New to me vehicle. 2013 RX450h. So far so good but not sure the AC drivers seat is functioning. Is it noticable when it's on? Where should I feel it blowing? I can't tell if the system is just weak or not functioning. Otherwise, AC is running cold and strong. Would a repair of this be expensive/involved?

 

I can only share my experience and there is no blowing of air that I feel through the seat, but it does cool/heat the seat and the difference is noticeable after being out in the sun. or cold.

Salim

 

Are you sure you turned on seat cooling? (Doesn’t come on automatically with AC). Fan sound in seat is very low, almost imperceptible). Bet it’s working…

 

The seat is not air conditioned. It’s just ventilated with small fans. And yes it’s somewhat weak. But it’s better than nothing at all.

You might notice it better on a long drive when the interior has had a chance to cool down and There’s cool air under the seat. Also I find it feels amazing on a warm winter or fall day. But when it’s a 100 degrees out it’s just circulating hot air in the seat.

 

Here in TX, ventilated seats don't really cut it. I get a sweaty back and butt in the warmer months, which here in TX is May through October. I bought my 2013 Lexus RX350 in 2019 and it has ventilated seats, which, at the time, were a novelty for me.
Around a year later, in 2020, I rented a 2019 or 2020 Ford Expedition Max. The cooling effect of the front seats was vastly better. They worked so well that on longer drives I had to turn DOWN the cooling setting. I was disappointing that my RX ventilated seats paled in comparison.

I have some ideas to add actual air conditioning to my RX. I'm a mechanical engineer and I do a lot of product design and development so this is well within my skill set. I'm also a car enthusiast and have owned and upgraded multiple Toyotas in the past with extensive modifications - engine swaps, transmission rebuilds with updates, clutches, intercoolers, interior and exterior body mods as well. I installed the Grom Vline2 in my RX myself.
If anyone is interested in my project, let me know. I will start a thread as I make progress.

 

There was an old thread where someone increased the seat air flow with an addition behind the seat on the floor. See this:
https://www.clublexus.com/forums/rx-...ont-seats.html

 

repost:
The Lexus Auto HVAC directs cooled air to the dash vents when it is hot outside and
directs warm air to the floor vents when it is cold outside. A very simple hack to help
the ventilated seats work better is to tap the HVAC "Mode" button (right next to the fan
buttons) just once when it is hot outside. This will switch the damper doors from Dash vent
only to Dash and Floor. Now 1/2 your cooled air will be directed to your feet and seat!

 

I saw that hack a few years ago, probably here on CL. It doesn't work very well, and does nothing for the seat back, as it's compartmentalized and separate from the seat bottom. I took apart my seats to investigate how the ventilation functions and what parts it uses.
I'm working on a much better solution.

 

Yes, I'm aware of this, but it doesn't work much better than not switching the AC to feet on the HVAC screen. Also, this was the first thing I tried when I first got my car.
The OEM HVAC duct under the driver's and front passenger seats are designed by Lexus/Toyota to direct air at the feet of the rear passengers. This mostly bypasses the underseat blower. A small amount of heated or cooled air (from the duct exit) might get into the underseat blower. The air deflector fix (posted previously) attempts to force some of the air upwards into the seat cushion blower inlet. It won't do much of anything for the seat back, as that fan (axial, computer type fan) is mounted high in the seatback, in the hollow area of the seat back, and has no direct path to the air coming from the duct.

I've begun experimenting on my RX seats, and investigating the Ford Expedition Max (2018-2024) seat cooling. I've dissembled the seat cooling in my 2013 RX350, and I've run a couple of hacked together tests. I also believe I have an answer as to why the Ford cooling works so much better, and just an FYI, it's not due to TED units (Thermo Electric Device aka Peltier Junction, as Ford stopped using those around 2017. The 2020 Expedition Max I rented did not have TED units.

I thinking of starting a new thread on the subject of improved seat cooling for the 3rd Gen RX.

 

LS's have actual refrigerated seats while all lesser models have the ventilated seats.

 

I saw that mentioned somewhere during my searching last week. Today I explored that. The 2007-2012 LS460 uses TED units, similar to what Ford used from 2003(ish) to 2017. These photos show the Lexus part. Single blower, with 2 outlets, each feeding a TED unit near the end of the ducts. I'm pretty sure one goes to the seat back and the other goes to the cushion.