Brand new 2019 C300 Sport A/C, Heater...Issue?
Thread Starter
Member
Joined: Aug 2018
Posts: 153
Likes: 19
From: Louisiana
2019 C300 Coupe AMG Sport Package
Brand new 2019 C300 Sport A/C, Heater...Issue?
So, it's been pretty cold here in Louisiana and I've noticed that when I have the air set to let's say 80 (bc that's what I had it set to this morning) my vents blow hot and cold air out, not only that, it will switch up which vent(s) are blowing hot and cold air. It does this with a/c set to off and also on.
I will feel warm air then all of a sudden I get hit with cold air or one or two vents will start blowing cold air and one or two warm air.
Is this normal for this model and year or is something wrong?
I will feel warm air then all of a sudden I get hit with cold air or one or two vents will start blowing cold air and one or two warm air.
Is this normal for this model and year or is something wrong?
Super Member
Joined: Feb 2006
Posts: 798
Likes: 89
From: Bromley, UK
2017 C43 AMG Saloon
If the car has warmed up, it should only blow hot air. If it hasn't warmed up and it is cold outside, it will start cold and then slowly heat up.
I would try warming the car up first to say 80F then put the air on. If after a minute it is blowing hot and cold air, a visit to the dealership is
in order.
HTH
I would try warming the car up first to say 80F then put the air on. If after a minute it is blowing hot and cold air, a visit to the dealership is
in order.
HTH
Thread Starter
Member
Joined: Aug 2018
Posts: 153
Likes: 19
From: Louisiana
2019 C300 Coupe AMG Sport Package
I took it to the dealer, the tech stated that he felt the air doing as I explained. He ran a diagnostics test and it came back normal. He stated that everything was nornal, it's just the car trying to balance the temperature, "The air system has a lot of flaps that open and close."
I just don't agree that this is normal, 80 should blow 80 consistently.
Also, he also stated, "Try changing the settings to just dash vents and not floor and dash or defrost and dash vents." I've tried all of that for one, two, I shouldn't have to do that not run my defrost to keep the heat consistent.
I just don't agree that this is normal, 80 should blow 80 consistently.
Also, he also stated, "Try changing the settings to just dash vents and not floor and dash or defrost and dash vents." I've tried all of that for one, two, I shouldn't have to do that not run my defrost to keep the heat consistent.
MBWorld Fanatic!
Joined: Apr 2007
Posts: 1,489
Likes: 439
From: San Diego, CA
2024 EQE 500
Super Member
Joined: Nov 2018
Posts: 510
Likes: 64
From: Dallas Texas USA
2023 AMG EQE 53
Do have the controls set to Auto? It should decide where, the temp how much sir is delivered. I think something is out of wack, maybe a sensor or blend door control. The temp you set is the temp that the system is trying to keep, not the temp of the air coming out the vents but it shouldn't vary line you're describing.
Senior Member
Joined: Oct 2013
Posts: 300
Likes: 13
From: GA, USA
Current: '19 E450 Cabriolet - Past: '19 C300 Coupe, '12 SLK350, '16 E350, '14 C250 (x2), '09 CLK350
Thread Starter
Member
Joined: Aug 2018
Posts: 153
Likes: 19
From: Louisiana
2019 C300 Coupe AMG Sport Package
Do have the controls set to Auto? It should decide where, the temp how much sir is delivered. I think something is out of wack, maybe a sensor or blend door control. The temp you set is the temp that the system is trying to keep, not the temp of the air coming out the vents but it shouldn't vary line you're describing.
Trending Topics
Thread Starter
Member
Joined: Aug 2018
Posts: 153
Likes: 19
From: Louisiana
2019 C300 Coupe AMG Sport Package
This is the truth. If I were you @Brittnie Jane I would take it to another dealer for a second opinion- if that's possible. I have a 2019 C coupe as well and have been nothing but impressed with the climate control, mine actually leans a little bit on the warm side for me. (But everyone's temp perception/feel is different, which makes it tough to judge.)
it definitely gets warm, but suddenly being hit with cold air kinda sucks lol
Last edited by Brittnie Jane; Feb 1, 2019 at 01:58 PM.
MB World Stories
The Best of Mercedes & AMG
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
5 Underrated Mercedes-Benz Models That Don't Get the Love They Deserve
Verdad Gallardo
Mercedes 300D Has Pushed Well Past 1 Million Miles and It Ain't Stopping
Verdad Gallardo
10 Most Reliable Mercedes-Benz Models You Can Buy Used
Verdad Gallardo
Thread Starter
Member
Joined: Aug 2018
Posts: 153
Likes: 19
From: Louisiana
2019 C300 Coupe AMG Sport Package
So, are you saying that what I'm experiencing is normal? I've never had a vehicle do this, my CLA would blow warm air if it was set to 80 or any other warm temp until I set it lower
Senior Member
Joined: Oct 2013
Posts: 300
Likes: 13
From: GA, USA
Current: '19 E450 Cabriolet - Past: '19 C300 Coupe, '12 SLK350, '16 E350, '14 C250 (x2), '09 CLK350
Bottom line is if you're cranking it to 80, and cold air starts coming out before the car is actually 80 degrees (or close) inside, there's probably something wrong. MBs are not immune to irregularities - the E class I just turned in for the C coupe used to randomly blow out heat for about 5 seconds in the middle of GA summers. There's some threads around Benz forums on that issue, although it was never a big deal.
In most MBs, I just turn it to auto until it gets to a reasonable temp, then turn auto off and fine tune. If you can't just do that and have it work - I'd take it to the dealer that would fix it.
Super Member
Joined: Nov 2018
Posts: 510
Likes: 64
From: Dallas Texas USA
2023 AMG EQE 53
Money is right. The only thing I would add is that in Auto Mode, the air will come out of the appropriate vents. For A/C this would normally be the dash vents. For Heat it would be the floor vents. There are times where it blends the 2. A little air always seems to come out of those small vents on top of the dash that blow air onto the front of the side windows. In heat there is also always a little air that comes out of the top defroster vents. But if you put it in defrost all the air comes out those vents. What you originally described is not the way it should work so you've got an issue. You could try the manual dial to direct air to the dash or both or floor vents and see if at least the air comes out from where it should. There is a small return vent on the dash, don't remember where on what car that sucks in the air from the car to measure the temperature in the car. The goal of the Auto system is to get the interior temperature to what you set it at so in A/C for example the air coming out might be 55 degrees trying to get the car to 72 degrees. A sensor could be bad, a blend door bad, a computer black box bad, lots of things, but it's not normal.
Thread Starter
Member
Joined: Aug 2018
Posts: 153
Likes: 19
From: Louisiana
2019 C300 Coupe AMG Sport Package
Thanks ya 'll. When it cools off again here I will play around with the settings some more and see what happens. I will take it for scheduled service if it happens again. Y'all it's February and it's 80 degrees and humid...Gross
Thread Starter
Member
Joined: Aug 2018
Posts: 153
Likes: 19
From: Louisiana
2019 C300 Coupe AMG Sport Package
Will be taking car in for service
Just a little update, I will be taking my car in for service this Wednesday. A few days ago I tried to use the heat and it was cold, no matter what I did it would only blow cold/cool air. It was not very cold out this particular day, however, I had been at work and was freezing from the a/c.
It really seems like the outside temperature is affecting the heat and cooling system. It's like, it's warm out you don't need heat today! Today it is chilly out and the heat is working fine as of this morning.
It really seems like the outside temperature is affecting the heat and cooling system. It's like, it's warm out you don't need heat today! Today it is chilly out and the heat is working fine as of this morning.
Thread Starter
Member
Joined: Aug 2018
Posts: 153
Likes: 19
From: Louisiana
2019 C300 Coupe AMG Sport Package
I brought the car in yesterday at 7:00am, they called me to come back at 1:00pm, they could not replicate the issue(s). I was yet again so aggravated that they could not find the issue. We got in it and I drove it around with my actual salesman and the a/c heat system immediately started malfunctioning, he was like, "Oh, okay, it's definitely not supposed to be doing this. Something is definitely wrong.
Thread Starter
Member
Joined: Aug 2018
Posts: 153
Likes: 19
From: Louisiana
2019 C300 Coupe AMG Sport Package
My salesman and I drove it and got it to replicate the issues, they are ordering a new control panel.
Also, now my passenger side window has decided to malfunction and stop working off and on. Ughh!
Also, now my passenger side window has decided to malfunction and stop working off and on. Ughh!
MBWorld Fanatic!
Joined: Jan 2009
Posts: 3,830
Likes: 595
From: NY & FL
MB’s of all kinds.
What about just turning the temp up to high? Does it blow warm? The system has a climate temp sensor on it that helps regulate the air temp otherwise it will just blow hot the entire time.
MBWorld Fanatic!
Joined: Jan 2009
Posts: 3,830
Likes: 595
From: NY & FL
MB’s of all kinds.
It should be under warranty so no worries. Drop the car off and they give you a loaner anyways.
Thread Starter
Member
Joined: Aug 2018
Posts: 153
Likes: 19
From: Louisiana
2019 C300 Coupe AMG Sport Package
We tried high and 66 on one side and the temps felt the same.
Yep, it will be going in. Just sucks, it's only a month old. Still has the plastic wrap on some parts.
Yep, it will be going in. Just sucks, it's only a month old. Still has the plastic wrap on some parts.
Member
Joined: Feb 2022
Posts: 88
Likes: 11
EQS 450+
While we haven't had to use heating in SoCal, I did previously have an issue with my air conditioning. It would be set to AC Auto and a temperature such as 72 but the fan would not blow even after several minutes even though it was clearly hotter than 72 in the car. I tried pushing the "bigger fan" button and making it blow but it would not work.
The workaround I found until it was fixed by the dealer with a software update was to click "Auto" to turn it off and then to click "Auto" again to turn it back on. The system worked after that. So it may be a software issue.
The workaround I found until it was fixed by the dealer with a software update was to click "Auto" to turn it off and then to click "Auto" again to turn it back on. The system worked after that. So it may be a software issue.
