2023 HVAC issues - hot floor vents, front vents off by 10 degrees

[Chronicle]

I've had this problem since new and the dealer says "normal" and that all GX's do it. Lexus said pound sand.

Example, AC on , dual zone off, temp 70, driver face vents are 10 F colder than passenger and the floor vents are 100 F. I've measured all of this and the dealer confirmed it (but it's "normal" they say). Setting temp to 65 F same thing. Setting temp to LO and all of a sudden both sides and floor drop to 50's F. Change back to 65 F and everything reverts.

Has anyone else experienced this?

 

[Banandalorian]

It's not normal for the vents to blow hot air when the AC is on. I don't know what the problem could be - maybe something with the blend doors within the system not working right.

It sounds like your dealer is trying to get out of warranty work to take the dashboard apart.

 

[r2m]

Is there a reason you're not using the individual climate controls and just have them both set to 65°F (or whatever) on both sides?
We have the 3 climate zones and keep them at 73°F year round and works great!
We did have an issue once thinking the AC was broken when traveling through Texas in July and we kept having hot air blowing on us.
After pulling over and investigating, found out the rear (second row) seat climate control was set to 80°F!
After setting to a "normal" temp, all was good and cool.

 

[Hiluxforever]

To be fair, temp sensors can drift a lot without annual calibration. I am currently a Mechanical Engineer and was an Instrumentation Engineer.

Either your blend door is malfunctioning or your sensor has seriously drifted

 

[Chronicle]

Is there a reason you're not using the individual climate controls and just have them both set to 65°F (or whatever) on both sides?
We have the 3 climate zones and keep them at 73°F year round and works great!
We did have an issue once thinking the AC was broken when traveling through Texas in July and we kept having hot air blowing on us.
After pulling over and investigating, found out the rear (second row) seat climate control was set to 80°F!
After setting to a "normal" temp, all was good and cool.

Plenty of times it's just me in the car. If I want actually 70 I can't really get it because the passenger side is 10 F higher. I would at the very least have to set both sides. Can it be done? To degree yes but it should not have to be.

Do your floor vents come out hot with the AC on?

 

[Chronicle]

To be fair, temp sensors can drift a lot without annual calibration. I am currently a Mechanical Engineer and was an Instrumentation Engineer.

Either your blend door is malfunctioning or your sensor has seriously drifted

It's been this way since I bought it. I could connect OBDLink to see the cabin sensor temp if that would help.

Would replacing the blend door rule it out as the problem or could this be hard coded into the HVAC? I say this because the dealer says they all do it.

 

[Hiluxforever]

It's been this way since I bought it. I could connect OBDLink to see the cabin sensor temp if that would help.

Would replacing the blend door rule it out as the problem or could this be hard coded into the HVAC? I say this because the dealer says they all do it.

I would see what temp it's seeing, just as a gut check. It could help eliminate it as an issue which might limit it to something related to function or control of the blend door

 

[r2m]

Do your floor vents come out hot with the AC on?

Nope, never felt hot air coming from under the dash or floor with AC. In fact, to get the seat coolers to BE cooler I will set the AC to the floor so the cold air blowing on the floorboard will continue blowing under the seats and will then be picked up by the seat cooling fans and provide a cooler seat.

 

[Chronicle]

Nope, never felt hot air coming from under the dash or floor with AC. In fact, to get the seat coolers to BE cooler I will set the AC to the floor so the cold air blowing on the floorboard will continue blowing under the seats and will then be picked up by the seat cooling fans and provide a cooler seat.

Well it definitely sounds like this is a problem then. What year is yours?

The problem is I can't get Lexus to touch it. I've been on the phone with them numerous times talking to their "handlers" who are there to simply wear you down.

 

[r2m]

Well it definitely sounds like this is a problem then. What year is yours?

The problem is I can't get Lexus to touch it. I've been on the phone with them numerous times talking to their "handlers" who are there to simply wear you down.

2013 premium.

 

[Hiluxforever]

Mine is 2015 base with 3 zone Hvac and i have no issues. Works better than the stuff I have at work which is way more sophisticated.