[Mysterytrain]

I posted that doctored schematic a couple of years ago to explain how that add on circuit worked. I stumbled upon the 'convenience' harness on ebay but was never able to find a factory schematic that showed how it was installed. I pieced together how it worked from questioning other Pelicans about the 'key off, door open' scenario that allowed the power windows to operate. It looks like the factory only used this old technology briefly before moving to a solid state relay box.
In the drawing above the only way the convenience relay operates is when the door jam switch provides a ground. Two possible failure modes would be the contacts 30 and 87 are fused together. With either relay this would allow the windows to always operate. It is also possible for a bad door jam switch to provide a constant ground path. This would keep the convenience relay energized and allow the power windows to operate at all times..and drain the battery.