2017 Lexus Rx

My vehicle has 39800 miles (64k kms). I have the exact same issue with my driver side heated seat. The lowest setting may take time to warm up then gets scorching hot. Eventually after heating it up, I will turn it off manually to stop heating it, as it burns. My wife also mentions that the passenger side as well doesn’t seem to heat much. At this low of kms, I should not have this issue but saw someone else have the exact same issue. I have not taken it to the dealer yet as I fear they will charge a fee just to verify the problem. I have an old ES300 and I do not have this problem with the heard seat. My trim level is also the ultra luxury.

NHTSA Safety Complaint – Seat Heater Defect Vehicle: 2017 Lexus RX 350 Mileage at purchase: 45,430 Purchase date: Feb. 17, 2025 Dealer: Lexus of Tacoma at Fife, WA Description of Problem: The driver’s seat heater does not function properly. It is slow to activate (5–6 minutes), then overheats uncontrollably even when set to “LOW.” On multiple occasions, the seat became hot enough to cause burns through clothing. Defect Confirmed by Dealership Service Staff: Dealership staff confirmed that the driver and passenger seats heat at different rates. This matches a known defect identified in Lexus Technical Service Information Bulletin L-SB-0038-18 (Oct 10, 2018). Additionally, they confirmed that the drivers' seat spikes to uncontrolled high temperatures, even on the "LOW" setting. Despite this, the dealership refused to repair the issue without an extended warranty and suggested using a sheepskin seat cover to prevent further burns, which is prohibited in the vehicle manual. Safety Hazard: •The defect caused burns to the driver. •The driver's elderly mother, who has peripheral neuropathy in her legs, did not feel when the passenger heater was accidentally turned on, highlighting the risk of undetected burns should the heater defect remain unrepaired. •Risk of fire is also present given the uncontrolled heat and inherent electrical issue. Attempts to Resolve: Reported to dealership on 3/28/25. Dealer disclaimed responsibility. Reported again to dealership on 6/25/25. No response. Reported to Lexus Corporate Customer Service on 8/28/25. Summary: The seat heater malfunction is a confirmed manufacturing defect, already documented by Lexus in a TSIB. Not mentioned in the TSIB is the additional problem of uncontrolled heat spikes, which poses significant risk of burns or fire. Request NHTSA investigation and corrective action.