So about 90% of the time when I go to use my heated seat (driver's only), the back warms up as normal, but the seat blows cold air. This is not a condition where the seat heat is simply not working and it stays cold while the back heats up. No... There is literally cold air BLOWING through the seat as if I had the thing set to cooling.

I originally posted about this a couple years ago, but got no solution, and the problem has returned. Not at all pleasant in these Michigan winter temps.

Has anyone else experienced this? If so, what have you done to fix it?

 

The driver-side seat cushion and seat back heaters share the same fuse called "D S/HTR" and the same relay called "D−IG1". If the seat back heater is operational, then the problem is not related to the fuse or relay. You may not be getting power to the seat cushion heater either because it is disconnected, or a wire is cut, or you may have a bad heater.

 

With perforated seats, the blower under the seat that blows cold air when the seat temp **** is set to cool should only blow air when set to cool. (It doesn't blow heat when set to warm.) The heated and cooled front seats of the 430 work on the Peltier effect. (Google for explanation.) Given how the seat provides heat or cool using the same element embedded in the seat bottom cushion, it sounds like the heat/cool element or electronics in the seat is faulty.

 

Thanks fellas.

 

All I know is this; the damned heated seats in the Lexus suck. They just do. Mine is a UL; and it definitely blows hot air to warm the seats; but it takes forever (10 minutes plus) to get hot, and by then the car is toasty. This is by far and away one of the biggest failures about these cars, IMO.

I've swapped the control units under the seat to see if I could improve it; no change.

Oh well... Guess I'm nit-picking.

 

 

I agree with ncsucarjoc. The heated seats in my 05 LS 430 pale in comparison to the ones in the 2010 ES 350 I had but overall the LS 430 is a far superior car even though it is 5 years older.

 

I am having partly the same issue but mine are both blowing cold air even when I have the switch on heat or when I have the switched turned off. When the car is running, the seats are blowing so I hope someone answers your question