I can see no reason to bypass the battery disconnect solenoid (Relay) save for failure of either the relay or it's control switch. I did have a control switch fail on me, and when it did that was the temp fix.. I later fixed the switch.
As for disconnecting the battery.. Some folks do that when they store the rig, Disconnecting the battery physically is the best way, in fact ONLY WAY to insure it is 100% disconnected.
As for bypassing or disconnecting the Power Guard... Not sure what that is exactly (There are a few possible candidates) but if it's a 120 volt incoming power guard system then should park power be a bit "Wild" (not sticking to the 110-120 volt spec) they tend to annoy by shutting off and requiring you manually reset.. Some folks whoud rather disconnect than put up with the hassle of resetting several times a day due to out of spec voltage
I prefer to compalin to park management when that happens.. Im paying for good power after all, it's their responsibility to deliver
If it is the converter... Well.. likely due to a failure or due to it being single stage and you may have a second converter somewhere in the rig..
If you are near S.E. michigan I can look it over, Several other members here have the skills as well and one may be close to you
