Hello,
I have a 2020 Toyota Highlander. The car has front and rear heated seats, front ventilated seats as well. Heated seats on the front, primarily the diver seats ar a hit and miss. They both work, but they are not getting hot. The passenger seat gets a bit hotter, while the driver seat is pretty much warm at it's best. However, at random times, the driver seat, as well as the passenger seat, gets a lot hotter, how it supposed to be. I am saying how it supposed to be because the seat has 3 positions for heat, low, medium, and high. The way it feels when you turn them on, I would say the high setting is not working or at least working whenever it feels like it. Most of the time the seats are lukewarm to warm which will explain the low and medium settings. At random times, sometimes after 20 minutes of cycling or after ON and OFF maybe, the seat gets hot, just like the high setting should be. I am not sure what is triggering this or what is triggering not to work at all times. The pads inside the seat are definitely good and they do get hot enough that you can actually use the dash switch for all 3 levels of heat. I asked Toyota and they gave me the usual nonsense, script copy and paste answers and they sent me to the dealer. I went to the dealer and after they did acknowledge there is a problem, they said they talked to Toyota and they have done a hard reset. Hard reset meaning disconnects the battery. They wasted 6 hours of my time, to tell me ''after the hard reset, seats are working as designed''. If by as designed they mean not working they sure nailed it. After the ''reset'' they did work normally, but this morning when I started the car they went back to previous symptoms. I am suspecting is something going on with the heated seat control module that is under the seat, given this behavior. Should I replace the module? The car is under warranty and Toyota pretty much refuses to replace anything. Is a 70$ part and maybe one hour to replace it. I am not sure a new one will fix the issue. What else can I do to test? try? Thank you
The computer that controls the heating is malfunctioning. Ask them to check the BCM and if they refused it, go to an independent mechanic and have it checked.
They don't want to check anything. I've been there yesterday and they said what I wrote above. However, they did nothing to really test it. The seat was not moved one inch and they even said all they did was to hard reset. I will need to find an honest mechanic in my area and see if they have the tools to check what you said. I wish Scotty was still in Houston, I could have seen him easily.
Get one of those infrared thermometers and measure the seat. Then go to a new truck on the showroom floor, put it on the same seat setting, and measure it too. That should be proof enough it's not working.
Yeah, I was thinking about it. Even though are expensive I can return them when I am done. Back seats are working great and I have friends with the same car but a lower trim and they have no issues, their seat works great. Thanks for the suggestion
Ahhh, I have one of these. I get about 98 on the back seats and 85-90 front seats. I was thinking of a thermal image scanner. I will argue with Toyota, not sure if they will accept this test. they already told me if the technician doesn't say is true then is not. I am looking for an independent mechanic now in my area that can scan.
I went to a mechanic since the Toyota technicians are even incompetent or they just don't want to do anything warranty related, or both. We found out what the problem is. Also is showing that all seats except the driver seat heat up to 125 degrees F. Drive seat starts at 90 degrees and drops well below 80 degrees in a matter of seconds and drops even more. I have a case open with Toyota and I am waiting to see when to go for service.
| DTC Code | DTC Detection Condition | Trouble Area |
|---|---|---|
| B14C1 | Seat heater temperature sensor malfunction | Air conditioning amplifier assembly Front seat cushion heater assembly LH Wire harness or connector |
nice work. Sometimes you just have to be persistent.