You might try measuring resistance to ground of the B+ wire w/ the wire separated from alternator and fuse box. A good wire should always show infinite resistance or open circuit. If you wiggle, push, &pullthe harness around a brief short circuit occurs, the B+ wire must be replaced. I would suggest buying a separate equivalent wire and wire tying to existing harness rather than tear up the harness to extract the defective B+ wire.

good luck

 

where can you buy that B+ wire at?

 

I'm not sure what gauge wire, but match the original wire. Check shop manual for correct wire gauge or dimension and go to any automotive electrical shop for quality wire.

Did you find a short in the B+ wire?

good luck

 

I have been working a lot recently and havent had time to get in and try it out plus I dont have any kind of electrical wire tester so thats been hindering me as well.

 

One further test would be to disconnect and securely insulate the B+ wire at the Alternator. I would also disconnect the alternator plug connector. You would be running on the battery so don't try to go too far. If this fixes the problem, you know the fault must be the alternator. If problem still occurs, it pins the fault on the B+ wire itself (short in harness somewhere). As long as you don't run lights or AC, the battery should run the car for a couple of hrs easy.

good luck

 

interesting approach....Ive tried that on older chevys to see if the alternator or battery were going out but with cars that are injected and have ECMs I didnt want to try it for fear of messing something up. I'll give that a shot. Do you know if I can get this wire at an auto parts store or is it a dealership item??

 

You should be able to purchase B+ equivalent wire at any auto parts store. B+ provides charging current to the battery and supports load when alternator is working. When you remove the B+ wire and disconnect alternator, the battery must supply all current. I don't think you can damage the ECU, but can't be certain.

good luck

 

alrighty I'll give that a shot then.

 

chk the white/red wire that goes to the alternator, make sure it does not have a bare spot somewhere.. also there could be a bare wire under the under-hood fuse box,, and lastly could be a bad alternator itself
i'd look at the wiring harness first

sounds like something is moving just enough to make it touch ground and blow the fuse , if it was a true short it would blow the fuse instantly

 

thanks desert.