Same issue as stated in NHTSA id numbers 10881898, 10761786 and 10748834. Sporadic seat cooling problem -- panels on seat back sometimes heat in cooling mode. For one test I did, the car was in the garage and cool (so existing heat from the car being parked in the sun was not a factor). I started the car, turned on the seat coolers and got out (so body heat was not a factor). I could very specifically feel heat on the top panel of the seat back (both the driver's seat and the passenger seat). I took it into my local Lexus dealer (September, 2015) and they reported "seats cooling properly without fault". however, as there are 3 other complaints on this issue, there would perhaps seem to be a non-isolated problem.

- Powell, OH, USA

When ventilated seat is turned on the back heat up and gets really hot! it's almost like burning hot. Only the bottom feels cool.

- Rosemead, CA, USA

When I am using my ventilated seats the bottom of the seat is cool and feels good but the back upper portion near shoulder blades feels like its being heated. I have the cold air on in the car and the cold air on in the seats and I can have both at maximum cool and it will still heat up. Worse is that it is random but has been occurring on other cars too as seen in forums. When you turn the cooling seats off it will cool down and when you turn them back on then it will heat up again.

- Miami, FL, USA

When I'm using my ventilated seats the bottom of the seat is nice and cool but it feels like the my back is being heated. I always have ventilation on lowest setting. The top of the seat between shoulder blades... very hot!"?" seriously. I felt it with my hand, as if the ventilation was shorting the heating elements. It stayed hot a while after I turned off ventilation. Then it cooled. Had this happen to me on my way home. The bottom of the seat was cooling but mid back the seat got very hot. Turning it off did cut the heat and then it would come right back when I turned it on. And it seemed to be gone. This happened to me. To make sure I turned on the ventilation on the passenger side too, no one sitting in it. It warms up at the same spot as the driver side. Just below shoulder blade area. The seat portion is cool and you can feel the air. The back (warmer part) is not emitting air, but just hot. Turned the switch on and off, but still gets hot in the the back. Finally, turned the car off for about 10 minutes. Turned it back on, and the problem went away. However, I feel that this problem will return. Just used vented seats I experienced the exact same thing. Cooling on the seat and it got very hot about where my shoulder blades are. It was uncomfortable enough that I was cooler leaving them off. I take it into the dealer for the 5K checkup soon. The back of the seat heating is really annoying!! hope it's a quick fix! they can't replicate the problem, thus unable to diagnose. Although I'm not happy with the fact this problem is not resolved, I know that the problem is occurs at random. We just have to keep them aware that the problem exist by reporting it. The service writer created a case number (it's printed in the paperwork) and submitted to Lexus Corp. Hopefully we get a fix for this soon.

- Sanford, FL, USA