99 OBS suburban. I have not permanently hooked up the heated part yet. The wiring to the power features is a constant hot ,but the wiring for the heated part requires a switch hot so they will cut off when the truck isn't running. I can run them on a toggle but need to find a switch hot wire to make sure that they cut off. I'm pretty much stoked my old seats were clapped out and didn't have an arm rest. I've got a 07 duramax and a 04 z71tahoe both with heated leather seats and have gotten spoiled with them lol.