I am hunting a ground loop issue with my audio system and i want to find out if the alternator is the culprit. Is it possible to take the alternator out of the electrical loop for a short time for me to do a test. I don't see a relay or anything i can just pull to test this out.

 

No relay you need to pull the three pin plug on the back which feeds the warning light and that will stop it charging,

 

Alternatively, you can pull Fuse #2 (5A) in the Engine Compartment Fusebox. Removes B+ feed to the alternator regulator.

 

As always Michealh right again though there is always the chance the alternator will self excite is revved hard

 

^^
I found that out too late when my alternator decided to go south just before storm Ciaran.

Point taken though over possible self-excitement - residual magnetism?