Jamie,
Please keep us informed. I'm on the same search.
I just checked the Jensen schematic and it shows 3 power connections
Pin B4 +12 volts ACC switched
Pin B5 ground
Pin B7 + 12 volts battery
I would assume B4 is +12 out for accessories you want to switch on and off with the system. B5 and B7 should be the two connected to the house batteries. I know mine won't work with the battery switch in storage mode, but I didn't think to check the clock.
There are three pins: B1, B2, and B8 that are listed as "No connection". Maybe one of them is actually connected to the chassis battery to maintain the clock?
Randy
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