Dubbayoo

Is the 2006 heat/cooling always on with the A/C? I don't see a separate on/off button. I used to think they were only on when the adjuster **** is extended, but the light above them is always lit. I don't really feel much ever, to be honest.

BigBoomer

They are on when the light is on.
You push it to get it to pop out, and then rotate right or left for cool or heat and how much.
The centre position is off.
Push back in to get it out of the way.

HauntedKen

I believe you will find that everything is localized within, and under, the seats. For the function to work at all you M-U-S-T have clean filters in the seats, and your foam must be in good shape so the heated or cooled air will pass through the small vent channels. As with all peltier cooling devices the effect is somewhat limited, it is not a full refrigerant based a/c system, but it does its job if properly maintained.

Just to be clear, there is no connection to the main car a/c or heat.

Peacebay

Thats not 100% true. If you have the AC off on the main controls (so that AC compressor is not running) and turn the cooled seats on, the compressor will cycle on. They are true cooled seats using the cars air conditioning, not just vented with a fan.

HauntedKen

Peacebay: "Thats not 100% true. If you have the AC off on the main controls (so that AC compressor is not running) and turn the cooled seats on, the compressor will cycle on. They are true cooled seats using the cars air conditioning, not just vented with a fan."

I guess you do learn something every day. It is interesting that the compressor cycles when the seat temp adjustment is placed in the cool range. I would imagine that the engineers felt that an overall reduction in the ambient cab temperature would help the Peltier coolers in each seat do their jobs. However the seats are NOT cooled directly using the car's a/c there is NO direct connection between the seats and the car's a/c or heater system. They are actively cooled using Peltier coolers in and under the seats.


Here is a clip showing a tear down of the Lexus seats with Peltier coolers in place under the fans and the mesh heating material.

The LS430 seats with their Peltier coolers were state of the art at the time, and represented the only Lexus with actively cooled seats. At the time Lexus promoted the Peltier technology quite vigorously, particularly the fact that the cooling units themselves contained no moving parts.

For more information about Peltier cooling (aka Thermoelectric cooling) click here for the full story.

Peacebay

Wait, now I’m really second guessing myself. I could swear I feel/hear the compressor turn on when I turn the dial to cool the seats but come to think of it I never visually verified.

If I was incorrect I apologize for acting like I knew what I was talking about in my last post. Lol!

HauntedKen

Like I said, we all learn something every day, and even this many years later these cars are really engineering marvels, so much is going on. To be honest I am far from young and there is just so much to remember . . . I still find myself having to look up the steps required to reset the oil change reminder!