I recently purchased a complete wiring harness to use as an organ donor for a project on my ‘87 3.2. As I disassembled the harness into its 20ish sub-harnesses I found some significant issues hiding in the fuse blocks.
The photo with the yellow fuse shows a wire that likely was over inserted at the factory. Note the ferrule isn’t crimped and the screw head isn’t bunged up. Likely not a high current circuit as the connection isn’t burnt.
The photo with the red/green wire and two cooked terminals drills down to a fairly serious issue that isn’t readily apparent without removing the wires and getting curious. Note the shinier of the two screws has a damaged slot likely from repeatedly trying to tighten the connection to fix the buried problem. Both terminal/fuse holders have loose rivets that hold the assembly together. I found this by tightening the screws then gently backing them off. The terminal on both connections turned very freely a few degrees before the screw loosened. Over time the loose rivet connection heated and discolored the fuse holder. Loose rivets! Anyone seen this?
The photo with the corroded connections is typical of many we see while troubleshooting. The badly stripped red wire has begun melting due to the heat generated by the lack of strands.
When you encounter a badly heated fuse holder it likely has lost its spring tension due to heat annealing the temper out of the metal component. I’m going to guess either phosphorus or beryllium is alloyed here to promote electrical and mechanical design requirements.
