once the heated switch turned on send signal to body control module which send ground to close heated seat relay, sending power to heated seat element, here is wiring diagram, first check fuse, if have test light can go to bottom of seat from rear, green two wire connector, on wire harness side, you should have power on pink wire going to bottom and ground on black wire on other connector going to seat back. Both elements are in series. Both run off fuse 13, both relays are located under seats. can also check by feeling relay will feel click when turned on..
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