I have a 2000 24v cummins, compound turbos and all that fun stuff. I'm just curious on what everyone is reading for their ecm volts because mine seems low.. while cruising on the highway it's at 12.4, but at an idle it drops to 11.6? Is this normal?

 

Doesn't sound normal. When running, volts should read approx 14.0 -14.4. I'd check all battery connections and also get the alternator checked.