This is beyond my ability and I will be taking it in to a mechanic to look at.

I could not find the voltmeter. I might have tossed it, I don't know.

If I had an inside shop, had a little more electrical knowledge and all it might be interesting to learn this, but for right now my regular job is such that it is more reasonable to pay someone else to do it while I work.

I work on my vehicles as relaxation from my regular job, this would not be relaxing to me.