Seat heater issues

[Hhunter23]

I have a 2004 GMC Sierra 1500. The seat heaters are not functioning. When the buttons are pressed the lights just blink with nothing happening. Both drivers side and passengers side does this. I've checked fuses and connections but nothing seems wrong. Are the heaters themselves bad? Or is it something else? I hate having something that doesn't work so its driving me nuts! Thanks for any help or suggestions.