Terry. Being totally Flipping useless with scopes, I wouldn't think twice about ordering and fitting a new alternator, We have fitted and sold dozens ( might even be hundreds ) of these Smart charge alternators and have never yet seen one that a new Alternator hasn't cured apart from the obvious broken B+ sensing wire and the odd one that someone has opened the pins up in the plug by sticking a test light or probe into.

If the Customer is a Tight so and so, Explain that you need a known good Alternator, Before you waste Lots of hours testing ecu's and wiring etc.

H.T.H. Tony.