There are a few fuses to check. I attached two pics below. The first shows the fuses. The second pic shows the wiring to the passenger seat.
Based on your description, I suspect either there is a faulty ground for the seat or the switch itself is bad and can not control the load placed on it.
I had to provide pics in two parts simply because they are from different pages. However, you can see where the wiring connects from one to the other.
First, check the fuses I highlighted in the first pic. In addition to simply checking the fuse, I need you to confirm there is power both to it and out from it. Here is a link that you may find helpful:
Next, confirm the ground is in good condition. If you look at pic 3, you will see the ground I am referring to. It is under the seat. (G651) Make sure the wire to the ground isn't damaged.
Next, pics 4 and 5 show fuse location. Pic is under the dash, passenger side and pic 5 is the fuse box under the driver's side. I highlighted the fuses to check.
Let me know what you find.
Images (Click to enlarge)
Thursday, November 26th, 2020 AT 3:30 PM