Heat blowing and thermostat control issue (1 Viewer)

[Michael T]

First lexus i have owned, but the heat and AC system is maddening. It is 25 degrees outside today. Car heats up fine and quickly, but once it gets to a good hot temp in the car the blower will keep blowing hot air no matter how low i turn the thermostat. I find myself constantly having to open my window to let the heat out, turn off the blower completely, or hit the a/c button and crank to “LO” just to get some cold air to to come out and try to control how hot it has gotten.

Is it like this with all Lexuses?

 

[RIDEaCANYON]

probably our only "complaint" with our also. wondering how much is operator error vs just poorly designed system in our case. Seems like the temp sensor in the cab is not accurate/functioning.

 

[Michael T]

probably our only "complaint" with our also. wondering how much is operator error vs just poorly designed system in our case. Seems like the temp sensor in the cab is not accurate/functioning.

Switching climate concierge on or off has no effect. Don’t see any other options that would control temperature automatically, so not sure how much operator error there is

 

[BETN]

My wife has been complaining about this since the first time she rode in the car. I'm hoping this is something they can fix with a software update. It's on the list for my 5k mile service in a week.

 

[adinkels]

I am experience the same issue. I usually just turn the temp to low before turning off and the air that comes through is tolerable. Will also try turning off the recirculation.

That all said, I am experiencing temperature control issues. The heat pumping out at 62 degrees is the same as 80 ... very hot (I haven't tested with an HVCA meter, but it is obvious.) Oddly, I was playing around with the drive modes and the temperature regulation started to perform 'normally'. Upon restart, the issue returned. Already mentioned to Lexus and will pursue again when I bring in for brake replacement (known issue when driving in reverse) and passenger seat massager (another acknowledged issue).

 

[radd31]

I took my GX in for this exact issue. Lexus was zero help at all and said it was normal. It’s very frustrating

 

[FJMainiac]

Another workaround. Make sure fan is off or lowest setting, then redirect air flow to the feet.

 

[Ellie B]

I am experience the same issue. I usually just turn the temp to low before turning off and the air that comes through is tolerable. Will also try turning off the recirculation.

That all said, I am experiencing temperature control issues. The heat pumping out at 62 degrees is the same as 80 ... very hot (I haven't tested with an HVCA meter, but it is obvious.) Oddly, I was playing around with the drive modes and the temperature regulation started to perform 'normally'. Upon restart, the issue returned. Already mentioned to Lexus and will pursue again when I bring in for brake replacement (known issue when driving in reverse) and passenger seat massager (another acknowledged issue).

Hello! Would you mind to expanding on the known issue regarding the brakes in reverse? My brakes squeal only when in reverse. I took it in to Lexus last week and they told me it was because the weather is cold. Hoping if my issue is similar to others I might be able to bring it up again to them. Thanks so much!

 

[Ellie B]

I also have the exact same issue with the interior temperature. Lexus told me they couldn’t replicate the issue.

 

[Michael T]

I also have the exact same issue with the interior temperature. Lexus told me they couldn’t replicate the issue.

This is such an easy issue to replicate, as it is not intermittent on mine and i suspect not on others. Very simple test… wait until car heats up and blowing hot air, then wait till cabin gets hot, then turn dial to anything in 60 temp range, and they will see the air blowing from vents remains like a furnace…

I would ask the service tech to ride in the car with you, if your 550 is like mine, it happens every time and undeniable.

Multiple different passengers riding along in front seat have noticed and commented on it, asking why my air doesn’t get colder when they turn down the thermostat knob when the cabin starts getting too hot

 

[Michael s]

First lexus i have owned, but the heat and AC system is maddening. It is 25 degrees outside today. Car heats up fine and quickly, but once it gets to a good hot temp in the car the blower will keep blowing hot air no matter how low i turn the thermostat. I find myself constantly having to open my window to let the heat out, turn off the blower completely, or hit the a/c button and crank to “LO” just to get some cold air to to come out and try to control how hot it has gotten.

Is it like this with all Lexuses?

I got the same issues and Lexus told me its normal the dealership told me its designed to feel the outside temperature

 

[radd31]

I took mine in for the same issue. They just said it’s normal. It’s definitely not normal.

 

[DiscoPotato]

Same issue here and it is maddening. I should not have to open my window to get the air a bit cooler. It doesn't matter if the temp is set to maximum hot or 60, it will be blowing the same temp air. I've tried turning auto off, recirc off, a/c off, left everything in auto, s-flow and eco are off. Doesn't matter what setting it's on. #1 complaint with this truck and despite what anybody says, this HVAC behavior is NOT normal.

Edit: I have an OT model.

 

[cmfhsu]

This is such an easy issue to replicate, as it is not intermittent on mine and i suspect not on others. Very simple test… wait until car heats up and blowing hot air, then wait till cabin gets hot, then turn dial to anything in 60 temp range, and they will see the air blowing from vents remains like a furnace…

I would ask the service tech to ride in the car with you, if your 550 is like mine, it happens every time and undeniable.

Multiple different passengers riding along in front seat have noticed and commented on it, asking why my air doesn’t get colder when they turn down the thermostat knob when the cabin starts getting too hot

Lol - one of my sales people actually complained about this during my test drive and asked me to turn down the temperature.

In my car, it seems to only be a problem between 30F and 60F, which is a shame because I'm within that range a lot during fall, winter, and spring.

Does everybody experiencing this have the Cold Weather Package or have OT trims (which come with the Cold Weather package standard)? I wonder whether Toyota simply tuned the "Fast Response" PTC heater with a dumb timer, overly heating the cabin until a ~20-30 minute timer expires. If owners who do not have the Cold Weather Package don't experience this, then we've got a lead on why this happens.

On the plus side, this is maybe the most effective PTC heater in a non-electric car I've ever experienced. I can't tell when they're running in other cars - including other Lexus models like my friend's ES.

 

[SkyHigh]

I have the cold weather package and mine does this too.

 

[BryanM68]

I have an OT and mine does this too.

 

[cmfhsu]

Anybody without the Cold Weather package feel like their climate control overheats the cabin?

I wonder if there's a dedicated fuse for the PTC heater. It's just a fancy Lexus branded space heater.

 

[lowrange44]

My 2025 does the same thing. Today, with the climate set at 62 and still blowing warm/hot air, I turned off “auto” mode by manually adjusting fan speed. The air coming out of the vents seemed to get cooler. Give it a try and see if it helps. I’ll have to mess with it on a longer drive to make sure it wasn’t just my imagination

 

[SkyHigh]

My 2025 does the same thing. Today, with the climate set at 62 and still blowing warm/hot air, I turned off “auto” mode by manually adjusting fan speed. The air coming out of the vents seemed to get cooler. Give it a try and see if it helps. I’ll have to mess with it on a longer drive to make sure it wasn’t just my imagination

I just tried this and here's what I did, for what it's worth...

Remote started GX with climate settings set to 74, drivers heated seats on and heated steering wheel.

Coming out of the neighborhood it was getting hot so I turned down the heat to 66.

As I was stopped at a light, I turned off auto and it still was blowing hot.

Started driving again and turned auto back on and it started blowing cold.

Maybe we can find a pattern? Remote start? Auto off then on?

I have all the other climate stuff turned off like eco, S-flow and the concierge.

 

[cmfhsu]

I have everything enabled except eco climate. Auto everything - auto climate, auto AC, auto recirc, Climate Concierge, S-Flow.

I don't remote start my vehicle or warm it up before driving. I wait 20 seconds for the cold start cycle to complete, then drive away immediately. Frankly it's only a problem when it's between 35F and 65F ish. When it's around freezing or colder, the car gives perfectly reasonable heat.