tl;dr - make your door switches last forever, make your windows move faster without replacing the tracks, and do it without a rats nest of wiring
Inspired by
this thread and the wiring mess I found in my truck today, I decided to design a small (37mm x 33mm, and 20mm high) PCB. Here are some eCAD screenshots - going to get some boards fabbed and tested in my FJ62. This mod will reduce the current passing through your switch contacts from ~7A to ~40mA (0.04A), which means contacts won't arc / pit.
Boards include:
- flyback diodes to protect against back emf from the coil discharge on switching.
- a side mounted molex connector on there so that you don't have to solder anything - just need to pin in a connector.
- automotive grade relays - the relays I chose are capable of sustaining 20A each, so they should last a long time.
- 3x 140mm mounting points so you can zip tie or mount to something. In the shipping version I'll probably reduce the hole size and 3D print a little enclosure box...for prototyping I want zip tie access

Going to modify the design tomorrow to support a different relay that has both a 12V & 24V coil version, so that I can solder in whatever people need and send them out. If everything tests well I'll implement these in my truck and sell them if anyone is interested.
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