My mothers Tauregh has an electical system.

Check for moisture under the driver carpet. Pictures 3, 4, 5 & 6 in the below link shows a WET wiring harness / loom, under the driver
carpet. Once wires get wet, they can cause circuits to short and voltage / power to go where & when it should not (such as lights staying
on when they are not supposed to. Or in the case that these pictures are from, the driver seat electric motors did not function any more due
to the power supply wire for those circuits being corroded (red/white wire i

You need to tilt the driver seat back to gain access to the battery.

Thomas