Drivers seat module is located under the seat, and works in conjunction with the Drivers door module, which, rather unsurprisingly, is located in the drivers door. (Also connects with other modules via the SCP network for memory setting/recall etc, but I doubt your issues will be anything to do with that)
Power for the seat adjustment motors is supplied to the seat module via a 30 amp fuse, # 21 in the rear distribution fuse box in the boot, and a 12v logic supply via a 5 amp fuse, # 7 in the primary junction fuse box in the drivers foot well. Power for the switch pack is via the same #7 5 amp fuse, and the lumbar support pump is supplied by the same 30 amp fuse # 21, but via a separate supply wire. If the lumbar pump is working, fuse #21 must be ok, so look at fuse #7, and if ok, check for 12 volts at pin #7, Orange/Yellow wire on the seat switch pack and also pin #10, Orange/White wire on the drivers seat module. If you have power going into the switch pack and seat module, and the motors still don't do anything, there's not much else except the seat module. Everything goes from switch to module to motor for basic adjustments. Individual motors can be tested by disconnecting at their appropriate plugs and feeding them 12 volt + and -. Doesn't matter which way round, as reversing polarity just reverses motor rotation, just make sure you get the motor power wires, not the memory position sense wires.
Hope this helps, let us know if you need anything more.