC box, in the dash. Some trucks have the bad box, some don't. The only solution would be to tear the dash apart to replace the bad box. This is a very labor intensive job, which is probably why FCA won't admit to it.
There was a gentleman on this forum that had the same HVAC issues as everyone else. His dealer got the authorization to tear his dash apart and replace the HVAC box. Long story short, the dealer's service techs ended up destroying his new truck. Again, probably why FCA doesn't want to offer a fix for the problem. His name was Albert, and he stopped posting back in Dec. Not what ever happened with his truck. His thread about his HVAC, is a very good read. Here is the link below:
Hi All, My 2019 3500 is having an issue where the AC is coming from the defrost in all modes. To clarify, when in vent mode it seaps from the defrost and constantly fogs up the windshield, the longer i sit or drive the worse it gets. If I turn the wipers on it gets worse much faster. If I put...
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