https://youtu.be/4NssZoAJEyE
How to fix your heated seats maybe of some help in three parts
I have no excuse now 🙂
The OEM seat cushion seat heating elements do not get particularly toasty before the incorporated thermal switch cuts off so one modification you might consider when replacing/repairing a damaged element is incorporating a 12V DC normally closed thermostat that switches around the 40 - 50C mark depending how toasty you want the seat . Digi-key do a few Cantherm circular flattish thermostats in this range and, from memory, I believe the current draw of the seat heating elements is some 8A so a rating above this is required - minimum 10A, preferably 15A or above (but measure the resistance of the element to check). These just need to be soldered in parallel with the existing thermal switch - no need to remove/replace it. I have modified both of my seats this way when replacing the elements and they are much better.