For me my drivers side heated seat stopped working same as you. I read many people had the same issue as me, the plug for the drivers side seat is located under the passenger seat, and one pin inside the plug burns out. If you unclip the plug and use a flashlight to look at the pins of the plug you'll see the burnt one. If yours is the same with 1 burt out pin in it, here is the part on amazon.
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that one has no wires though so I ordered this one but its $40 more, it comes with all the wires already attached, you then clip the ones you don't need, and you just wire the 4 or 5 or 6 wires that are on the plug. Heres the link to that one to do it that way, in my opinion that was the easier option since i didn't have a solder gun.
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Hope this helps someone also. I would turn on the heated seats and they would automatically turn off after 60 seconds, but no heat at all. I redid y seats and the coil looked just fine, but I have read that some people also had a broken coil as the issue, it's a cheap flat matt with flat coils inside it. So I would do it in that order:
#1 check fuse
#2 check plug under pass seat for burnt pin
#3 take off seat cover leather and check heating coil.
#4 no idea, have never had 1-3 not work.