Electrical Issues on H306 2003

[ADG]

I recently purchased a 2003 H306 and I have questions about the electrical system. I can plug into shore power and the AC works great including the battery charger. When it is plugged in to shore and the AC breaker is on, I flip the 12VDC breaker and I do not get any 12VDC power for lights, etc... If I flip the AC breaker on, select one or both of the batteries and flip the 12VDC breaker, I hear something in the panel clicking for 5 seconds and get a "Ground Wire Fail" on the ProMariner Galvanic Isolator Monitor.
Although, if I disconnect from shore, the 12VDC runs well.
Am I doing something wrong? Could my shore power be incorrectly wired (why would the AC work?). I thank you for your assistance!

 

[ADG]

One more observation- if the boat is plugged into shore and AC is off and I turn on battery I get the ground wire fail alarm, but if I unplug from shore power and turn battery on - no alarm. Maybe my shore power is bad.

 

[ADG]

Good news. Problem solved. Alarms were due to bad shore power. I asked the marina to check power and they found a loose ground wire. Everything ok now!