I've been following this thread since it was made as it relates very closely to a problem I'm having. I'm about as confused as ever now.

I've looked for wiring diagrams and diagrams to bypass the computerized charging on my truck, and my search-fu fails

 

AeSix, I will give you the same advise I always give on wiring diagrams. For 10 cents a page you can copy great wiring diagrams at your local library. Most libraries have subscriptions to some auto manuals on line or professional books on the shelf.

 

I will get another diagram. Like I said, it confused me and I'm experienced in electronics. Far too much is not shown in the diagram.

Another test I did today was to check wire resistance and continuity. The battery voltage, with truck off was 12.2. When I started it, the voltage dropped to 11.3. I used a DVM to measure voltage from the Bat- to the Alternator RED connection and battery voltage is present (11.3 +/-). So the path is good. It's the same at the input to the VR so that path is good. The voltage dropped across the wiring is about 300mV. It's beginning to look like the problem is the output of the VR or the field windings or wiring between the VR and the Alternator on the VR output side. I'm going with the latter for now, since the VR and Alternator have been replaced, while trying to fix this problem, so they are new. But I'm sure I cnecked continuity between VR and Alt already. I guess it never hurts to check more than once.

Hopefully a new wiring diagram will clear things up.

 

A common problem on our trucks is a poor ground to the VR so be sure it is well grounded. A lot of the time you may need to run a good ground wire from the VR attaching screw to the engine.

 

Hi,

When your checking for voltage at the Battery, what RPM is the truck running at? Most Alternators will not put out maximum regulated voltage till the engine is ran between 1500 - 2000RPM. Any time we do charging system tests on customer vehicles, we have to run the engine at this RPM.

Do you also do any voltage drop tests on the wiring on the feed and ground sides?

When i get back from work tomorrow, ill take a look at one of my electrical diagnosis books for the class i took at college as i know theres some info there on Chrysler external and internal regulated alternators and there sensing circuits. The sensing circut for the truck your working on comes via the ignition switch.