While the A/C is on, The Jeep randomly blows HOT air from the floor vents for 3-5 mins then stops

[ferrellmc]

I have had mine unplugged pretty much all summer with no problems. As far as what the shop foreman said, that's fine as long as it goes through the hvac system and not just dump it from the outside straight into the cabin. That's how it should have been designed,imo.

I agree. They should have designed the vent to open toward the plastic cage, that way when the vent opens, outside air has no place to go but through the filter and HVAC. Another way would be to open the vent a very small amount so it would become mixed and part of the cabin air and sucked into the filter/HVAC. As it is now, it's as if the windows roll down for about 10 seconds.

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[cobra]

I was concerned that the defrost would not work well when it gets cold because it uses outside air. It's been wet and cold here and the defrost has been working fine. It will probley just stay unplugged.

 

[jeremyjeep]

You can find another dealer near you by entering your zip code here: https://www.jeep.com/find-dealer.html. The dealers listed with the blue and white "Customer First" logo have achieved the highest level of customer experience recognition.

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None of the dealerships within at least 3 hours of me have the “Customer First” logo. I can personally testify that 2 in my area have a Customer Last attitude. And lots of negative Google reviews confirm my same experience.

 

[Cypher]

We just noticed ours doing this on our trip from AZ to mo. My wife kept saying she was getting freezing cold air blowing on her while the heat was on from behind the glove box. This not only lets in hot air in the summer, and cold air in the winter, it also lets in nasty smelling air when driving past large CAFO (cow farms) and lots of dust when off-road. This could actually be a health risk since it is not going through a cabin filter of any kind. In AZ there is a thing called valley fever. You get it from bacteria in the dust. So if you happen to be out and a dust storm hits, this could kick on and suck in dust, causing you to get sick. I could see this actually being pushed in areas where there is a lot of dust and someone having issues. I understand the need for outside air, but should run through a filter, or have a way to disable when recirc is on etc.

Horrible design. @JeepCares , please add this as one more thing we ar dealing with in our 2019.

 

[GRAK]

Seconded on this weird venting issue. I got my Jeep in August so found out right away that every once in a while it'd let in outside (115º) air for a moment. Have been in a few dust storms & also wondered about the valley fever thing. No good!

 

[RubenZ]

Was this fixed in 2019’s?

 

[Cypher]

Was this fixed in 2019’s?

Nope, mine is a 2019.

 

[californiajeeping]

Was this fixed in 2019’s?

No but they fixed the way the dome light operates in the 2019. Priorities. lol

 

[californiajeeping]

Seconded on this weird venting issue. I got my Jeep in August so found out right away that every once in a while it'd let in outside (115º) air for a moment. Have been in a few dust storms & also wondered about the valley fever thing. No good!

Brilliant. FCA designs the vents to open randomly, dust gets in, FCA refuses warranty due to dust in the cabin. https://www.jlwranglerforums.com/forum/threads/dust-in-cab-voiding-warranty-repair.24905/

 

[mgroeger]

We just noticed ours doing this on our trip from AZ to mo. My wife kept saying she was getting freezing cold air blowing on her while the heat was on from behind the glove box. This not only lets in hot air in the summer, and cold air in the winter, it also lets in nasty smelling air when driving past large KAFO (cow farms) and lots of dust when off-road. This could actually be a health risk since it is not going through a cabin filter of any kind. In AZ there is a thing called valley fever. You get it from bacteria in the dust. So if you happen to be out and a dust storm hits, this could kick on and suck in dust, causing you to get sick. I could see this actually being pushed in areas where there is a lot of dust and someone having issues. I understand the need for outside air, but should run through a filter, or have a way to disable when recirc is on etc.

Horrible design. @JeepCares , please add this as one more thing we ar dealing with in our 2019.

Thanks for the reminder!!! We've had ours for over a year now and this "feature" sucks. FCA actually called the dealer while I was sitting there and told them it was designed this way so that fresh air could be brought into the cabin so there would not be low Oxygen levels. The service manager told me this and we both laughed and rolled our eyes.
The reason I say thanks is we are headed to AZ, UT, CO in July to off road and I never thought about the dust. There is another guy with a thread about so much dust getting in that is clogged up his A/C or something.
A service tech offered a quick remedy... make sure you are on recirc and that the vent is properly closed, then disconnect the wiring harness that goes to the vent damper. This will leave you in permanent recirc which will not allow the damper to dump "fresh" air in but it may cause some trouble with defrosting fog since you can't get that fresh in to eliminate the foggy windows.
I have an idea I want to try. There has got to be an individual wire that goes to the damper to control this unwanted opening and closing. It happens regardless of recirc being on or off so there's got to be something else sending the signal to do it.
I want to find that wire and cut it. I'll report back if I ever find time to do this

 

[Jeepsterfreak]

Thanks for the reminder!!! We've had ours for over a year now and this "feature" sucks. FCA actually called the dealer while I was sitting there and told them it was designed this way so that fresh air could be brought into the cabin so there would not be low Oxygen levels. The service manager told me this and we both laughed and rolled our eyes.
The reason I say thanks is we are headed to AZ, UT, CO in July to off road and I never thought about the dust. There is another guy with a thread about so much dust getting in that is clogged up his A/C or something.
A service tech offered a quick remedy... make sure you are on recirc and that the vent is properly closed, then disconnect the wiring harness that goes to the vent damper. This will leave you in permanent recirc which will not allow the damper to dump "fresh" air in but it may cause some trouble with defrosting fog since you can't get that fresh in to eliminate the foggy windows.
I have an idea I want to try. There has got to be an individual wire that goes to the damper to control this unwanted opening and closing. It happens regardless of recirc being on or off so there's got to be something else sending the signal to do it.
I want to find that wire and cut it. I'll report back if I ever find time to do this

You might be correct about a signal wire. How many wires are there on the harness? I can’t imagine that harness controlling anything more than the specific damper motor. I’m not an electrical engineer, so know nothing about electric DC motors other than they use a two wire lead to spin them. Stepper motors on the other hand might use a third lead that sends a signal for armature position. Remembering my R/C car and airplane days using servos with 3 lead connectors.

There may not be a single wire that controls the unwanted automatic opening of the damper door that can be snipped. It’s most likely controlled by the HVAC control module that sends the signal to operate the damper motor through the same wires that control the damper door manually when pressing the recirc button on the dash. Just throwing that out there so you can investigate further.

I suspect it’s a simple software code edit that needs to be made. Jeep can keep the system automatic but just recode the software to fully open/close the damper instead of partially opening the damper. This would be the fix.

Oh and from what I can remember reading older posts in this thread, is that the automatic partially opening/closing of the damper happens even with the recirc button off as well. This makes no sense since the cabin is being supplied with “fresh” outside air when the recirc button is off anyways. What really makes no sense is how Jeep engineers screwed this up so badly. They have no common sense.

 

[RubenZ]

Guess I’m still leaving wires unplugged. Haven’t had it happen since I did the fix posted early in this thread.

 

[Jeepsterfreak]

Guess I’m still leaving wires unplugged. Haven’t had it happen since I did the fix posted early in this thread.

If you need fresh air just crack a window or better yet drop the front windshield!

 

[Jeepsterfreak]

Is anyone reporting this to the NHTSA? Obviously not a safety concern except for the fact the system is allowing unfiltered outside air to enter the cabin during a dust storm or allows harmful exhaust gases to enter the cabin unintentionally in heavy traffic or tunnel where you might normally just hit the recirc button to close the damper. It’s not simply a hot/cold comfort convenience issue.

Maybe NHTSA reports would help trigger something with FCA to investigate further.

https://www-odi.nhtsa.dot.gov/VehicleComplaint/

 

[mgroeger]

UPDATE:

Went on a long trip and I popped the glove box to take a look. Like teh video in this thread shows, the damper goes into a half way position... half way between recirc and fresh. This allows the outside air to blow directly into the cabin right OVER the filter which also allows it to pick up dust off the top of the filter and blow it into the cabin as well as any dust in the outside air.
One "solution" I found was as soon as you sense this outside air dumping in immediately hit the recirc button and it will stop what it's doing and put it into the mode you want. For example we run with recirc on, when the dump occurs I hit the button twice (first one puts it to fresh, second one puts it back to recirc) this way the dump is minimal.

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