Hey all! Posted this in the v forum but thought the liftbacks might have the same issue so I should also put it over here. I just purchased a 2014 v (Canadian "Luxury" package). I was thrilled to find a used v with heated seats at a dealership, as they were one of my desired features since I drive hours at a time for work and have back pain. However, the brief test drive did not reveal that they seem to be terrible. I can tell that they're capable, because they're nice and warm for the first two minutes, but then they seem to turn off. They'll get pleasant again for one minute every 10 or 15 minutes, but the interval isn't predictable and sometimes they don't seem to come back on at all. I'm guessing this is because the thing is trying to save power, but this is not an area in which I want it to do that! The manual very helpfully points out where the on/off buttons are and not much else. Is there anything I can do to hack this? Is there a sensor that I could cover up to convince the system that my butt needs more heat? (The manual did say not to put a blanket down as it might overheat -- so of course I tried this to try and get it to simply heat, but to no avail.) I have been spoiled by my 2006 Jetta's heated seats that will cook me until I'm nice and toasty and limber, and I foolishly thought that all heated seats were created somewhat equal. Disappointed to find that I've sacrificed comfort to have a hybrid. Thanks for any tips anyone can provide!
I recall reading some posts on the same issue. First, it should be noted that the cycle on and off feature of the heated seats is a necessary safety feature. That being said I remember one post saying that his Toyota dealership removed the leather covering and discovered that the heating wires were not properly spaced. Once they were arranged as they should have been the problem was resolved. Hope that helps. Posted via the PriusChat mobile app.
The behavior of the heated seats Toyota's lawyers probably insisted on to avoid lawsuits is obviously different from what you consider optimal comfort. Based on Toyota's warning about blankets potentially causing overheating, I think that there is not any temperature measurement going on at all. Instead, I think that it's much more likely that there's a simple timer built into the circuit that powers the heaters. I doubt that the on/off regulatory timer is built into the seat, also. It seems more likely that the circuit is in/near the heated seat power switch. If that's true, then there's a relatively simple test and fix for your problem - power the heated seats with an always-on (in ready state) power circuit. Turning the seats off when they get too hot would then be up to you. You'd have to splice the seat heaters power leads somewhere, but maybe someone here has some insight as to where that should be for maximum convenience.
Also, the heated seats I have sometimes get too hot for comfort, rather than never getting warm enough, like yours seem to do. It might be a good idea to make sure they're working properly before you start changing around the wiring.
