Prospective buyers beware

[Rubicon Bob]

Here is my take on all of this.

We all pretty much agree that AUTO mode works fairly well. It is MANUAL mode that is in question. In AUTO mode, the computer makes the adjustments to temp, fan and outlets based on the temp we select. MANUAL mode works the same way except the person driving takes over as the computer. We decide what outlets, temp and fan setting we want based on the temp we select. We ARE the computer the does the AUTO mode. Simple as that. My JT works thee same as my '17 Grand Cherokee. No problems found.

Sponsored

 

[futzin']

I think (maybe) it's a difference of expectation.

1. In MANUAL mode, one person expects a set temperature of 72* to yield 72* air out of the vents at all times (assuming a warm engine).

2. In MANUAL mode, another person expects a set temp of 72* to yield the truck bringing the interior temp to that set temp as soon as the manually set fan speed allows. In other words, in MANUAL mode, you will get variant temps from the vents not a set temperature.

Now, expectations may differ beyond these two thoughts. But, does the JT essentially behave as presented in the second?

 

[Rubicon Bob]

I think (maybe) it's a difference of expectation.

1. In MANUAL mode, one person expects a set temperature of 72* to yield 72* air out of the vents at all times (assuming a warm engine).

2. In MANUAL mode, another person expects a set temp of 72* to yield the truck bringing the interior temp to that set temp as soon as the manually set fan speed allows. In other words, in MANUAL mode, you will get variant temps from the vents not a set temperature.
Now, expectations may differ beyond these two thoughts. But, does the JT essentially behave as presented in the second?

I won't speak for everyone, but on mine, the temp that is set is for the cabin temp. The air exiting from the vents will heat the cabin to the temp you set. How quickly will depend on how you set the fan. Once the cabin temp reaches set temp, the air coming out of the vents will cool down. It will keep the cabin at the temp that you set.

Using your description, #2 would be correct.

 

[Seansmd]

If accurate (and I've NO reason to think it isn't), this is an excellent summary. It is NOT how I'd personally like to see the MANUAL HVAC system operate, but that's ok with me as long as AUTO works properly. There's some disagreement on that too, it seems. But it also seems as though some here have a system that won't moderate even after reaching set temp in MANUAL mode. Between different expectations, terminologies, probable system discrepancies and clashing personalities, this issue has been confusing the hell out of me. As a person in the market for a JT, I'm keeping an open mind about it and have been reading this one with interest.

For me, a MANUAL system operating in this manner is too close to what the AUTO is supposed to do, but that's me. Test drives only reveal so much. HVAC in different circumstances/settings, towing tests, long sit seat comfort, rain/water leaks and such simply can't all be addressed in a test drive. I'm glad I can learn about these things here.

It moderates when it reaches temperature as many have stated. If not the truck needs service, or the expectation that the vent starts blowing 70 degree air when the cabin is set to 70 but not up to temp might be broken.

The heating system in my house when set to 70, it blows hot air until the thermostat reaches 70 and then either shuts off or starts blowing recirculated air depending on the fan setting.

The air temp at the vents are hot or ambient.

This is how it is.

 

[futzin']

Thank you, Bob. I'm hoping boiling it down starts to clarify for some of us how the thing works.

Personally, I feel like that implementation of MANUAL mode is way too similar to the AUTO mode. I'm just trying to figure it out. But it could be that some others here feel like MANUAL should yield full control of temp, fan speed and air direction; sounds like the owner's manual implies that. It's ok with me if that is not the case, I just wanna know what I'm gonna be buying and using!

 

[Seansmd]

Thank you, Bob. I'm hoping boiling it down starts to clarify for some of us how the thing works.

Personally, I feel like that implementation of MANUAL mode is way too similar to the AUTO mode. I'm just trying to figure it out. But it could be that some others here feel like MANUAL should yield full control of temp, fan speed and air direction; sounds like the owner's manual implies that. It's ok with me if that is not the case, I just wanna know what I'm gonna be buying and using!

It is the case and the exact same as all other modern manual HVAC systems with a temperature setting, even a knob/slider sets the thermostat, there is nothing different with this vehicle. You control the fan, you control, the vents the air flows from. and you control the set point for the temperature. If the AC is OFF(you control this) and the temp is below the set point it flows hot air, if it is above the set point it stops flowing hot air.

This vehicle behaves the exact sames as every vehicle I have ever owned in manual mode.

 

[Rubicon Bob]

I have been following this whole topic. Most of the time when manual mode is described, someone always starts saying that is wrong because auto mode works this way or that way. Other descriptions start getting to complicated and hard to follow. Sometime the best way to describe something is to dumb it down (easier to understand).

 

[futzin']

the set point

This is the point of contention, I think. Some see it as a destination temp, some see it as a constant temp.

I'm trying to take the emotion out of this. So the system sees the set point (in MANUAL mode) as a destination temp. Got it.

BTW, it matters not a whit to me what a house system does, or what other vehicles do. I'm just trying to figure out what THIS vehicle does.

 

[futzin']

I have been following this whole topic. Most of the time when manual mode is described, someone always starts saying that is wrong because auto mode works this way or that way. Other descriptions start getting to complicated and hard to follow. Sometime the best way to describe something is to dumb it down (easier to understand).

this is what I'm trying to do, without emotion or judgement

 

[Seansmd]

This is the point of contention, I think. Some see it as a destination temp, some see it as a constant temp.

I'm trying to take the emotion out of this. So the system sees the set point (in MANUAL mode) as a destination temp. Got it.

BTW, it matters not a whit to me what a house system does, or what other vehicles do. I'm just trying to figure out what THIS vehicle does.

It is no different than the slider or knob on any vehicle in manual mode. the set point between blue and red is the destination temp to use your vacab. The point of the house and other vehicle references is that they behave the exact same.

 

[Seansmd]

this is what I'm trying to do, without emotion or judgement

I am fine with this discussion as well, either the OP's vehicle is broken, or he can't understand simple closed loop systems. Not sure which, but this title is wrong and inflammatory, which is fine, but he refuses to hear feedback.

 

[futzin']

It is no different than the slider or knob on any vehicle in manual mode. the set point between blue and red is the destination temp to use your vacab. The point of the house and other vehicle references is that they behave the exact same.

I disagree, but it matters not. The JT does what it does regardless of whether I agree with you or not!

Since I don't have a JT, thanks for helping me understand how it operates.

 

[danielspivey]

I think (maybe) it's a difference of expectation.

1. In MANUAL mode, one person expects a set temperature of 72* to yield 72* air out of the vents at all times (assuming a warm engine).

2. In MANUAL mode, another person expects a set temp of 72* to yield the truck bringing the interior temp to that set temp as soon as the manually set fan speed allows. In other words, in MANUAL mode, you will get variant temps from the vents not a set temperature.

Now, expectations may differ beyond these two thoughts. But, does the JT essentially behave as presented in the second?

Exactly with #1. This is what the owners manual suggests. This is How my service manager said it should work.

As for #2, it appears that’s how many of the Jeeps work, but, theres no solid evidence in writing, by email or from a dealer to suggest this is correct. This is my main point. My dealer says one thing (#1) and jeepcares says whatever the dealer says is right. All I am asking for is some references or documentation to bring to my dealer to say he’s wrong. I can’t bring this forum to him and say “hey all these random forum guys say you don’t know what your talking about”.

 

[Gatorized]

@danielspivey
Ask your sales person if they have the reference guide that explains to them how systems work so they can explain it to the customer.

 

[Aero_JT]

@danielspivey

I know you have been asking for references which I have provided some in my earlier post:

https://www.jeepgladiatorforum.com/forum/threads/prospective-buyers-beware.26056/page-12#post-421756

In addition, as per version 3 of the manual, in the section under "Automatic Climate Control" (ACC), it has given details of the "Automatic Temperature Control" (which I believe is part of the ACC system that is directly related to the temperature setting, regardless of other override functions, e.g. air distribution mode or fan speed). In this section, it has mentioend:

"Next, adjust the temperature that you would like the system to maintain by adjusting the driver and passenger temperature control buttons. Once the desired temperature is displayed, the system will achieve and automatically maintain that comfort level."

And

"It is not necessary to move the temperature settings for cold or hot vehicles. The system automatically adjusts the temperature, mode, and blower speed to provide comfort as quickly as possible."

I understand that it does not directly talk about vent air temperature (vs set temperature). However, based on the above, "the system will achieve and automatically maintain that comfort level" and "...not necessary to move the temperature settings for cold or hot vehicles. The system automatically adjusts the temperature..." do not make specific reference to vent air temp = set temp (contrary to what you've been told by service rep). IMOH, the quotes above seem to imply that the vent air temperature will be higher or lower when it is trying to achieve the set temp when the cabin temp is lower or higher than the desired temperature, "as quickly as possible".

The reason is, if your cabin temperature is at 62 degrees, and if you desire it to reach 72, by blowing 72 degrees vent air it's going to take a heck of a long time to reach that (vs blowing 80-90 degree air, then "blend it" to around 72 after it reaches the desired temperature)

I am with you that the wordings in the manual does not provide all the details of the logic being programmed for "manual mode" of the ACC. It is likely a compromise to keep it "simple enough" for most users, but would be lacking for more "advance users" who wants more details. As such, people who is looking for more information would likely have to deduce what the system does, and yes I agree asking on forums of others experiences is a great way.

Thanks.

Sponsored