Constant Battery Drain. Daily Driver Help!
1999 F250, 7.3, 4x4 Auto
If I let my truck sit for more than a few hours, it has kills both batteries. I disconnected both negative battery cables and put a volt meter between the driver's battery negative terminal and cable. The truck has a steady 11v-12v draw with ignition off, key out and doors shut. I pulled every single fuse under the hood and under the dash 1 at a time and didn't see any noticable difference (at most half a volt for keep alive memory and the like).
What would cause a steady 12v draw that isn't on a fused circuit? I already disconnected the alternator thinking maybe a diode went bad in it, but no luck.
Another strange symptom, might be related, might not. I can operate my power windows and radio even with the key out of the ignition. Occasionally the radio will literally turn itself on. The marker lights have turned themselves on a few times, too.
Please help. This is my daily driver and plow truck.