With the engine running, once it hits high idle speed, the voltage meter on the driver console shows 16volts. The Heart Interface with show 15.5v and sometimes go into fault due to the over voltage. I take it that the alternator regulator has gone bad or there is a problem with the alternator sensing the voltage of the chassis batteries. Is there anything else I should check? From reading through the boards, it sounds like the regulator is part of the alternator and therefore the alternator needs to be rebuilt or replaced. How difficult is it to remove the alternator myself? I've done so on a couple cars, but this big diesel engine, and the complex wiring of a motorhome, is new to me as of a few months ago.
And, as a possibly unrelated question, there is a white wire connected to the negative terminal of the chassis batteries. If this is not connected, the engine will not start, it will not even turn over. I find it odd that something needs to connect directly to the negative terminal versus the grounded chassis. What is this wire? Does it have something to do with the alternator sensing?
Thanks so much. This is my first post.