Working on a buddies 91 Ford Ranger and the dam thing will not start. It has the 3.0 v-6 auto trans 2 wheel drive. Here what it does, you turn the key and the starter relay clicks. Have confirmed with a test light power to relay and out of relay down to the starter. Bench tested the brand new starter and its okay. The relay is also brand new. Battery has also tested fine. Can someone help me out here im at a lost of where to go next. Oh and all fuses has been checked.

 

Update. I have now lost all power to everything. Possibly lost a ground? Anyone know where some major grounds are on this thing?

 

Have you removed the battery terminals and cleaned them?