Electrical / Alternator / Fusible Link / Something Else Problem

[statikuz]

Alrighty so a few weeks ago my alternator went kaput - replaced with Maxima alternator - went fine. Ran fine for a few days, then the truck just shut off when driving. Busted out the DMM and found that the positive terminal on the alternator was grounded somewhere. After much ado ended up tearing out the white wires that run to the alternator from the battery. The big white wire that runs from one of the connectors on the battery is still grounded somewhere! I've torn it out of the wiring harness all the way back to the firewall, where it goes in and comes back out, then runs to this connector:

 

 

... that connects to the mess of stuff attached to the positive battery terminal.

 

In this photo you can see the two white wires in question, the upper one runs to the alternator, and the lower one goes to the battery terminal connector as above.

 

 

One of my questions is, what is the thick black insulated section of the upper white wire? Also - what is the orange loop connector on the right side of the photo? The Chilton book mentions this as a fusible link? The white wire, which is shown in wiring diagrams as going directly from the alternator to the battery, goes through the firewall? Anyone know why?

 

Main question being - any insight on what could be wrong here? Probably not including all the pertinent information in the first post so ask questions if need be. Thanks for your help and happy new year!

Edited January 1, 2010 by statikuz

[headpeace]

where did you get the new alty?

[statikuz]

Ended up doing what should have been done in the first place - pull fuses to try and isolate the problem. Ended up being the rear cargo lamp switch that had gone bad. Unwrapped a lot of wires to figure that one out.

[Precise1]

Glad you got it sorted out relatively quick. I hate electrical issues!!

 

B