Loss of power to allmost all electrical

[BigTex]

My Grandson is the PROUD owner of a 1989 Comanche Sport, other than normal problems it is a great little truck, he calls it Blue and swears he will keep it the rest of his life.  Now the Problem, turn the key and nothing, checked battery and it is ok, checked starter and it is ok. Replaced the starter switch and nothing changed.  Checked the fuses and they are all good. The headlights work fine, but no tail lights, the brake lights work fine. no dash lights, no wipers, no blower fan. I installed a on-off switch and a starter button, the truck cranks right up and runs fine, but the other items still don't work, oh and the turn signals also don't work.  I added an additional ground strap but no help.  I am open to any ideas.  thank you.

[Eagle]

The '89 is about the same as the '88. Here's a link to the factory 1988 electrical manual. You'll just have to start tracing power from the battery to the main load center and see what's broken. Jeep used several fusible links back then, so it could be one of those.

 

http://www.bteventures.com//mj1988electricalmanual.pdf