Find something hot or suddenly smell smoke from burning electricals?
Disconnect the battery until you can do some checking. Disconnect the battery post easiest to get to.
So far the common electrical trouble seems to be with:
Power seats in general...possible corrosion in the wiring under the carpet under the drivers feet.
Power lumbar support wiring shorts due to insulation being worn off the positive(+) wires.
The positive wires in most of the circuits are HOT at all times and due to the circuit being completed on the negative side of the devices, any connection inside the circuit, like a worn negative wire insulation shorting to ground before the switch can:
Make the device function without your control input.
Cause other devices in the module that is in the circuit group like door locks and interior lights in the power seat circuit to work intermittently.
Create a short straight to ground by way of worn insulation of a positive wire on to a grounded metal object.
Circuit breakers are installed to open the circuit before severe damage occurs...hopefully, so a little 5/16 combination wrench or even a little ratcheting 5/16 wrench available at most auto parts stores, will help you disconnect the battery quickly.
Personally, I've chose to set the lumbar support on my seats to the comfort of the primary driver then disconnect the wiring connector with the purple/blue wires going the the lumbar support motors under the rear of each seat.
All other ideas are most welcome and appreciated!!