My 2004 Regal looks and runs like new with very low mileage. It has almost all options except a sunroof. Anyway, the heated seats just stopped working (perfect time, December 20th). Checked both fuses in the interior fuse block and the one large fuse in the relay box under the hood. The lights in the switches (in the console next to the traction control switch) turn on, but no heat to either seat.

I doubt that the heating elements in the seats BOTH went bad at the same time. I've read about a "heated seat relay" somewhere in the circuit but just can't find it. I suspect this is the issue. Its part number is 25638146 and I've attached a picture of it. Likely it's used in Lesabres and other Buicks of that era also.

It's not plugged into the block under the hood. Does anyone have any idea where it is? It's about an inch square.

Thanks in advance, Mark

 

Look under the rear seat.

 

here are a couple diagrams for you for some fuse locations OP https://www.autogenius.info/buick-re...e-box-diagram/ - sorry ahead of time if i might have found the wrong one or it isnt related.