There seem to be variations on how the radio is powered from experiences we've related on here..
There are 2 power leads into the radio... One intended to be continuous to maintain memory functions - and one intended to be on with accessory to power radio itself.
On some units - the continuous power comes from chassis, and the accessory power comes from coach.
On my 2014 Hurricane - appears all power comes from the coach - as no setting are retained when the coach is in STORE mode - and no issue with chassis battery drain.
On my 2000 Infinity - all radio power came from the chassis battery (that unit also had a chassis disconnect switch). The radio didn't work at all unless chassis power was on and key in accessory position.
To me, I'd rather have it all come from the coach as in my Hurricane - no issues of draining chassis battery, and radio works when camping without key. Of course have to have the coach battery in USE to have the rear/side cameras work.
Not difficult to change connections to draw power where you want it to come from...
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