So I tried that DIODE under the dash and it did nothing. It did measure a little different in diode check of 500 that was in there vs 450 of what I replaced it with. It did only work one way as designed as well. I tried a relay I had with no change but since it i easy why not. I am going to remove number 2 alternator and get it tested and see if the internal diode pack is ok. It is acting like one of the three is not working once it gets hot. I usually don't have a problem figuring out what the issue is but this one is getting old. Rebuilt this just about 2 years ago I think.