I have a 2004 SF LX 3.5L. The switch for the heated seats does not light when depressed- either R or L. Unless the heated seat temperature is quite low, the seats do not appear to be heating. I also noticed that the fuse in the HS position was a 25A instead of the recommended 15A. I replaced the 25A with a 15A.
At this point I assume it could be either the switch or the heater element. I wanted to make sure that all connectors are in fact plugged into the unit. Does anyone happen to know where it is located?
It appears that under the passenger seat there are two reasonably thin units, one with black fins and behind it a thin unit quite close to the bottom of the seat. It appears that it has a cable that goes up the back of the seat. Any ideas as to the problem or info on the units under the passenger seat would be greatly appreciated. Thanks!

 

As a follow up to this I finally took it to the dealer. The light on each heated seat switch (L&R) is actually a tiny bulb and not an LED. Dealer indicated that they burn out in about a year or two, often earlier as the switches are prone to being turned by piling something on the console and depressing them. Cost for the 4 bulbs is $14 and labor is $12. It was interesting that the service desk did not know why each switch had two bulbs and the service tech had already gone to lunch so I did not find out.

Ok- should have been obvious to me- one bulb illuminates the heated seat icon on the switch when the headlights are turned on and the other indicates that the heating elements are on.