97 Av heated seats not working - need advice!

[V-Roc-Z]

it's been a long hard winter on the West coast this year, and i'm eager to fix the heated seats that have never worked in my 97 Av. anyone dealt with this ??
i'm hoping it's something simple... like in my Supra when the power windows had dirty contacts in the switch. tried that for the seat heater switch in the door and it didn't help. don't know where to look other than checked the 20 Amp fuse under the dash and it's good w/ power going to it.
i reckon there's a control unit for it somewhere as well as a relay ??

[ToyotaDealer]

most probably the seat heater switch, toyota #84751-20150. $66.59

but have the problem diagnosed by a dealership first, as it could also be the seat heater unit itsself.