On my 98 Suburban LS, I keep blowing fuse #13, a 20 amp one. This is the one that supplies power to the lumbar seat, the rear door speakers (right and left rear doors - not the back speakers in near the 'barn doors'), cigarette lighter, and the power door locks. Interestingly, I can still operate the power door locks with my key FOB. What happens is that periodically, after maybe a week or so, sometimes longer, sometimes shorter, the fuse just blows. I know that when fuses blow, this means that a power wire gets shorted to ground. So seeing that i rarely use lumbar, I would almost rule that out. Also, the fuse doesn't seem to blow when I operate the power door lock switch on the door itself. Could one of the rear door speaker leads be shorting against metal in the door or possibly in the wire harness between door and frame and after repeated opening and shutting, jars the power wire against a ground? I'm thinking that might be it, only since I sporadically use the rear doors?