HELP: 2026 Bighorn - Defrosters barely working

[Granite Goat]

I'm a couple hundred miles into my 2nd road trip in my brand new truck (bought 2 weeks ago). It is 25° outside, light snow, on the freeway, and the top half of the windshield is freezing up on the outside. Defrosters set to full fan speed, 78°, getting hot as hell in the cab, but barely able to keep up. Feels like most air is coming out by my feet. Very little coming out by the windshield. I've tried toggling between split and full defrost to no effect. Graaah!

 

[Granite Goat]

I'm a couple hundred miles into my 2nd road trip in my brand new truck (bought 2 weeks ago). It is 25° outside, light snow, on the freeway, and the top half of the windshield is freezing up on the outside. Defrosters set to full fan speed, 78°, getting hot as hell in the cab, but barely able to keep up. Feels lile most air is coming out by my feet. Very little coming out by the windshield. I've tried toggling between split and full defrost to no effect. Graaah!

If it were any colder, I would be in a lot of trouble!

 

[KrustyKush]

Dang. Sounds like something in the HVAC vent’s isn’t right. Hoping for warmer weather for you ‘til you can get it into a shop.

 

[jkm312]

Manually move the heating system thru all of the mode settings. Floor only, floor and upper vents, defroster mode etc. It might force the blend door linkage to put the blend door where it belongs relative to the dash control settings. Sometimes the linkage in my RAM binds up it not moved thru the full range.
Hope it helps.

 

[Granite Goat]

Manually move the heating system thru all of the mode settings. Floor only, floor and upper vents, defroster mode etc. It might force the blend door linkage to put the blend door where it belongs relative to the dash control settings. Sometimes the linkage in my RAM binds up it not moved thru the full range.
Hope it helps.

Yeah, I tried cycling through the modes to no avail. Luckily it is above freezing now. I picked up a couple gallons of ice-melter washer fluid to get me by for the balance of my trip.

 

[jkm312]

As a last resort for the time being, consider pulling the cabin filter out to make it as unrestricted as possible.
Regardless stay safe.

 

[Granite Goat]

We made it back in good shape and had fair weather for the return trip. Will be scheduling a service appointment to get this rectified ASAP!

 

[KrustyKush]

Come back and tell what had to be done to fix this.

 

[Granite Goat]

Dropped my truck off at the dealership last night and got a call from them about a half hour ago.

Here's the skinny: If you have the temperature setting at anything but the maximum setting (or within a few degrees of max), air will be split between the defroster duct and the floor duct when in 'Defrost' mode. At 78+ ish, the floor duct door closes and everything comes out of the defroster vent. The technicians were stumped and learned this only after having a conference call with some other techs. I guess the behavior has been this way since 2021 (IIRC). The technician went out to the lot and jumped in a random brand new 2026 Ram and confirmed the same behavior.

I will play with this more once I get the truck back. I've never had a vehicle that operated this way and I suspect some clunky software design here. If anybody else can confirm this behavior and report back here, I would much appreciate it!

 

[Granite Goat]

I was able to duplicate what the dealer told me. Here's a video. If you've been underwhelmed by the defrosters in a 2021+ Ram, have a look!

 

[Granite Goat]

This is completely ridiculous programming. Defrost means defrost. "Don't make me disconnect the blend door motors and rig up a set of aftermarket choke cables to direct the air where I say!"

 

[pensfan]

I agree this is programming gone mad. Defrost should be defrost. If it has to be on 80 degrees that is plain stupidity. I wonder how many unnecessary service visits and wasted customer hours were caused by this idiotic 'feature'. If this is how it works then it should be mentioned in the owners manual.
I ordered a new Ram last week. Stuff like this is making me think I should keep my '16 Ram that runs great and where defrost is just that.
The other thing with the HVAC system is they took away the fan control knob and it was also the on/off button for the system. A knob is way easier to adjust fan speed than a toggle switch. The on/off is now an icon on the screen. More idiotic thinking.

 

[B33P33]

Fwiw I was taught when growing up to have the heat slider on max heat and a/c on for defrost. This was back in the 90s before electronic. All manual sliders. So the thinking of max heat for defrost actually works with my brain. But I can see how this is maddening to others.