hello all i have a 97 blazer just changed head gaskets, and whole top end gaskets, went to start the truck after i was done and the truck has no power at all, no interior light, no dash lights, no head lights no horn, it wont crank over or get a click out of the starter, no power at all its just like it has no battery in it, it has a good battery and i had my jump box on it to, the only fuse box i have is on the drivers side of the dash, i checked them all they are good, i dont have a fuse box under the hood, i have been a mechanic for 15years and i have never delt with this before... does anyone have an idea?

 

Do you have 12v measured to chassis, at the alt output? Check that plastic box to the right of the AC compressor {or where it would be}