Front Defroster Functionality

[Kungfubhuda]

So, I went to run an errand in the snow storm last night, and when I hopped back in my truck, the windshield had fully fogged up. I put the defroster on high, but it didn't work on driver side 1/3 portion of the windshield. When I put my hand over the vent, it was blowing full air out of the center, but pretty much nothing out of the slots on the driver side.

Air is supposed to come out at full power across the width of every slot, correct?

 

[RamCares]

So, I went to run an errand in the snow storm last night, and when I hopped back in my truck, the windshield had fully fogged up. I put the defroster on high, but it didn't work on driver side 1/3 portion of the windshield. When I put my hand over the vent, it was blowing full air out of the center, but pretty much nothing out of the slots on the driver side.

Air is supposed to come out at full power across the width of every slot, correct?

Hi Kungfubhuda,
We're sorry to hear about this! We suggest having your dealer look into this if it continues to happen. You may also send us a private message if you would like any additional assistance once your truck is at the dealer.
Lydia
Ram Social Care Specialist

 

[riccnick]

So, I went to run an errand in the snow storm last night, and when I hopped back in my truck, the windshield had fully fogged up. I put the defroster on high, but it didn't work on driver side 1/3 portion of the windshield. When I put my hand over the vent, it was blowing full air out of the center, but pretty much nothing out of the slots on the driver side.

Air is supposed to come out at full power across the width of every slot, correct?

Not necessarily, it depends on what mix function you have set. The vents on the outer most left and right of the dashboard are "fresh air vents", and are always "on" at least a bit, to allow airflow into the cabin. When the mix is set to "Vent" (all the front dash vents), the fresh air vents are included in that mix. Otherwise, they get bypass air and do not necessarily flow based on the fan speed. When you have the front defrost selected, the windshield vent is the priority.

I set the front defrost, and rear defrost, and then push the auto button once. It keeps the front defrost on until it thinks its not needed and then returns to normal function with the auto setting.

 

[Polaris Man]

My drivers side portion of windshield fogs up sometimes too, I have noticed that the fan blower speed (may have something to actually do with vent door operation) changes over time on its own (note that I never use auto) and generally keep it at 7 fan speed on the ride to work ( -20 and lower most mornings) anyways the amount of air coming out of the defrost vents decreases while the amount coming out of the foot warmers stays the same or slightly increases ( I keep it on defrost/ foot warmer). It will switch back to "normal" amount of air coming from defrost vents on its own eventually or can be reset by turning off the truck and turning back on, which seems to fix most of the little electrical gremlins I have had.

 

[Rich]

I'm finding strange things with the defroster and even the climate control.

1) The defroster won't come on when I remote start the truck when it's well below freezing out, yet the rear defroster does come on. I check the airflow and there is some to the windshield, but it's not at full defrost levels.

2) if I get in the truck when there engine is warm, have climate in Auto mode, then dial the temperature from 72 F to 84 F or Hi, the fan will not go high, it stays at a low fan speed so it takes the truck a long time to raise the temperature. Yes, I can manually put the fan on high, but why won't Auto mode bring the fan speed high? It seems to select high fan speed to warm up the truck from a cold remote start, so I'm confused why it won't go to high fan speed when we want to warm up quickly.

 

[BiLlYDeE]

Unless I’m missing something, these trucks do not have auto climate control. If this is the case, it’s strange as this is old technology. (My 1994 and 2000 Lexus sedans had climate control.)


I have to ensure that my temperature is set to 70+ when I come home each night so that it blows warm air the next morning when I remote-start my truck because it doens’t automatically adjust the temperature or fan speed.

 

[Rich]

Unless I’m missing something, these trucks do not have auto climate control. If this is the case, it’s strange as this is old technology. (My 1994 and 2000 Lexus sedans had climate control.)


I have to ensure that my temperature is set to 70+ when I come home each night so that it blows warm air the next morning when I remote-start my truck because it doens’t automatically adjust the temperature or fan speed.

My Bighorn with level 2 options has Auto climate control.

 

[SpeedyV]

Unless I’m missing something, these trucks do not have auto climate control. If this is the case, it’s strange as this is old technology. (My 1994 and 2000 Lexus sedans had climate control.)


I have to ensure that my temperature is set to 70+ when I come home each night so that it blows warm air the next morning when I remote-start my truck because it doens’t automatically adjust the temperature or fan speed.

Of course they do...see the "Auto" button on the left side of your 12" screen (or your owner's manual, or the UConnect Comfort settings).

However, the system responds slowly; it takes several minutes for it to 'react' upon initial vehicle startup and behave as we would expect. This has been discussed in previous threads.

 

[Kungfubhuda]

Thanks for the helpful info guys. I did reach out to my local dealer, and they mentioned that the air does come out a little weaker on the sides, and that maybe I just had a bunch of moisture in the cab from all of the snow getting tracked in.

Worst case scenario, maybe I can rig something to the dash to redirect some of the center air toward the driver's side. For now, I'll just try the auto setting and try to knock as much snow off of my boots as I can before getting in.

 

[riccnick]

Mine functions as expected, however, I will add, that most newer vehicles do not always use the HI fan speed when on AUTO setting due to noise and perceived "comfort levels" of too much air blowing on the driver and passengers of the vehicle. The truck knows that it only needs to move a certain volume of air to achieve the desired temperature, even on HI, so if it doesn't see the need for the higher fan speed, it won't use it.

The truck is not set to automatically use only front defrost when remote started. It uses the defrost / floor mix setting to warm the cabin and defrost the windshield. If you want full defrost, you have to press the button when you get in.

 

[BiLlYDeE]

Of course they do...see the "Auto" button on the left side of your 12" screen (or your owner's manual, or the UConnect Comfort settings).

However, the system responds slowly; it takes several minutes for it to 'react' upon initial vehicle startup and behave as we would expect. This has been discussed in previous threads.

When I press “Auto” on my truck, it kicks on the fan high speed immediately on a cold start with cold air. If this were a true auto climate control system, the fan wouldn’t kick in until warm air was available and then the fan would gradually kick on.

 

[SpeedyV]

When I presse “Auto” on my truck, it kicks on the fan high speed immediately on a cold start with cold air. If this were a true auto climate control system, the fan wouldn’t kick in until warm air was available and then the fan would gradually kick on.

No, it would do that if it were a better-programmed intelligent system. It eventually sorts things out, as I stated previously and has been discussed on previous threads. We’re all hoping FCA will update the control logic to respond appropriately when the vehicle is first started.

 

[BiLlYDeE]

No, it would do that if it were a better-programmed intelligent system. It eventually sorts things out, as I stated previously and has been discussed on previous threads. We’re all hoping FCA will update the control logic to respond appropriately when the vehicle is first started.

Agreed. That would be nice for it to operate as expected. Unfortunately, mine does not eventually sort things out, as I stated previously and has been discussed on previous threads.

 

[SpeedyV]

Agreed. That would be nice for it to operate as expected. Unfortunately, mine does not eventually sort things out, as I stated previously and has been discussed on previous threads.

I looked at your post history but was unable to find any previous threads or posts above from you that indicated the system didn’t eventually settle in. If that’s what you’re experiencing, you should take it in for warranty service. For reference, here’s a previous discussion on the (lackluster) automatic climate control performance at startup:

https://5thgenrams.com/community/th...an-speed-not-accounting-for-engine-temp.3668/

Another one:

https://5thgenrams.com/community/threads/climate-control-on-auto-randomly-shuts-down.1712/

And a couple of others on A/C performance in general:

https://5thgenrams.com/community/threads/a-c-performance.605/

https://5thgenrams.com/community/threads/air-conditioning-performance.990/

Good luck with your issue.

 

[riccnick]

When I press “Auto” on my truck, it kicks on the fan high speed immediately on a cold start with cold air. If this were a true auto climate control system, the fan wouldn’t kick in until warm air was available and then the fan would gradually kick on.

After the latest Uconnect system update (from Nov or Dec I think?), my system stopped going full blast on auto in the cold until the truck has some temp going. It needs roughly 100° of coolant temp to start heating the cab.

When I remote start and get in the truck when the truck is still cold, the fans are on blast, but as soon as I kick over to ignition the auto control settles the fan down until coolant temp comes up.

 

[SpeedyV]

After the latest Uconnect system update (from Nov or Dec I think?), my system stopped going full blast on auto in the cold until the truck has some temp going. It needs roughly 100° of coolant temp to start heating the cab.

When I remote start and get in the truck when the truck is still cold, the fans are on blast, but as soon as I kick over to ignition the auto control settles the fan down until coolant temp comes up.

That’s great to hear, and I experienced the same while on the road this week.

 

[geotex1]

If you want a trick from the guy that lived on the cold coast a long time, put a satchel of dessicant in the truck. It'll absorb excess moisture that stays trapped in the modern tight cabins, and will help with fogging. DampRid is one convenient brand with various containers.

 

[2019REBEL]

If you want a trick from the guy that lived on the cold coast a long time, put a satchel of dessicant in the truck. It'll absorb excess moisture that stays trapped in the modern tight cabins, and will help with fogging. DampRid is one convenient brand with various containers.

That's what I do, every winter cause you are always going to track in snow and your breathing introduces more moisture also.

 

[dutchman187]

If you want a trick from the guy that lived on the cold coast a long time, put a satchel of dessicant in the truck. It'll absorb excess moisture that stays trapped in the modern tight cabins, and will help with fogging. DampRid is one convenient brand with various containers.

This is a helpful tip, thanks!

 

[BiLlYDeE]

After the latest Uconnect system update (from Nov or Dec I think?), my system stopped going full blast on auto in the cold until the truck has some temp going. It needs roughly 100° of coolant temp to start heating the cab.

When I remote start and get in the truck when the truck is still cold, the fans are on blast, but as soon as I kick over to ignition the auto control settles the fan down until coolant temp comes up.

I’ll check this next time .. thanks!